feat(shell): add $.trace for analyzing shell commands without execution by robobun · Pull Request #25667 · oven-sh/bun

robobun · 2025-12-24T00:19:41Z

Summary

Adds Bun.$.trace for tracing shell commands without executing them.

const result = $.trace`cat /tmp/file.txt > output.txt`;
// { operations: [...], cwd: "...", success: true, error: null }

Test plan

bun bd test test/js/bun/shell/trace.test.ts

🤖 Generated with Claude Code

robobun · 2025-12-24T00:19:51Z

^{Updated 6:08 PM PT - Dec 27th, 2025}

❌ Your commit 7a333e53 has 3 failures in Build #33802 (All Failures):

test/integration/next-pages/test/dev-server.test.ts - 1 failing on 🍎 13 aarch64
test/regression/issue/11297/11297.test.ts - 1 failing on 🪟 2019 x64
test/js/bun/test/parallel/test-http-should-emit-close-when-connection-is-aborted.ts - timeout on 🪟 2019 x64
test/js/bun/test/parallel/test-http-should-emit-close-when-connection-is-aborted.ts - timeout on 🪟 2019 x64-baseline

🧪 To try this PR locally:

bunx bun-pr 25667

That installs a local version of the PR into your bun-25667 executable, so you can run:

bun-25667 --bun

coderabbitai · 2025-12-24T00:21:52Z

Walkthrough

Adds a Zig TraceInterpreter module and exposes a new host binding traceShellScript on BunObject, wires the binding through C++ into BunShell construction, adds a JS BunShell.trace API and types, implements brace expansion helper, and adds comprehensive trace tests.

Changes

Cohort / File(s)	Summary
Core tracing engine `src/shell/TraceInterpreter.zig`, `src/shell/shell.zig`	New TraceInterpreter module with Permission/Stream/EnvSnapshot/TracedOperation/TraceResult/TraceContext types; public `trace` and `traceShellScript` functions; `shell.zig` imports & re-exports it.
Zig BunObject export `src/bun.js/api/BunObject.zig`	Adds `pub const traceShellScript = toJSCallback(bun.shell.TraceInterpreter.traceShellScript);` and registers it in `exportAll()` as `"traceShellScript"`.
C++ bindings & header `src/bun.js/bindings/BunObject.cpp`, `src/bun.js/bindings/BunObject+exports.h`	Declares `BunObject_callback_traceShellScript`, creates `traceShellScriptFunction` and appends it into BunShell construction args to expose the host callback.
JavaScript API `src/js/builtins/shell.ts`	Adds `ShellTraceOperation` and `ShellTraceResult` interfaces, extends `createBunShellTemplateFunction` to accept `traceShellScript_`, and implements `BunShell.trace(first, ...rest)` that calls the native binding.
Brace expansion helper `src/shell/braces.zig`	Adds `pub fn expandBracesAlloc(input, allocator)` returning expanded variants as a caller-owned list.
Tests `test/js/bun/shell/trace.test.ts`	New comprehensive test suite covering permissions, redirections, streams, env handling, expansions, subshells, path resolution, interpolation, and ensuring no commands execute.

Suggested reviewers

nektro
taylordotfish
zackradisic

Pre-merge checks

❌ Failed checks (1 inconclusive)

Check name	Status	Explanation	Resolution
Description check	❓ Inconclusive	The description provides a clear summary with code example and test plan, but does not fully follow the template structure with the specified section headings.	Reorganize the description to explicitly use the template sections: 'What does this PR do?' and 'How did you verify your code works?' for better consistency.

✅ Passed checks (1 passed)

Check name	Status	Explanation
Title check	✅ Passed	The PR title accurately summarizes the main change: adding a shell trace feature ($.trace) that analyzes commands without executing them.

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

coderabbitai

Actionable comments posted: 8

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📥 Commits

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📒 Files selected for processing (7)

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h
src/bun.js/bindings/BunObject.cpp
src/js/builtins/shell.ts
src/shell/TraceInterpreter.zig
src/shell/shell.zig
test/js/bun/shell/trace.test.ts

🧰 Additional context used

📓 Path-based instructions (12)

src/**/*.{cpp,zig}

📄 CodeRabbit inference engine (.cursor/rules/building-bun.mdc)

src/**/*.{cpp,zig}: Use bun bd or bun run build:debug to build debug versions for C++ and Zig source files; creates debug build at ./build/debug/bun-debug
Run tests using bun bd test <test-file> with the debug build; never use bun test directly as it will not include your changes
Execute files using bun bd <file> <...args>; never use bun <file> directly as it will not include your changes
Enable debug logs for specific scopes using BUN_DEBUG_$(SCOPE)=1 environment variable
Code generation happens automatically as part of the build process; no manual code generation commands are required

Files:

src/bun.js/api/BunObject.zig
src/shell/shell.zig
src/bun.js/bindings/BunObject.cpp
src/shell/TraceInterpreter.zig

src/**/*.zig

📄 CodeRabbit inference engine (.cursor/rules/building-bun.mdc)

Use bun.Output.scoped(.${SCOPE}, .hidden) for creating debug logs in Zig code

Implement core functionality in Zig, typically in its own directory in src/

src/**/*.zig: Private fields in Zig are fully supported using the # prefix: struct { #foo: u32 };
Use decl literals in Zig for declaration initialization: const decl: Decl = .{ .binding = 0, .value = 0 };
Prefer @import at the bottom of the file (auto formatter will move them automatically)

Files:

src/bun.js/api/BunObject.zig
src/shell/shell.zig
src/shell/TraceInterpreter.zig

src/bun.js/api/BunObject.zig

📄 CodeRabbit inference engine (.cursor/rules/registering-bun-modules.mdc)

Implement getter functions in src/bun.js/api/BunObject.zig that return your feature, and export them in the exportAll() function

Files:

src/bun.js/api/BunObject.zig

**/*.zig

📄 CodeRabbit inference engine (.cursor/rules/zig-javascriptcore-classes.mdc)

**/*.zig: Expose generated bindings in Zig structs using pub const js = JSC.Codegen.JS<ClassName> with trait conversion methods: toJS, fromJS, and fromJSDirect
Use consistent parameter name globalObject instead of ctx in Zig constructor and method implementations
Use bun.JSError!JSValue return type for Zig methods and constructors to enable proper error handling and exception propagation
Implement resource cleanup using deinit() method that releases resources, followed by finalize() called by the GC that invokes deinit() and frees the pointer
Use JSC.markBinding(@src()) in finalize methods for debugging purposes before calling deinit()
For methods returning cached properties in Zig, declare external C++ functions using extern fn and callconv(JSC.conv) calling convention
Implement getter functions with naming pattern get<PropertyName> in Zig that accept this and globalObject parameters and return JSC.JSValue
Access JavaScript CallFrame arguments using callFrame.argument(i), check argument count with callFrame.argumentCount(), and get this with callFrame.thisValue()
For reference-counted objects, use .deref() in finalize instead of destroy() to release references to other JS objects

In Zig code, be careful with allocators and use defer for cleanup

Files:

src/bun.js/api/BunObject.zig
src/shell/shell.zig
src/shell/TraceInterpreter.zig

test/**/*.{js,ts,jsx,tsx}

📄 CodeRabbit inference engine (.cursor/rules/writing-tests.mdc)

test/**/*.{js,ts,jsx,tsx}: Write tests as JavaScript and TypeScript files using Jest-style APIs (test, describe, expect) and import from bun:test
Use test.each and data-driven tests to reduce boilerplate when testing multiple similar cases

Files:

test/js/bun/shell/trace.test.ts

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}

📄 CodeRabbit inference engine (test/CLAUDE.md)

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}: Use bun:test with files that end in *.test.{ts,js,jsx,tsx,mjs,cjs}
Do not write flaky tests. Never wait for time to pass in tests; always wait for the condition to be met instead of using an arbitrary amount of time
Never use hardcoded port numbers in tests. Always use port: 0 to get a random port
Prefer concurrent tests over sequential tests using test.concurrent or describe.concurrent when multiple tests spawn processes or write files, unless it's very difficult to make them concurrent
When spawning Bun processes in tests, use bunExe and bunEnv from harness to ensure the same build of Bun is used and debug logging is silenced
Use -e flag for single-file tests when spawning Bun processes
Use tempDir() from harness to create temporary directories with files for multi-file tests instead of creating files manually
Prefer async/await over callbacks in tests
When callbacks must be used and it's just a single callback, use Promise.withResolvers to create a promise that can be resolved or rejected from a callback
Do not set a timeout on tests. Bun already has timeouts
Use Buffer.alloc(count, fill).toString() instead of 'A'.repeat(count) to create repetitive strings in tests, as ''.repeat is very slow in debug JavaScriptCore builds
Use describe blocks for grouping related tests
Always use await using or using to ensure proper resource cleanup in tests for APIs like Bun.listen, Bun.connect, Bun.spawn, Bun.serve, etc
Always check exit codes and test error scenarios in error tests
Use describe.each() for parameterized tests
Use toMatchSnapshot() for snapshot testing
Use beforeAll(), afterEach(), beforeEach() for setup/teardown in tests
Track resources (servers, clients) in arrays for cleanup in afterEach()

Files:

test/js/bun/shell/trace.test.ts

**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

**/*.test.ts?(x): Never use bun test directly - always use bun bd test to run tests with debug build changes
For single-file tests, prefer -e flag over tempDir
For multi-file tests, prefer tempDir and Bun.spawn over single-file tests
Use normalizeBunSnapshot to normalize snapshot output of tests
Never write tests that check for 'panic', 'uncaught exception', or similar strings in test output
Use tempDir from harness to create temporary directories - do not use tmpdirSync or fs.mkdtempSync
When spawning processes in tests, expect stdout before expecting exit code for more useful error messages on test failure
Do not write flaky tests - do not use setTimeout in tests; instead await the condition to be met
Verify tests fail with USE_SYSTEM_BUN=1 bun test <file> and pass with bun bd test <file> - tests are invalid if they pass with USE_SYSTEM_BUN=1
Test files must end with .test.ts or .test.tsx
Avoid shell commands like find or grep in tests - use Bun's Glob and built-in tools instead

Files:

test/js/bun/shell/trace.test.ts

test/**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

Always use port: 0 in tests - do not hardcode ports or use custom random port number functions

Files:

test/js/bun/shell/trace.test.ts

src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js}

📄 CodeRabbit inference engine (src/js/CLAUDE.md)

src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js}: Use .$call() and .$apply() instead of .call() and .apply() to prevent user tampering with function invocation
Use string literal require() statements only; dynamic requires are not permitted
Export modules using export default { ... } syntax; modules are NOT ES modules
Use JSC intrinsics (prefixed with $) such as $Array.from(), $isCallable(), and $newArrayWithSize() for performance-critical operations
Use private globals and methods with $ prefix (e.g., $Array, map.$set()) instead of public JavaScript globals
Use $debug() for debug logging and $assert() for assertions; both are stripped in release builds
Validate function arguments using validators from internal/validators and throw $ERR_* error codes for invalid arguments
Use process.platform and process.arch for platform detection; these values are inlined and dead-code eliminated at build time

Files:

src/js/builtins/shell.ts

src/js/{builtins,node,bun,thirdparty,internal}/**/*.ts

📄 CodeRabbit inference engine (src/js/CLAUDE.md)

Builtin functions must include this parameter typing in TypeScript to enable direct method binding in C++

Files:

src/js/builtins/shell.ts

src/bun.js/bindings/BunObject+exports.h

📄 CodeRabbit inference engine (.cursor/rules/registering-bun-modules.mdc)

Add an entry to the FOR_EACH_GETTER macro in src/bun.js/bindings/BunObject+exports.h when registering new features

Files:

src/bun.js/bindings/BunObject+exports.h

src/bun.js/bindings/**/*.cpp

📄 CodeRabbit inference engine (CLAUDE.md)

src/bun.js/bindings/**/*.cpp: Create classes in three parts in C++ when there is a public constructor: Foo (JSDestructibleObject), FooPrototype (JSNonFinalObject), and FooConstructor (InternalFunction)
Define properties using HashTableValue arrays in C++ JavaScript class bindings
Add iso subspaces for C++ classes with fields in JavaScript class bindings
Cache structures in ZigGlobalObject for JavaScript class bindings

Files:

src/bun.js/bindings/BunObject.cpp

🧠 Learnings (53)

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to src/bun.js/api/BunObject.zig : Implement getter functions in `src/bun.js/api/BunObject.zig` that return your feature, and export them in the `exportAll()` function

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-11-24T18:37:47.899Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/AGENTS.md:0-0
Timestamp: 2025-11-24T18:37:47.899Z
Learning: Applies to src/bun.js/bindings/v8/**/<UNKNOWN> : <UNKNOWN>

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h
src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to src/bun.js/bindings/generated_classes_list.zig : Include new class bindings in `src/bun.js/bindings/generated_classes_list.zig` to register them with the code generator

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to src/bun.js/bindings/**/*.cpp : Cache structures in ZigGlobalObject for JavaScript class bindings

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h
src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to src/bun.js/bindings/BunObject+exports.h : Add an entry to the `FOR_EACH_GETTER` macro in `src/bun.js/bindings/BunObject+exports.h` when registering new features

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h
src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/src/symbols.dyn : Add symbol names with leading underscore and semicolons in braces to src/symbols.dyn for each new V8 API method

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h
src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/V8*.h : Add BUN_EXPORT visibility attribute to all public V8 API functions to ensure proper symbol export across platforms

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h
src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/src/symbols.txt : Add symbol names without leading underscore to src/symbols.txt for each new V8 API method

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/src/napi/napi.zig : For each new V8 C++ method, add both GCC/Clang and MSVC mangled symbol names to the V8API struct in src/napi/napi.zig using extern fn declarations

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-11-24T18:35:25.883Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/javascriptcore-class.mdc:0-0
Timestamp: 2025-11-24T18:35:25.883Z
Learning: Applies to *.zig : In Zig, declare external C++ functions and wrap them in public methods using the convention `extern fn Bun__ClassName__toJS(...)` and `pub fn toJS(...)`

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h
src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Write JS builtins for Bun's Node.js compatibility and APIs, and run `bun bd` after changes

Applied to files:

src/bun.js/api/BunObject.zig
src/js/builtins/shell.ts
src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-09-20T05:35:57.318Z

Learnt from: pfgithub
Repo: oven-sh/bun PR: 22534
File: src/bun.js/bindings/headers.h:729-731
Timestamp: 2025-09-20T05:35:57.318Z
Learning: symbols.txt in the Bun codebase is specifically for V8 API mangled symbols (without leading underscore), not for general Bun host functions declared with BUN_DECLARE_HOST_FUNCTION. Host functions are handled through different build mechanisms.

Applied to files:

src/bun.js/api/BunObject.zig

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/test/v8/v8-module/main.cpp : Create test functions in test/v8/v8-module/main.cpp that take FunctionCallbackInfo<Value> parameter, use the test V8 API, print results for comparison with Node.js, and return Undefined

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/test/v8/v8-module/main.cpp : Register new V8 API test functions in the Init method using NODE_SET_METHOD with exports object

Applied to files:

src/bun.js/api/BunObject.zig

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to **/js_*.zig : Implement proper memory management with reference counting using `ref()`/`deref()` in JavaScript bindings

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-09-02T17:14:46.924Z

Learnt from: taylordotfish
Repo: oven-sh/bun PR: 22227
File: src/safety/alloc.zig:93-95
Timestamp: 2025-09-02T17:14:46.924Z
Learning: In bun's Zig codebase, they use a custom extension of Zig that supports private field syntax with the `#` prefix (e.g., `#allocator`, `#trace`). This is not standard Zig syntax but is valid in their custom implementation. Fields prefixed with `#` are private fields that cannot be accessed from outside the defining struct.

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : Expose generated bindings in Zig structs using `pub const js = JSC.Codegen.JS<ClassName>` with trait conversion methods: `toJS`, `fromJS`, and `fromJSDirect`

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to src/**/*.zig : Implement core functionality in Zig, typically in its own directory in `src/`

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : Use `JSC.markBinding(src())` in finalize methods for debugging purposes before calling `deinit()`

Applied to files:

src/shell/shell.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-08-30T09:09:18.384Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 22231
File: src/bundler/bundle_v2.zig:48-48
Timestamp: 2025-08-30T09:09:18.384Z
Learning: In Zig, when a module exports a top-level struct, import("./Module.zig") directly returns that struct type and can be used as a type alias without needing to access a field within the module. This is a common pattern in the Bun codebase.

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-10-14T04:04:17.132Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23636
File: src/shell/interpreter.zig:672-0
Timestamp: 2025-10-14T04:04:17.132Z
Learning: In Bun's shell interpreter (src/shell/interpreter.zig), the JavaScript garbage collector's memory reporting API only allows reporting extra memory allocation once at object creation time. Therefore, `estimated_size_for_gc` is intentionally set once during initialization and not updated afterward, even though fields like `root_io`, `vm_args_utf8`, and `export_env` may be mutated later. The `estimatedSize()` method returns this cached initial value, while `memoryCost()` computes the size on-demand.

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/test/v8/v8.test.ts : Add corresponding test cases to test/v8/v8.test.ts using checkSameOutput() function to compare Node.js and Bun output

Applied to files:

test/js/bun/shell/trace.test.ts
src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/dev/sourcemap.test.ts : Organize source-map tests in sourcemap.test.ts for tests verifying source-maps are correct

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/dev/esm.test.ts : Organize ESM tests in esm.test.ts for tests about various ESM features in development mode

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:50.422Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/writing-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:50.422Z
Learning: Applies to test/**/*.{js,ts,jsx,tsx} : Write tests as JavaScript and TypeScript files using Jest-style APIs (`test`, `describe`, `expect`) and import from `bun:test`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : When spawning Bun processes in tests, use `bunExe` and `bunEnv` from `harness` to ensure the same build of Bun is used and debug logging is silenced

Applied to files:

test/js/bun/shell/trace.test.ts
src/js/builtins/shell.ts

📚 Learning: 2025-10-19T02:44:46.354Z

Learnt from: theshadow27
Repo: oven-sh/bun PR: 23798
File: packages/bun-otel/context-propagation.test.ts:1-1
Timestamp: 2025-10-19T02:44:46.354Z
Learning: In the Bun repository, standalone packages under packages/ (e.g., bun-vscode, bun-inspector-protocol, bun-plugin-yaml, bun-plugin-svelte, bun-debug-adapter-protocol, bun-otel) co-locate their tests with package source code using *.test.ts files. This follows standard npm/monorepo patterns. The test/ directory hierarchy (test/js/bun/, test/cli/, test/js/node/) is reserved for testing Bun's core runtime APIs and built-in functionality, not standalone packages.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Never use `bun test` directly - always use `bun bd test` to run tests with debug build changes

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Avoid shell commands like `find` or `grep` in tests - use Bun's Glob and built-in tools instead

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/dev/bundle.test.ts : Organize bundle tests in bundle.test.ts for tests concerning bundling bugs that only occur in DevServer

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Use `normalizeBunSnapshot` to normalize snapshot output of tests

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:50.422Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/writing-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:50.422Z
Learning: Applies to test/cli/**/*.{js,ts,jsx,tsx} : When testing Bun as a CLI, use the `spawn` API from `bun` with the `bunExe()` and `bunEnv` from `harness` to execute Bun commands and validate exit codes, stdout, and stderr

Applied to files:

test/js/bun/shell/trace.test.ts
src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Add tests for new Bun runtime functionality

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-26T01:32:04.844Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 24082
File: test/cli/test/coverage.test.ts:60-112
Timestamp: 2025-10-26T01:32:04.844Z
Learning: In the Bun repository test files (test/cli/test/*.test.ts), when spawning Bun CLI commands with Bun.spawnSync for testing, prefer using stdio: ["inherit", "inherit", "inherit"] to inherit stdio streams rather than piping them.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Verify tests fail with `USE_SYSTEM_BUN=1 bun test <file>` and pass with `bun bd test <file>` - tests are invalid if they pass with USE_SYSTEM_BUN=1

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `-e` flag for single-file tests when spawning Bun processes

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/js/node/test/{parallel,sequential}/*.js : For test/js/node/test/{parallel,sequential}/*.js files without a .test extension, use `bun bd <file>` instead of `bun bd test <file>` since these expect exit code 0 and don't use bun's test runner

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `$debug()` for debug logging and `$assert()` for assertions; both are stripped in release builds

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-10-19T02:52:37.412Z

Learnt from: theshadow27
Repo: oven-sh/bun PR: 23798
File: packages/bun-otel/tsconfig.json:1-15
Timestamp: 2025-10-19T02:52:37.412Z
Learning: In the Bun repository, packages under packages/ (e.g., bun-otel) can follow a TypeScript-first pattern where package.json exports point directly to .ts files (not compiled .js files). Bun natively runs TypeScript, so consumers import .ts sources directly and receive full type information without needing compiled .d.ts declaration files. For such packages, adding "declaration": true or "outDir" in tsconfig.json is unnecessary and would break the export structure.
<!-- [remove_learning]
ceedde95-980e-4898-a2c6-40ff73913664

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-14T16:07:01.064Z

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 24719
File: docs/bundler/executables.mdx:527-560
Timestamp: 2025-11-14T16:07:01.064Z
Learning: In the Bun repository, certain bundler features like compile with code splitting (--compile --splitting) are CLI-only and not supported in the Bun.build() JavaScript API. Tests for CLI-only features use backend: "cli" flag (e.g., test/bundler/bundler_compile_splitting.test.ts). The CompileBuildConfig interface correctly restricts these with splitting?: never;. When documenting CLI-only bundler features, add a note clarifying they're not available via the programmatic API.

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `process.platform` and `process.arch` for platform detection; these values are inlined and dead-code eliminated at build time

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.ts : Builtin functions must include `this` parameter typing in TypeScript to enable direct method binding in C++

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use private globals and methods with `$` prefix (e.g., `$Array`, `map.$set()`) instead of public JavaScript globals

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-10-14T04:04:47.894Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23636
File: src/shell/ParsedShellScript.zig:15-0
Timestamp: 2025-10-14T04:04:47.894Z
Learning: In src/shell/ParsedShellScript.zig, the JavaScript garbage collector's memory reporting API only allows reporting extra memory allocation once at object creation time. Therefore, `estimated_size_for_gc` is intentionally set once during initialization (via `#computeEstimatedSizeForGC()`) and not updated afterward, even though fields like `args`, `export_env`, and `cwd` may be mutated by methods like `setCwd()`, `setEnv()`, and `take()`. The `estimatedSize()` method returns this cached initial value, while `memoryCost()` computes the size on-demand.

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-12-23T06:50:31.577Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 25429
File: src/bun.js/bindings/helpers.h:422-422
Timestamp: 2025-12-23T06:50:31.577Z
Learning: In Bun's C++ bindings, when returning an empty JSC::Identifier and a VM is accessible, prefer using vm.propertyNames->emptyIdentifier over constructing with JSC::Identifier(JSC::Identifier::EmptyIdentifierFlag::EmptyIdentifier). The cached identifier from the VM's property names table is more efficient and consistent with WebKit upgrade patterns. Apply this guidance to src/bun.js/bindings/helpers.h and similar header files in the same bindings directory (i.e., any file that constructs an EmptyIdentifier).

Applied to files:

src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to src/bun.js/bindings/**/*.cpp : Create classes in three parts in C++ when there is a public constructor: Foo (JSDestructibleObject), FooPrototype (JSNonFinalObject), and FooConstructor (InternalFunction)

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to src/bun.js/bindings/**/*.cpp : Add iso subspaces for C++ classes with fields in JavaScript class bindings

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/V8*.h : Create V8 class headers with .h extension following the pattern V8ClassName.h that include pragma once, v8.h, V8Local.h, V8Isolate.h, and declare classes extending from Data with BUN_EXPORT static methods

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/V8*.cpp : Create V8 class implementations with .cpp extension following the pattern V8ClassName.cpp that include the header, v8_compatibility_assertions.h, use ASSERT_V8_TYPE_LAYOUT_MATCHES macro, and implement methods using isolate->currentHandleScope()->createLocal<T>() for handle creation

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:35:25.883Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/javascriptcore-class.mdc:0-0
Timestamp: 2025-11-24T18:35:25.883Z
Learning: Applies to *.cpp : To create JavaScript objects from Zig, implement C++ functions following the `Bun__ClassName__toJS(Zig::GlobalObject*, NativeType*)` convention that construct and return the JavaScript object as an encoded JSValue

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to **/js_*.zig : Use `bun.JSError!JSValue` for proper error propagation in JavaScript bindings

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:35:25.883Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/javascriptcore-class.mdc:0-0
Timestamp: 2025-11-24T18:35:25.883Z
Learning: Applies to *.cpp : Expose C++ class constructors to Zig using `extern "C"` functions following the pattern `Bun__JSClassName(Zig::GlobalObject*)` that return the encoded JSValue constructor

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/V8*.cpp : Use localToJSValue() to convert V8 handles to JSC values and perform JSC operations within V8 method implementations

Applied to files:

src/bun.js/bindings/BunObject.cpp

🧬 Code graph analysis (1)

test/js/bun/shell/trace.test.ts (1)

scripts/utils.mjs (1)

$ (143-161)

🪛 GitHub Check: Lint JavaScript

src/js/builtins/shell.ts

[failure] 5-5: eslint(no-unused-vars)
Interface 'ShellTraceFlags' is declared but never used.

🔇 Additional comments (10)

src/bun.js/bindings/BunObject.cpp (1)

352-365: traceShellScript binding is correctly injected into BunShell construction

traceShellScriptFunction is created in the same pattern as the other shell helpers and appended to the argument list passed into shellCreateBunShellTemplateFunctionCodeGenerator, so wiring of BunObject_callback_traceShellScript into BunShell looks consistent with existing conventions.

src/bun.js/bindings/BunObject+exports.h (1)

38-80: Callback registration for traceShellScript is consistent with existing BunObject bindings

Adding macro(traceShellScript) to FOR_EACH_CALLBACK correctly generates the BunObject_callback_traceShellScript declaration and keeps the callback list in sync with the BunObject C++ and Zig bindings.

src/bun.js/api/BunObject.zig (1)

19-19: LGTM!

The traceShellScript callback is properly registered following the established pattern for shell-related callbacks, consistent with createParsedShellScript and createShellInterpreter. The export naming convention is correctly applied.

Also applies to: 158-158

src/js/builtins/shell.ts (1)

399-413: LGTM!

The trace function correctly follows the same pattern as the main BunShell tagged template function, including proper validation of tagged template usage and consistent cwd/env handling. The implementation appropriately delegates to the Zig-based traceShellScript.
test/js/bun/shell/trace.test.ts (2)
1-306: Test suite is comprehensive and well-structured.

The tests thoroughly cover:

Basic trace result structure

Builtin commands (cat, rm, mkdir, touch, cp, mv, cd, ls, echo, export)

File permissions (READ, CREATE, DELETE, MKDIR, CHDIR, ENV)

Redirections with stream markers (stdin, stdout, stderr)

Pipelines and logical operators

Subshell cwd isolation

Template interpolation

Non-execution verification

Good use of describe blocks and clear test naming. As per coding guidelines, tests use bun:test imports correctly.

32-39: Missing stream property in ShellTraceOperation interface.

The tests at lines 149-152, 159-162, and 169-171 check for op.stream, but the ShellTraceOperation interface in shell.ts doesn't include this field. The Zig code (TracedOperation.toJS) correctly outputs the stream property.

Update the interface in src/js/builtins/shell.ts:
🔎 Proposed fix for shell.ts
 interface ShellTraceOperation {
   /** Permission flags (octal integer, can be combined with |) */
   flags: number;
   path: string | null;
   command: string | null;
   cwd: string;
   envVar: string | null;
+  stream: "stdin" | "stdout" | "stderr" | null;
 }
⛔ Skipped due to learnings
Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 24082
File: test/cli/test/coverage.test.ts:60-112
Timestamp: 2025-10-26T01:32:04.844Z
Learning: In the Bun repository test files (test/cli/test/*.test.ts), when spawning Bun CLI commands with Bun.spawnSync for testing, prefer using stdio: ["inherit", "inherit", "inherit"] to inherit stdio streams rather than piping them.
Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : When spawning processes in tests, expect stdout before expecting exit code for more useful error messages on test failure
Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Avoid shell commands like `find` or `grep` in tests - use Bun's Glob and built-in tools instead
Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For single-file tests, prefer `-e` flag over `tempDir`
Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For multi-file tests, prefer `tempDir` and `Bun.spawn` over single-file tests
src/shell/TraceInterpreter.zig (4)

10-35: LGTM!

Permission constants correctly mirror standard Unix open(2) flags with appropriate octal values. Extended operation flags use higher bits to avoid conflicts with standard flags. The convenience combinations are well-defined for common use cases.

69-74: LGTM!

Memory management in TracedOperation.deinit properly frees all owned strings conditionally. The ownership model is clear - each operation owns its path, command, cwd, and env_var strings.

345-355: LGTM!

Subshell handling correctly saves and restores the parent's cwd, ensuring directory changes inside subshells don't leak to outer scope. This matches the test expectations at lines 280-295 in trace.test.ts.

1-7: Good module documentation.

The header comment clearly explains the purpose of the trace interpreter - simulating shell execution without running commands to collect permission and file access information. This is helpful for understanding the module's intent.

coderabbitai · 2025-12-24T00:27:24Z

+  test("external command resolves path when available", () => {
+    const result = $.trace`/bin/ls /tmp`;
+    expect(result.success).toBe(true);
+
+    const execOps = result.operations.filter(op => op.flags === EXECUTE);
+    expect(execOps.length).toBeGreaterThan(0);
+    // Command name should be captured
+    expect(execOps[0].command).toBe("/bin/ls");
+  });


⚠️ Potential issue | 🟡 Minor

🧩 Analysis chain

🏁 Script executed:

# First, check if the test file exists and read the relevant section cat -n test/js/bun/shell/trace.test.ts | sed -n '240,265p'

Repository: oven-sh/bun

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# Check what the trace API does - look for documentation or implementation rg -A 10 -B 2 "\.trace\`" test/js/bun/shell/trace.test.ts | head -50

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Repository: oven-sh/bun

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Length of output: 887

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# Check if there are platform guards in other shell test files find test/js/bun/shell -name "*.test.ts" -exec grep -l "process.platform\|skipIf\|Windows" {} \;

Repository: oven-sh/bun

Length of output: 317

🏁 Script executed:

# Check the git history to see if /bin/ls was always used or if there were platform considerations git log --oneline test/js/bun/shell/trace.test.ts | head -5

Repository: oven-sh/bun

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# Search for other uses of /bin/ls or hardcoded paths in shell tests rg "/bin/ls|/usr/bin" test/js/bun/shell/

Repository: oven-sh/bun

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# Check if there's any documentation about trace being Unix-only rg -i "trace.*unix|unix.*trace|platform" test/js/bun/shell/trace.test.ts

Repository: oven-sh/bun

Length of output: 37

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# Check if any shell tests have platform guards grep -r "process.platform\|skipIf\|Windows" test/js/bun/shell/ --include="*.test.ts" | head -20

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# Look at one of the other shell test files to see how they handle platform concerns head -50 test/js/bun/shell/bunshell.test.ts

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Length of output: 1846

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# Check if the trace feature is documented as Unix-only anywhere in the codebase rg -i "trace" test/js/bun/shell/trace.test.ts | grep -i "unix\|windows\|platform" | head -10

Repository: oven-sh/bun

Length of output: 37

Add platform guard to test using Unix-specific paths.

The $.trace API doesn't actually execute commands (test 243-248 confirms this), so /bin/ls non-existence won't cause test failure. However, this test uses Unix-specific paths (/bin/ls, /tmp) with no platform guard, while other shell tests in this directory consistently use test.skipIf(isWindows) or similar guards. Either skip this test on Windows using test.skipIf(isWindows) (from harness) or use a more portable approach.

🤖 Prompt for AI Agents

test/js/bun/shell/trace.test.ts around lines 250 to 258: the test uses Unix-specific paths (/bin/ls, /tmp) without a Windows guard; update the test to skip on Windows by wrapping it with the harness helper (e.g., test.skipIf(isWindows)(...) or annotate the test with test.skipIf(isWindows)) or replace the hardcoded paths with platform-neutral equivalents obtained via path APIs so the test only runs where those paths exist.

Adds `Bun.$.trace` for tracing shell commands without executing them. Usage: ```js const result = $.trace`cat /tmp/file.txt > output.txt`; // { operations: [...], cwd: "...", success: true, error: null } ``` Features: - Traces file operations with Unix permission flags - Expands brace patterns ({a,b}.txt) and tilde (~) - Handles pipelines, &&, ||, and subshells - Subshell cwd changes are properly isolated - Glob patterns kept literal (can't expand without filesystem) 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

coderabbitai

Actionable comments posted: 1

♻️ Duplicate comments (7)

src/shell/shell.zig (1)
3-6: Consider making trace_interpret internal-only to avoid duplicate public exports.

Both trace_interpret and TraceInterpreter are currently exported as public aliases to the same module. To avoid exposing two public names for the same functionality, consider making the helper internal:
const trace_interpret = @import("./TraceInterpreter.zig");
pub const TraceInterpreter = trace_interpret;
This way only the intended TraceInterpreter name is part of the public API.

Note: This issue was previously flagged in an earlier review.
test/js/bun/shell/trace.test.ts (1)
250-258: Add platform guard for test using Unix-specific paths.

This test uses /bin/ls which doesn't exist on Windows. While $.trace doesn't execute commands (test at lines 243-248 confirms this), other shell tests in this directory consistently use test.skipIf(isWindows) for Unix-specific paths. For consistency and to avoid potential assertion failures on Windows:
🔎 Suggested fix
+import { isWindows } from "harness";
+
 // ... at the test
-  test("external command resolves path when available", () => {
+  test.skipIf(isWindows)("external command resolves path when available", () => {
     const result = $.trace`/bin/ls /tmp`;
src/js/builtins/shell.ts (1)
5-30: Remove unused ShellTraceFlags interface or use it as a type annotation.

The interface is flagged by ESLint as unused. Since ShellTraceOperation.flags is typed as number, this interface serves only as documentation. Either:

Remove it (the constants are documented in the Zig code and test file)

Use it somewhere: flags: ShellTraceFlags[keyof ShellTraceFlags] or add an eslint-disable comment
🔎 Option to suppress lint
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
 interface ShellTraceFlags {
src/shell/TraceInterpreter.zig (4)
230-255: Potential double-free: export_env ownership is unclear.

When export_env is non-null, it's assigned directly to ctx.export_env (line 243). This creates a shallow copy of the EnvMap struct that shares the underlying hash table data with the caller's map. When TraceContext.deinit() calls this.export_env.deinit() (line 254), it frees memory that's also owned by parsed_shell_script.export_env.
🔎 Proposed fix: Don't deinit if we don't own it
 pub const TraceContext = struct {
     // ... fields ...
+    owns_export_env: bool,
     
     pub fn init(
         // ... params ...
     ) TraceContext {
         var ctx = TraceContext{
             // ... other fields ...
-            .export_env = if (export_env) |e| e else EnvMap.init(allocator),
+            .export_env = export_env orelse EnvMap.init(allocator),
+            .owns_export_env = export_env == null,
             // ...
         };
         // ...
     }
     
     pub fn deinit(this: *TraceContext) void {
         this.cwd.deinit();
         this.shell_env.deinit();
-        this.export_env.deinit();
+        if (this.owns_export_env) {
+            this.export_env.deinit();
+        }
     }
298-308: Path normalization issue in changeCwd.

For relative paths, the code appends '/' + new_cwd which can result in double slashes if cwd already ends with /, and doesn't resolve .. or . components. While this is for tracing (not execution), tests at lines 292-294 in trace.test.ts check cwd values directly.
🔎 Consider using path join
 pub fn changeCwd(this: *TraceContext, new_cwd: []const u8) void {
     if (ResolvePath.Platform.auto.isAbsolute(new_cwd)) {
         this.cwd.clearRetainingCapacity();
         bun.handleOom(this.cwd.appendSlice(new_cwd));
     } else {
-        bun.handleOom(this.cwd.append('/'));
-        bun.handleOom(this.cwd.appendSlice(new_cwd));
+        const parts: []const []const u8 = &.{ this.cwdSlice(), new_cwd };
+        const joined = ResolvePath.joinZ(parts, .auto);
+        this.cwd.clearRetainingCapacity();
+        bun.handleOom(this.cwd.appendSlice(joined[0..joined.len]));
     }
 }
873-908: expandDoubleQuoted function is dead code.

This function is defined but never called anywhere in the file. The expandSimple function handles all SimpleAtom variants directly, and there's no .DoubleQuoted variant in the AST that would invoke this function.
🔎 Remove dead code
-fn expandDoubleQuoted(ctx: *TraceContext, text: []const u8, out: *std.array_list.Managed(u8)) void {
-    var i: usize = 0;
-    while (i < text.len) {
-        // ... entire function body ...
-    }
-}
570-593: mv and cp only trace the first two file arguments.

The implementation handles mv src dst but not multi-file forms like mv file1 file2 dir/. For a permission system, $.trace\mv a b c dir/`` would under-report operations.

Consider iterating all source files and detecting directory destinations:
🔎 Consider handling multiple sources
 .mv => {
     var file_args = extractFileArgs(ctx, cmd);
     defer freeFileArgs(ctx, &file_args);

-    if (file_args.items.len >= 1) {
-        ctx.addOperation(Permission.READ | Permission.DELETE, file_args.items[0], null, null);
-    }
-    if (file_args.items.len >= 2) {
-        ctx.addOperation(Permission.CREATE, file_args.items[1], null, null);
+    if (file_args.items.len >= 2) {
+        // Last arg is destination
+        const dest = file_args.items[file_args.items.len - 1];
+        // All others are sources
+        for (file_args.items[0 .. file_args.items.len - 1]) |src| {
+            ctx.addOperation(Permission.READ | Permission.DELETE, src, null, null);
+        }
+        ctx.addOperation(Permission.CREATE, dest, null, null);
     }
 },

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📒 Files selected for processing (7)

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h
src/bun.js/bindings/BunObject.cpp
src/js/builtins/shell.ts
src/shell/TraceInterpreter.zig
src/shell/shell.zig
test/js/bun/shell/trace.test.ts

🧰 Additional context used

📓 Path-based instructions (12)

test/**/*.{js,ts,jsx,tsx}

📄 CodeRabbit inference engine (.cursor/rules/writing-tests.mdc)

test/**/*.{js,ts,jsx,tsx}: Write tests as JavaScript and TypeScript files using Jest-style APIs (test, describe, expect) and import from bun:test
Use test.each and data-driven tests to reduce boilerplate when testing multiple similar cases

Files:

test/js/bun/shell/trace.test.ts

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}

📄 CodeRabbit inference engine (test/CLAUDE.md)

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}: Use bun:test with files that end in *.test.{ts,js,jsx,tsx,mjs,cjs}
Do not write flaky tests. Never wait for time to pass in tests; always wait for the condition to be met instead of using an arbitrary amount of time
Never use hardcoded port numbers in tests. Always use port: 0 to get a random port
Prefer concurrent tests over sequential tests using test.concurrent or describe.concurrent when multiple tests spawn processes or write files, unless it's very difficult to make them concurrent
When spawning Bun processes in tests, use bunExe and bunEnv from harness to ensure the same build of Bun is used and debug logging is silenced
Use -e flag for single-file tests when spawning Bun processes
Use tempDir() from harness to create temporary directories with files for multi-file tests instead of creating files manually
Prefer async/await over callbacks in tests
When callbacks must be used and it's just a single callback, use Promise.withResolvers to create a promise that can be resolved or rejected from a callback
Do not set a timeout on tests. Bun already has timeouts
Use Buffer.alloc(count, fill).toString() instead of 'A'.repeat(count) to create repetitive strings in tests, as ''.repeat is very slow in debug JavaScriptCore builds
Use describe blocks for grouping related tests
Always use await using or using to ensure proper resource cleanup in tests for APIs like Bun.listen, Bun.connect, Bun.spawn, Bun.serve, etc
Always check exit codes and test error scenarios in error tests
Use describe.each() for parameterized tests
Use toMatchSnapshot() for snapshot testing
Use beforeAll(), afterEach(), beforeEach() for setup/teardown in tests
Track resources (servers, clients) in arrays for cleanup in afterEach()

Files:

test/js/bun/shell/trace.test.ts

**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

**/*.test.ts?(x): Never use bun test directly - always use bun bd test to run tests with debug build changes
For single-file tests, prefer -e flag over tempDir
For multi-file tests, prefer tempDir and Bun.spawn over single-file tests
Use normalizeBunSnapshot to normalize snapshot output of tests
Never write tests that check for 'panic', 'uncaught exception', or similar strings in test output
Use tempDir from harness to create temporary directories - do not use tmpdirSync or fs.mkdtempSync
When spawning processes in tests, expect stdout before expecting exit code for more useful error messages on test failure
Do not write flaky tests - do not use setTimeout in tests; instead await the condition to be met
Verify tests fail with USE_SYSTEM_BUN=1 bun test <file> and pass with bun bd test <file> - tests are invalid if they pass with USE_SYSTEM_BUN=1
Test files must end with .test.ts or .test.tsx
Avoid shell commands like find or grep in tests - use Bun's Glob and built-in tools instead

Files:

test/js/bun/shell/trace.test.ts

test/**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

Always use port: 0 in tests - do not hardcode ports or use custom random port number functions

Files:

test/js/bun/shell/trace.test.ts

src/**/*.{cpp,zig}

📄 CodeRabbit inference engine (.cursor/rules/building-bun.mdc)

src/**/*.{cpp,zig}: Use bun bd or bun run build:debug to build debug versions for C++ and Zig source files; creates debug build at ./build/debug/bun-debug
Run tests using bun bd test <test-file> with the debug build; never use bun test directly as it will not include your changes
Execute files using bun bd <file> <...args>; never use bun <file> directly as it will not include your changes
Enable debug logs for specific scopes using BUN_DEBUG_$(SCOPE)=1 environment variable
Code generation happens automatically as part of the build process; no manual code generation commands are required

Files:

src/bun.js/bindings/BunObject.cpp
src/bun.js/api/BunObject.zig
src/shell/shell.zig
src/shell/TraceInterpreter.zig

src/bun.js/bindings/**/*.cpp

📄 CodeRabbit inference engine (CLAUDE.md)

src/bun.js/bindings/**/*.cpp: Create classes in three parts in C++ when there is a public constructor: Foo (JSDestructibleObject), FooPrototype (JSNonFinalObject), and FooConstructor (InternalFunction)
Define properties using HashTableValue arrays in C++ JavaScript class bindings
Add iso subspaces for C++ classes with fields in JavaScript class bindings
Cache structures in ZigGlobalObject for JavaScript class bindings

Files:

src/bun.js/bindings/BunObject.cpp

src/**/*.zig

📄 CodeRabbit inference engine (.cursor/rules/building-bun.mdc)

Use bun.Output.scoped(.${SCOPE}, .hidden) for creating debug logs in Zig code

Implement core functionality in Zig, typically in its own directory in src/

src/**/*.zig: Private fields in Zig are fully supported using the # prefix: struct { #foo: u32 };
Use decl literals in Zig for declaration initialization: const decl: Decl = .{ .binding = 0, .value = 0 };
Prefer @import at the bottom of the file (auto formatter will move them automatically)

Files:

src/bun.js/api/BunObject.zig
src/shell/shell.zig
src/shell/TraceInterpreter.zig

src/bun.js/api/BunObject.zig

📄 CodeRabbit inference engine (.cursor/rules/registering-bun-modules.mdc)

Implement getter functions in src/bun.js/api/BunObject.zig that return your feature, and export them in the exportAll() function

Files:

src/bun.js/api/BunObject.zig

**/*.zig

📄 CodeRabbit inference engine (.cursor/rules/zig-javascriptcore-classes.mdc)

**/*.zig: Expose generated bindings in Zig structs using pub const js = JSC.Codegen.JS<ClassName> with trait conversion methods: toJS, fromJS, and fromJSDirect
Use consistent parameter name globalObject instead of ctx in Zig constructor and method implementations
Use bun.JSError!JSValue return type for Zig methods and constructors to enable proper error handling and exception propagation
Implement resource cleanup using deinit() method that releases resources, followed by finalize() called by the GC that invokes deinit() and frees the pointer
Use JSC.markBinding(@src()) in finalize methods for debugging purposes before calling deinit()
For methods returning cached properties in Zig, declare external C++ functions using extern fn and callconv(JSC.conv) calling convention
Implement getter functions with naming pattern get<PropertyName> in Zig that accept this and globalObject parameters and return JSC.JSValue
Access JavaScript CallFrame arguments using callFrame.argument(i), check argument count with callFrame.argumentCount(), and get this with callFrame.thisValue()
For reference-counted objects, use .deref() in finalize instead of destroy() to release references to other JS objects

In Zig code, be careful with allocators and use defer for cleanup

Files:

src/bun.js/api/BunObject.zig
src/shell/shell.zig
src/shell/TraceInterpreter.zig

src/bun.js/bindings/BunObject+exports.h

📄 CodeRabbit inference engine (.cursor/rules/registering-bun-modules.mdc)

Add an entry to the FOR_EACH_GETTER macro in src/bun.js/bindings/BunObject+exports.h when registering new features

Files:

src/bun.js/bindings/BunObject+exports.h

src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js}

📄 CodeRabbit inference engine (src/js/CLAUDE.md)

src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js}: Use .$call() and .$apply() instead of .call() and .apply() to prevent user tampering with function invocation
Use string literal require() statements only; dynamic requires are not permitted
Export modules using export default { ... } syntax; modules are NOT ES modules
Use JSC intrinsics (prefixed with $) such as $Array.from(), $isCallable(), and $newArrayWithSize() for performance-critical operations
Use private globals and methods with $ prefix (e.g., $Array, map.$set()) instead of public JavaScript globals
Use $debug() for debug logging and $assert() for assertions; both are stripped in release builds
Validate function arguments using validators from internal/validators and throw $ERR_* error codes for invalid arguments
Use process.platform and process.arch for platform detection; these values are inlined and dead-code eliminated at build time

Files:

src/js/builtins/shell.ts

src/js/{builtins,node,bun,thirdparty,internal}/**/*.ts

📄 CodeRabbit inference engine (src/js/CLAUDE.md)

Builtin functions must include this parameter typing in TypeScript to enable direct method binding in C++

Files:

src/js/builtins/shell.ts

🧠 Learnings (55)

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/test/v8/v8.test.ts : Add corresponding test cases to test/v8/v8.test.ts using checkSameOutput() function to compare Node.js and Bun output

Applied to files:

test/js/bun/shell/trace.test.ts
src/bun.js/bindings/BunObject.cpp
src/bun.js/api/BunObject.zig
src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : When spawning Bun processes in tests, use `bunExe` and `bunEnv` from `harness` to ensure the same build of Bun is used and debug logging is silenced

Applied to files:

test/js/bun/shell/trace.test.ts
src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:35:50.422Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/writing-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:50.422Z
Learning: Applies to test/**/*.{js,ts,jsx,tsx} : Write tests as JavaScript and TypeScript files using Jest-style APIs (`test`, `describe`, `expect`) and import from `bun:test`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/dev/esm.test.ts : Organize ESM tests in esm.test.ts for tests about various ESM features in development mode

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-19T02:44:46.354Z

Learnt from: theshadow27
Repo: oven-sh/bun PR: 23798
File: packages/bun-otel/context-propagation.test.ts:1-1
Timestamp: 2025-10-19T02:44:46.354Z
Learning: In the Bun repository, standalone packages under packages/ (e.g., bun-vscode, bun-inspector-protocol, bun-plugin-yaml, bun-plugin-svelte, bun-debug-adapter-protocol, bun-otel) co-locate their tests with package source code using *.test.ts files. This follows standard npm/monorepo patterns. The test/ directory hierarchy (test/js/bun/, test/cli/, test/js/node/) is reserved for testing Bun's core runtime APIs and built-in functionality, not standalone packages.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Never use `bun test` directly - always use `bun bd test` to run tests with debug build changes

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Verify tests fail with `USE_SYSTEM_BUN=1 bun test <file>` and pass with `bun bd test <file>` - tests are invalid if they pass with USE_SYSTEM_BUN=1

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/dev/sourcemap.test.ts : Organize source-map tests in sourcemap.test.ts for tests verifying source-maps are correct

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Avoid shell commands like `find` or `grep` in tests - use Bun's Glob and built-in tools instead

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Add tests for new Bun runtime functionality

Applied to files:

test/js/bun/shell/trace.test.ts
src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `process.platform` and `process.arch` for platform detection; these values are inlined and dead-code eliminated at build time

Applied to files:

test/js/bun/shell/trace.test.ts
src/js/builtins/shell.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For multi-file tests, prefer `tempDir` and `Bun.spawn` over single-file tests

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/js/node/test/{parallel,sequential}/*.js : For test/js/node/test/{parallel,sequential}/*.js files without a .test extension, use `bun bd <file>` instead of `bun bd test <file>` since these expect exit code 0 and don't use bun's test runner

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For single-file tests, prefer `-e` flag over `tempDir`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `-e` flag for single-file tests when spawning Bun processes

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-26T01:32:04.844Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 24082
File: test/cli/test/coverage.test.ts:60-112
Timestamp: 2025-10-26T01:32:04.844Z
Learning: In the Bun repository test files (test/cli/test/*.test.ts), when spawning Bun CLI commands with Bun.spawnSync for testing, prefer using stdio: ["inherit", "inherit", "inherit"] to inherit stdio streams rather than piping them.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:50.422Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/writing-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:50.422Z
Learning: Applies to test/cli/**/*.{js,ts,jsx,tsx} : When testing Bun as a CLI, use the `spawn` API from `bun` with the `bunExe()` and `bunEnv` from `harness` to execute Bun commands and validate exit codes, stdout, and stderr

Applied to files:

test/js/bun/shell/trace.test.ts
src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `bun:test` with files that end in `*.test.{ts,js,jsx,tsx,mjs,cjs}`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/V8*.h : Add BUN_EXPORT visibility attribute to all public V8 API functions to ensure proper symbol export across platforms

Applied to files:

src/bun.js/bindings/BunObject.cpp
src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-11-24T18:37:47.899Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/AGENTS.md:0-0
Timestamp: 2025-11-24T18:37:47.899Z
Learning: Applies to src/bun.js/bindings/v8/**/<UNKNOWN> : <UNKNOWN>

Applied to files:

src/bun.js/bindings/BunObject.cpp
src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to src/bun.js/bindings/**/*.cpp : Create classes in three parts in C++ when there is a public constructor: Foo (JSDestructibleObject), FooPrototype (JSNonFinalObject), and FooConstructor (InternalFunction)

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/src/symbols.dyn : Add symbol names with leading underscore and semicolons in braces to src/symbols.dyn for each new V8 API method

Applied to files:

src/bun.js/bindings/BunObject.cpp
src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to src/bun.js/bindings/BunObject+exports.h : Add an entry to the `FOR_EACH_GETTER` macro in `src/bun.js/bindings/BunObject+exports.h` when registering new features

Applied to files:

src/bun.js/bindings/BunObject.cpp
src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to src/bun.js/bindings/**/*.cpp : Add iso subspaces for C++ classes with fields in JavaScript class bindings

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/src/symbols.txt : Add symbol names without leading underscore to src/symbols.txt for each new V8 API method

Applied to files:

src/bun.js/bindings/BunObject.cpp
src/bun.js/api/BunObject.zig

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Write JS builtins for Bun's Node.js compatibility and APIs, and run `bun bd` after changes

Applied to files:

src/bun.js/bindings/BunObject.cpp
src/bun.js/api/BunObject.zig
src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:35:25.883Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/javascriptcore-class.mdc:0-0
Timestamp: 2025-11-24T18:35:25.883Z
Learning: Applies to *.cpp : To create JavaScript objects from Zig, implement C++ functions following the `Bun__ClassName__toJS(Zig::GlobalObject*, NativeType*)` convention that construct and return the JavaScript object as an encoded JSValue

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to src/bun.js/bindings/**/*.cpp : Cache structures in ZigGlobalObject for JavaScript class bindings

Applied to files:

src/bun.js/bindings/BunObject.cpp
src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/test/v8/v8-module/main.cpp : Create test functions in test/v8/v8-module/main.cpp that take FunctionCallbackInfo<Value> parameter, use the test V8 API, print results for comparison with Node.js, and return Undefined

Applied to files:

src/bun.js/bindings/BunObject.cpp
src/bun.js/api/BunObject.zig

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to **/js_*.zig : Use `bun.JSError!JSValue` for proper error propagation in JavaScript bindings

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:35:25.883Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/javascriptcore-class.mdc:0-0
Timestamp: 2025-11-24T18:35:25.883Z
Learning: Applies to *.cpp : Expose C++ class constructors to Zig using `extern "C"` functions following the pattern `Bun__JSClassName(Zig::GlobalObject*)` that return the encoded JSValue constructor

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/V8*.cpp : Use localToJSValue() to convert V8 handles to JSC values and perform JSC operations within V8 method implementations

Applied to files:

src/bun.js/bindings/BunObject.cpp

📚 Learning: 2025-11-24T18:35:25.883Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/javascriptcore-class.mdc:0-0
Timestamp: 2025-11-24T18:35:25.883Z
Learning: Applies to *.zig : In Zig, declare external C++ functions and wrap them in public methods using the convention `extern fn Bun__ClassName__toJS(...)` and `pub fn toJS(...)`

Applied to files:

src/bun.js/bindings/BunObject.cpp
src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to src/bun.js/api/BunObject.zig : Implement getter functions in `src/bun.js/api/BunObject.zig` that return your feature, and export them in the `exportAll()` function

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to src/bun.js/bindings/generated_classes_list.zig : Include new class bindings in `src/bun.js/bindings/generated_classes_list.zig` to register them with the code generator

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : Expose generated bindings in Zig structs using `pub const js = JSC.Codegen.JS<ClassName>` with trait conversion methods: `toJS`, `fromJS`, and `fromJSDirect`

Applied to files:

src/bun.js/api/BunObject.zig
src/bun.js/bindings/BunObject+exports.h
src/shell/shell.zig

📚 Learning: 2025-09-20T05:35:57.318Z

Learnt from: pfgithub
Repo: oven-sh/bun PR: 22534
File: src/bun.js/bindings/headers.h:729-731
Timestamp: 2025-09-20T05:35:57.318Z
Learning: symbols.txt in the Bun codebase is specifically for V8 API mangled symbols (without leading underscore), not for general Bun host functions declared with BUN_DECLARE_HOST_FUNCTION. Host functions are handled through different build mechanisms.

Applied to files:

src/bun.js/api/BunObject.zig

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/test/v8/v8-module/main.cpp : Register new V8 API test functions in the Init method using NODE_SET_METHOD with exports object

Applied to files:

src/bun.js/api/BunObject.zig

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/src/napi/napi.zig : For each new V8 C++ method, add both GCC/Clang and MSVC mangled symbol names to the V8API struct in src/napi/napi.zig using extern fn declarations

Applied to files:

src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-12-23T06:50:31.577Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 25429
File: src/bun.js/bindings/helpers.h:422-422
Timestamp: 2025-12-23T06:50:31.577Z
Learning: In Bun's C++ bindings, when returning an empty JSC::Identifier and a VM is accessible, prefer using vm.propertyNames->emptyIdentifier over constructing with JSC::Identifier(JSC::Identifier::EmptyIdentifierFlag::EmptyIdentifier). The cached identifier from the VM's property names table is more efficient and consistent with WebKit upgrade patterns. Apply this guidance to src/bun.js/bindings/helpers.h and similar header files in the same bindings directory (i.e., any file that constructs an EmptyIdentifier).

Applied to files:

src/bun.js/bindings/BunObject+exports.h

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `$debug()` for debug logging and `$assert()` for assertions; both are stripped in release builds

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-14T16:07:01.064Z

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 24719
File: docs/bundler/executables.mdx:527-560
Timestamp: 2025-11-14T16:07:01.064Z
Learning: In the Bun repository, certain bundler features like compile with code splitting (--compile --splitting) are CLI-only and not supported in the Bun.build() JavaScript API. Tests for CLI-only features use backend: "cli" flag (e.g., test/bundler/bundler_compile_splitting.test.ts). The CompileBuildConfig interface correctly restricts these with splitting?: never;. When documenting CLI-only bundler features, add a note clarifying they're not available via the programmatic API.

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use private globals and methods with `$` prefix (e.g., `$Array`, `map.$set()`) instead of public JavaScript globals

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-10-19T02:52:37.412Z

Learnt from: theshadow27
Repo: oven-sh/bun PR: 23798
File: packages/bun-otel/tsconfig.json:1-15
Timestamp: 2025-10-19T02:52:37.412Z
Learning: In the Bun repository, packages under packages/ (e.g., bun-otel) can follow a TypeScript-first pattern where package.json exports point directly to .ts files (not compiled .js files). Bun natively runs TypeScript, so consumers import .ts sources directly and receive full type information without needing compiled .d.ts declaration files. For such packages, adding "declaration": true or "outDir" in tsconfig.json is unnecessary and would break the export structure.
<!-- [remove_learning]
ceedde95-980e-4898-a2c6-40ff73913664

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `.$call()` and `.$apply()` instead of `.call()` and `.apply()` to prevent user tampering with function invocation

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-10-14T04:04:47.894Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23636
File: src/shell/ParsedShellScript.zig:15-0
Timestamp: 2025-10-14T04:04:47.894Z
Learning: In src/shell/ParsedShellScript.zig, the JavaScript garbage collector's memory reporting API only allows reporting extra memory allocation once at object creation time. Therefore, `estimated_size_for_gc` is intentionally set once during initialization (via `#computeEstimatedSizeForGC()`) and not updated afterward, even though fields like `args`, `export_env`, and `cwd` may be mutated by methods like `setCwd()`, `setEnv()`, and `take()`. The `estimatedSize()` method returns this cached initial value, while `memoryCost()` computes the size on-demand.

Applied to files:

src/js/builtins/shell.ts
src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to **/js_*.zig : Implement proper memory management with reference counting using `ref()`/`deref()` in JavaScript bindings

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-09-02T17:14:46.924Z

Learnt from: taylordotfish
Repo: oven-sh/bun PR: 22227
File: src/safety/alloc.zig:93-95
Timestamp: 2025-09-02T17:14:46.924Z
Learning: In bun's Zig codebase, they use a custom extension of Zig that supports private field syntax with the `#` prefix (e.g., `#allocator`, `#trace`). This is not standard Zig syntax but is valid in their custom implementation. Fields prefixed with `#` are private fields that cannot be accessed from outside the defining struct.

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to src/**/*.zig : Implement core functionality in Zig, typically in its own directory in `src/`

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : Use `JSC.markBinding(src())` in finalize methods for debugging purposes before calling `deinit()`

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-08-30T09:09:18.384Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 22231
File: src/bundler/bundle_v2.zig:48-48
Timestamp: 2025-08-30T09:09:18.384Z
Learning: In Zig, when a module exports a top-level struct, import("./Module.zig") directly returns that struct type and can be used as a type alias without needing to access a field within the module. This is a common pattern in the Bun codebase.

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-10-14T04:04:17.132Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23636
File: src/shell/interpreter.zig:672-0
Timestamp: 2025-10-14T04:04:17.132Z
Learning: In Bun's shell interpreter (src/shell/interpreter.zig), the JavaScript garbage collector's memory reporting API only allows reporting extra memory allocation once at object creation time. Therefore, `estimated_size_for_gc` is intentionally set once during initialization and not updated afterward, even though fields like `root_io`, `vm_args_utf8`, and `export_env` may be mutated later. The `estimatedSize()` method returns this cached initial value, while `memoryCost()` computes the size on-demand.

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-09-12T18:16:50.754Z

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 22606
File: src/glob/GlobWalker.zig:449-452
Timestamp: 2025-09-12T18:16:50.754Z
Learning: For Bun codebase: prefer using `std.fs.path.sep` over manual platform separator detection, and use `bun.strings.lastIndexOfChar` instead of `std.mem.lastIndexOfScalar` for string operations.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-10-08T13:56:00.875Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23373
File: src/bun.js/api/BunObject.zig:2514-2521
Timestamp: 2025-10-08T13:56:00.875Z
Learning: For Bun codebase: prefer using `bun.path` utilities (e.g., `bun.path.joinAbsStringBuf`, `bun.path.join`) over `std.fs.path` functions for path operations.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-09-05T18:45:29.200Z

Learnt from: markovejnovic
Repo: oven-sh/bun PR: 21728
File: src/valkey/js_valkey.zig:0-0
Timestamp: 2025-09-05T18:45:29.200Z
Learning: In JSValkeyClient.cloneWithoutConnecting() in src/valkey/js_valkey.zig, the address/username/password fields must be repointed to the duplicated connection_strings buffer to avoid use-after-free when the original client is destroyed. The original client properly frees connection_strings in ValkeyClient.deinit().

Applied to files:

src/shell/TraceInterpreter.zig

🧬 Code graph analysis (1)

test/js/bun/shell/trace.test.ts (1)

scripts/utils.mjs (1)

$ (143-161)

🪛 GitHub Check: Lint JavaScript

src/js/builtins/shell.ts

[failure] 5-5: eslint(no-unused-vars)
Interface 'ShellTraceFlags' is declared but never used.

🔇 Additional comments (14)

src/bun.js/bindings/BunObject.cpp (2)

357-357: LGTM! Function creation follows the established pattern.

The traceShellScriptFunction is created correctly, following the same pattern as createParsedShellScript and createShellInterpreterFunction above it.

364-364: LGTM! Correct argument passing.

The trace function is properly appended to the argument list before the shell creation call.

src/bun.js/api/BunObject.zig (1)

19-19: LGTM!

The traceShellScript callback registration follows the established pattern for BunObject callbacks, consistent with other shell-related functions like createParsedShellScript and createShellInterpreter. The export in exportAll() is correctly placed and uses the callbackName helper. Based on learnings, this properly implements the getter function and exports it per the coding guidelines.

Also applies to: 158-158

src/bun.js/bindings/BunObject+exports.h (1)

72-72: LGTM!

The traceShellScript entry in FOR_EACH_CALLBACK correctly registers the host function binding, maintaining alphabetical ordering. This completes the binding path required for the JS-to-Zig callback as per coding guidelines.

test/js/bun/shell/trace.test.ts (3)

1-27: LGTM - Permission constants mirror Zig implementation correctly.

The Permission constants and convenience combinations match the Zig Permission struct exactly, enabling accurate assertion of traced operation flags.

28-48: Good test structure and basic API verification.

The test correctly verifies the result shape and that echo (a builtin with no file access) produces zero operations.

280-295: Good test for subshell cwd isolation.

This test correctly verifies that cwd changes inside subshells don't leak to the parent context, which is important for the permission system's accuracy.

src/js/builtins/shell.ts (3)

48-58: LGTM - Function signature updated correctly.

The function signature now accepts traceShellScript_ and properly type-casts it, following the pattern established for createShellInterpreter and createParsedShellScript.

399-413: LGTM - trace function follows established patterns.

The trace function correctly:

Validates tagged template usage (line 401-402)

Creates parsed shell script

Applies cwd before env (per comment on line 408)

Delegates to the Zig traceShellScript binding

This mirrors the BunShell function pattern while returning synchronously.

428-431: LGTM - trace properly exposed on BunShell.

The trace function is correctly added to BunShell's defineProperties with enumerable: true, consistent with other public API methods.

src/shell/TraceInterpreter.zig (4)

10-35: LGTM - Permission flags correctly mirror Unix standards.

The permission constants correctly use standard Unix octal values for open(2) flags and extended flags for custom operations (EXECUTE, DELETE, MKDIR, CHDIR, ENV) using higher bits to avoid conflicts.

55-131: LGTM - TracedOperation struct is well-designed.

The struct properly tracks all relevant operation metadata with appropriate nullable fields. The toJS method correctly creates a JS object with all fields, and deinit properly frees all owned memory.

134-214: LGTM - TraceResult provides clean result aggregation.

The struct properly manages the operations list, handles error state, and provides correct JS conversion. Memory management in deinit is thorough.

914-940: LGTM - Public trace API is well-structured.

The trace function properly initializes the result and context, walks the AST, and returns the result. The error handling for getcwd with a fallback to "/" is appropriate.

Expand glob patterns like *.txt into matching file paths when tracing. This allows the trace to accurately report which files would be accessed by commands containing wildcards. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

coderabbitai

Actionable comments posted: 1

♻️ Duplicate comments (5)

src/shell/TraceInterpreter.zig (4)

243-254: Potential double-free: export_env ownership is unclear.

The TraceContext takes an optional export_env from the caller but always calls deinit() on it in line 254. If the caller passes their own EnvMap, it will be freed here, potentially causing a double-free when the caller also tries to free it (e.g., line 1076 passes parsed_shell_script.export_env).

🔎 Proposed fix: Don't take ownership of export_env

Either clone the export_env or mark that TraceContext does not own it:

 pub fn deinit(this: *TraceContext) void {
     this.cwd.deinit();
     this.shell_env.deinit();
-    this.export_env.deinit();
+    // Don't deinit export_env - we don't own it
 }

Or if TraceContext should own it, clone on init:

+    // Copy entries from provided export_env if any
+    if (export_env) |e| {
+        var it = e.iterator();
+        while (it.next()) |entry| {
+            ctx.export_env.put(entry.key_ptr.*, entry.value_ptr.*) catch bun.outOfMemory();
+        }
+    }

298-308: Path normalization missing in changeCwd.

For relative paths, the code appends '/' then the path (lines 305-306), which could result in double slashes if cwd already ends with /. Additionally, paths like .. or . aren't normalized, which could lead to incorrect cwd tracking during trace execution.

🔎 Consider using path join for proper normalization

 pub fn changeCwd(this: *TraceContext, new_cwd: []const u8) void {
     if (ResolvePath.Platform.auto.isAbsolute(new_cwd)) {
         this.cwd.clearRetainingCapacity();
         bun.handleOom(this.cwd.appendSlice(new_cwd));
     } else {
-        bun.handleOom(this.cwd.append('/'));
-        bun.handleOom(this.cwd.appendSlice(new_cwd));
+        const parts: []const []const u8 = &.{ this.cwdSlice(), new_cwd };
+        const joined = ResolvePath.joinZ(parts, .auto);
+        this.cwd.clearRetainingCapacity();
+        bun.handleOom(this.cwd.appendSlice(joined[0..joined.len]));
     }
 }

Based on learnings, prefer using bun.path utilities over std.fs.path for path operations.

975-1010: expandDoubleQuoted function is unused dead code.

This function is defined but never called anywhere in the codebase. The SimpleAtom union does not include a .DoubleQuoted case, so there is no AST node type that would invoke this function. It should be removed to reduce maintenance burden.

🔎 Proposed fix

-fn expandDoubleQuoted(ctx: *TraceContext, text: []const u8, out: *std.array_list.Managed(u8)) void {
-    var i: usize = 0;
-    while (i < text.len) {
-        if (text[i] == '$' and i + 1 < text.len) {
-            // Variable expansion
-            const start = i + 1;
-            var end = start;
-            if (text[start] == '{') {
-                // ${var} form
-                end = start + 1;
-                while (end < text.len and text[end] != '}') : (end += 1) {}
-                if (end < text.len) {
-                    const varname = text[start + 1 .. end];
-                    if (ctx.getVar(varname)) |val| {
-                        bun.handleOom(out.appendSlice(val));
-                    }
-                    i = end + 1;
-                    continue;
-                }
-            } else {
-                // $var form
-                while (end < text.len and (std.ascii.isAlphanumeric(text[end]) or text[end] == '_')) : (end += 1) {}
-                if (end > start) {
-                    const varname = text[start..end];
-                    if (ctx.getVar(varname)) |val| {
-                        bun.handleOom(out.appendSlice(val));
-                    }
-                    i = end;
-                    continue;
-                }
-            }
-        }
-        bun.handleOom(out.append(text[i]));
-        i += 1;
-    }
-}

1065-1070: Use-after-free: cwd_slice points to freed memory.

The defer slice.deinit() at line 1068 runs when exiting the brk: block, but slice.slice() is returned as cwd_slice. This frees the memory before it's used in trace() at line 1072, causing undefined behavior.

🔎 Proposed fix

     // Get cwd from parsed script if set
-    const cwd_slice: ?[]const u8 = if (parsed_shell_script.cwd) |c| brk: {
-        const slice = c.toUTF8(bun.default_allocator);
-        defer slice.deinit();
-        break :brk slice.slice();
-    } else null;
+    var cwd_storage: ?bun.String.Slice = null;
+    defer if (cwd_storage) |*s| s.deinit();
+    
+    const cwd_slice: ?[]const u8 = if (parsed_shell_script.cwd) |c| brk: {
+        cwd_storage = c.toUTF8(bun.default_allocator);
+        break :brk cwd_storage.?.slice();
+    } else null;

     var result = trace(

Based on learnings, be careful with allocators in Zig and use defer for cleanup at the proper scope.

test/js/bun/shell/trace.test.ts (1)

250-258: Add platform guard to test using Unix-specific paths.

This test uses Unix-specific paths (/bin/ls, /tmp) without platform guards. Other shell tests in this directory use test.skipIf(isWindows) to handle platform differences.
🔎 Proposed fix
-  test("external command resolves path when available", () => {
+  test.skipIf(process.platform === "win32")("external command resolves path when available", () => {
     const result = $.trace`/bin/ls /tmp`;
Or use the harness helper if available:
import { test, describe, expect } from "bun:test";
import { isWindows } from "harness";

test.skipIf(isWindows)("external command resolves path when available", () => {

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📒 Files selected for processing (2)

src/shell/TraceInterpreter.zig
test/js/bun/shell/trace.test.ts

🧰 Additional context used

📓 Path-based instructions (7)

test/**/*.{js,ts,jsx,tsx}

📄 CodeRabbit inference engine (.cursor/rules/writing-tests.mdc)

test/**/*.{js,ts,jsx,tsx}: Write tests as JavaScript and TypeScript files using Jest-style APIs (test, describe, expect) and import from bun:test
Use test.each and data-driven tests to reduce boilerplate when testing multiple similar cases

Files:

test/js/bun/shell/trace.test.ts

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}

📄 CodeRabbit inference engine (test/CLAUDE.md)

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}: Use bun:test with files that end in *.test.{ts,js,jsx,tsx,mjs,cjs}
Do not write flaky tests. Never wait for time to pass in tests; always wait for the condition to be met instead of using an arbitrary amount of time
Never use hardcoded port numbers in tests. Always use port: 0 to get a random port
Prefer concurrent tests over sequential tests using test.concurrent or describe.concurrent when multiple tests spawn processes or write files, unless it's very difficult to make them concurrent
When spawning Bun processes in tests, use bunExe and bunEnv from harness to ensure the same build of Bun is used and debug logging is silenced
Use -e flag for single-file tests when spawning Bun processes
Use tempDir() from harness to create temporary directories with files for multi-file tests instead of creating files manually
Prefer async/await over callbacks in tests
When callbacks must be used and it's just a single callback, use Promise.withResolvers to create a promise that can be resolved or rejected from a callback
Do not set a timeout on tests. Bun already has timeouts
Use Buffer.alloc(count, fill).toString() instead of 'A'.repeat(count) to create repetitive strings in tests, as ''.repeat is very slow in debug JavaScriptCore builds
Use describe blocks for grouping related tests
Always use await using or using to ensure proper resource cleanup in tests for APIs like Bun.listen, Bun.connect, Bun.spawn, Bun.serve, etc
Always check exit codes and test error scenarios in error tests
Use describe.each() for parameterized tests
Use toMatchSnapshot() for snapshot testing
Use beforeAll(), afterEach(), beforeEach() for setup/teardown in tests
Track resources (servers, clients) in arrays for cleanup in afterEach()

Files:

test/js/bun/shell/trace.test.ts

**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

**/*.test.ts?(x): Never use bun test directly - always use bun bd test to run tests with debug build changes
For single-file tests, prefer -e flag over tempDir
For multi-file tests, prefer tempDir and Bun.spawn over single-file tests
Use normalizeBunSnapshot to normalize snapshot output of tests
Never write tests that check for 'panic', 'uncaught exception', or similar strings in test output
Use tempDir from harness to create temporary directories - do not use tmpdirSync or fs.mkdtempSync
When spawning processes in tests, expect stdout before expecting exit code for more useful error messages on test failure
Do not write flaky tests - do not use setTimeout in tests; instead await the condition to be met
Verify tests fail with USE_SYSTEM_BUN=1 bun test <file> and pass with bun bd test <file> - tests are invalid if they pass with USE_SYSTEM_BUN=1
Test files must end with .test.ts or .test.tsx
Avoid shell commands like find or grep in tests - use Bun's Glob and built-in tools instead

Files:

test/js/bun/shell/trace.test.ts

test/**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

Always use port: 0 in tests - do not hardcode ports or use custom random port number functions

Files:

test/js/bun/shell/trace.test.ts

src/**/*.{cpp,zig}

📄 CodeRabbit inference engine (.cursor/rules/building-bun.mdc)

src/**/*.{cpp,zig}: Use bun bd or bun run build:debug to build debug versions for C++ and Zig source files; creates debug build at ./build/debug/bun-debug
Run tests using bun bd test <test-file> with the debug build; never use bun test directly as it will not include your changes
Execute files using bun bd <file> <...args>; never use bun <file> directly as it will not include your changes
Enable debug logs for specific scopes using BUN_DEBUG_$(SCOPE)=1 environment variable
Code generation happens automatically as part of the build process; no manual code generation commands are required

Files:

src/shell/TraceInterpreter.zig

src/**/*.zig

📄 CodeRabbit inference engine (.cursor/rules/building-bun.mdc)

Use bun.Output.scoped(.${SCOPE}, .hidden) for creating debug logs in Zig code

Implement core functionality in Zig, typically in its own directory in src/

src/**/*.zig: Private fields in Zig are fully supported using the # prefix: struct { #foo: u32 };
Use decl literals in Zig for declaration initialization: const decl: Decl = .{ .binding = 0, .value = 0 };
Prefer @import at the bottom of the file (auto formatter will move them automatically)

Files:

src/shell/TraceInterpreter.zig

**/*.zig

📄 CodeRabbit inference engine (.cursor/rules/zig-javascriptcore-classes.mdc)

**/*.zig: Expose generated bindings in Zig structs using pub const js = JSC.Codegen.JS<ClassName> with trait conversion methods: toJS, fromJS, and fromJSDirect
Use consistent parameter name globalObject instead of ctx in Zig constructor and method implementations
Use bun.JSError!JSValue return type for Zig methods and constructors to enable proper error handling and exception propagation
Implement resource cleanup using deinit() method that releases resources, followed by finalize() called by the GC that invokes deinit() and frees the pointer
Use JSC.markBinding(@src()) in finalize methods for debugging purposes before calling deinit()
For methods returning cached properties in Zig, declare external C++ functions using extern fn and callconv(JSC.conv) calling convention
Implement getter functions with naming pattern get<PropertyName> in Zig that accept this and globalObject parameters and return JSC.JSValue
Access JavaScript CallFrame arguments using callFrame.argument(i), check argument count with callFrame.argumentCount(), and get this with callFrame.thisValue()
For reference-counted objects, use .deref() in finalize instead of destroy() to release references to other JS objects

In Zig code, be careful with allocators and use defer for cleanup

Files:

src/shell/TraceInterpreter.zig

🧠 Learnings (29)

📓 Common learnings

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Add tests for new Bun runtime functionality

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/test/v8/v8.test.ts : Add corresponding test cases to test/v8/v8.test.ts using checkSameOutput() function to compare Node.js and Bun output

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : When spawning Bun processes in tests, use `bunExe` and `bunEnv` from `harness` to ensure the same build of Bun is used and debug logging is silenced

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:50.422Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/writing-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:50.422Z
Learning: Applies to test/**/*.{js,ts,jsx,tsx} : Write tests as JavaScript and TypeScript files using Jest-style APIs (`test`, `describe`, `expect`) and import from `bun:test`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Never use `bun test` directly - always use `bun bd test` to run tests with debug build changes

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/dev/esm.test.ts : Organize ESM tests in esm.test.ts for tests about various ESM features in development mode

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Avoid shell commands like `find` or `grep` in tests - use Bun's Glob and built-in tools instead

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-19T02:44:46.354Z

Learnt from: theshadow27
Repo: oven-sh/bun PR: 23798
File: packages/bun-otel/context-propagation.test.ts:1-1
Timestamp: 2025-10-19T02:44:46.354Z
Learning: In the Bun repository, standalone packages under packages/ (e.g., bun-vscode, bun-inspector-protocol, bun-plugin-yaml, bun-plugin-svelte, bun-debug-adapter-protocol, bun-otel) co-locate their tests with package source code using *.test.ts files. This follows standard npm/monorepo patterns. The test/ directory hierarchy (test/js/bun/, test/cli/, test/js/node/) is reserved for testing Bun's core runtime APIs and built-in functionality, not standalone packages.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Verify tests fail with `USE_SYSTEM_BUN=1 bun test <file>` and pass with `bun bd test <file>` - tests are invalid if they pass with USE_SYSTEM_BUN=1

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/dev/sourcemap.test.ts : Organize source-map tests in sourcemap.test.ts for tests verifying source-maps are correct

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Add tests for new Bun runtime functionality

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `process.platform` and `process.arch` for platform detection; these values are inlined and dead-code eliminated at build time

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For multi-file tests, prefer `tempDir` and `Bun.spawn` over single-file tests

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/js/node/test/{parallel,sequential}/*.js : For test/js/node/test/{parallel,sequential}/*.js files without a .test extension, use `bun bd <file>` instead of `bun bd test <file>` since these expect exit code 0 and don't use bun's test runner

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For single-file tests, prefer `-e` flag over `tempDir`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `-e` flag for single-file tests when spawning Bun processes

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-26T01:32:04.844Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 24082
File: test/cli/test/coverage.test.ts:60-112
Timestamp: 2025-10-26T01:32:04.844Z
Learning: In the Bun repository test files (test/cli/test/*.test.ts), when spawning Bun CLI commands with Bun.spawnSync for testing, prefer using stdio: ["inherit", "inherit", "inherit"] to inherit stdio streams rather than piping them.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:50.422Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/writing-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:50.422Z
Learning: Applies to test/cli/**/*.{js,ts,jsx,tsx} : When testing Bun as a CLI, use the `spawn` API from `bun` with the `bunExe()` and `bunEnv` from `harness` to execute Bun commands and validate exit codes, stdout, and stderr

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `bun:test` with files that end in `*.test.{ts,js,jsx,tsx,mjs,cjs}`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-09-12T18:16:50.754Z

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 22606
File: src/glob/GlobWalker.zig:449-452
Timestamp: 2025-09-12T18:16:50.754Z
Learning: For Bun codebase: prefer using `std.fs.path.sep` over manual platform separator detection, and use `bun.strings.lastIndexOfChar` instead of `std.mem.lastIndexOfScalar` for string operations.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-10-08T13:56:00.875Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23373
File: src/bun.js/api/BunObject.zig:2514-2521
Timestamp: 2025-10-08T13:56:00.875Z
Learning: For Bun codebase: prefer using `bun.path` utilities (e.g., `bun.path.joinAbsStringBuf`, `bun.path.join`) over `std.fs.path` functions for path operations.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-09-05T18:45:29.200Z

Learnt from: markovejnovic
Repo: oven-sh/bun PR: 21728
File: src/valkey/js_valkey.zig:0-0
Timestamp: 2025-09-05T18:45:29.200Z
Learning: In JSValkeyClient.cloneWithoutConnecting() in src/valkey/js_valkey.zig, the address/username/password fields must be repointed to the duplicated connection_strings buffer to avoid use-after-free when the original client is destroyed. The original client properly frees connection_strings in ValkeyClient.deinit().

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-10-14T04:04:47.894Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23636
File: src/shell/ParsedShellScript.zig:15-0
Timestamp: 2025-10-14T04:04:47.894Z
Learning: In src/shell/ParsedShellScript.zig, the JavaScript garbage collector's memory reporting API only allows reporting extra memory allocation once at object creation time. Therefore, `estimated_size_for_gc` is intentionally set once during initialization (via `#computeEstimatedSizeForGC()`) and not updated afterward, even though fields like `args`, `export_env`, and `cwd` may be mutated by methods like `setCwd()`, `setEnv()`, and `take()`. The `estimatedSize()` method returns this cached initial value, while `memoryCost()` computes the size on-demand.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.zig : In Zig code, be careful with allocators and use defer for cleanup

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to **/js_*.zig : Implement proper memory management with reference counting using `ref()`/`deref()` in JavaScript bindings

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : Use `JSC.markBinding(src())` in finalize methods for debugging purposes before calling `deinit()`

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-10-24T10:43:09.398Z

Learnt from: fmguerreiro
Repo: oven-sh/bun PR: 23774
File: src/install/PackageManager/updatePackageJSONAndInstall.zig:548-548
Timestamp: 2025-10-24T10:43:09.398Z
Learning: In Bun's Zig codebase, the `as(usize, intCast(...))` cast pattern triggers a Zig compiler bug that causes compilation to hang indefinitely when used in complex control flow contexts (loops + short-circuit operators + optional unwrapping). Avoid this pattern and use simpler alternatives like just `intCast(...)` if type casting is necessary.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : For reference-counted objects, use `.deref()` in finalize instead of `destroy()` to release references to other JS objects

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-09-02T18:25:27.976Z

Learnt from: taylordotfish
Repo: oven-sh/bun PR: 22227
File: src/allocators/allocation_scope.zig:284-314
Timestamp: 2025-09-02T18:25:27.976Z
Learning: In bun's custom Zig implementation, the `#` prefix for private fields is valid syntax and should not be flagged as invalid. The syntax `#fieldname` creates private fields that cannot be accessed from outside the defining struct, and usage like `self.#fieldname` is correct within the same struct. This applies to fields like `#parent`, `#state`, `#allocator`, `#trace`, etc. throughout the codebase.

Applied to files:

src/shell/TraceInterpreter.zig

🧬 Code graph analysis (1)

test/js/bun/shell/trace.test.ts (2)

scripts/utils.mjs (1)

$ (143-161)

scripts/glob-sources.mjs (1)

paths (9-9)

🔇 Additional comments (5)

src/shell/TraceInterpreter.zig (3)

8-52: LGTM! Well-structured permission flags and stream enum.

The permission constants use proper octal notation mirroring Unix standards, and the Stream enum provides clean JavaScript conversion. The organization is clear and maintainable.

812-908: LGTM! Glob expansion with proper memory management.

The glob expansion correctly handles memory:

Duplicates matched paths to the caller's allocator (line 872)

Frees the original pattern when matches are found (line 888)

Cleans up on error paths (line 896)

Properly deinitializes the matched_paths list

669-710: LGTM! Correct memory handling for redirections.

The function properly duplicates the path for stderr when both stdout and stderr redirect to the same file (line 687), ensuring each field in RedirectInfo has independent ownership. The caller (traceCmd) correctly frees all paths via defer (lines 467-471).

test/js/bun/shell/trace.test.ts (2)

1-48: LGTM! Well-structured test setup.

The permission constants correctly mirror the Zig implementation, and the basic test validates the trace result structure comprehensively.

49-327: LGTM! Comprehensive test coverage.

The test suite thoroughly exercises the trace API across multiple scenarios:

Builtin commands (cat, rm, mkdir, touch, cp, mv, ls, cd, export, echo)

Redirections with proper stream markers (stdin/stdout/stderr)

Binary operators (&&, ||) and pipelines

Expansions (brace, tilde, glob)

Subshell cwd isolation

Template literal interpolation

The tests validate both operation counts and specific operation properties (path, flags, cwd, stream, command), ensuring correct behavior.

Based on learnings, comprehensive tests for new Bun runtime functionality are essential.

External commands now include an `args` array containing all command arguments (excluding the command name itself). This enables runtime wrappers to implement command-specific argument parsing for file path detection. Example: ```js const result = $.trace`grep -r 'pattern' src/`; result.operations[0].args // ["-r", "pattern", "src/"] ``` 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

- Environment variable assignments now include the variable name in envVar - Optional properties are now omitted instead of set to null - Cleaner output: only flags and cwd are always present - Add test for multiple env var tracking 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

- Replace envVar field with env: Record<string, string> showing accumulated environment state at each operation - Add dynamic: true flag for non-statically-analyzable values (command substitution, $1, $@, etc.) - Handle export builtin to parse FOO=value arguments - Environment variables accumulate as commands execute Example: ```js const result = $.trace`FOO=1 BAR=2 cat file.txt`; // Operations show accumulated env: // op1: { env: { FOO: "1" } } // op2: { env: { FOO: "1", BAR: "2" } } // op3: { env: { FOO: "1", BAR: "2" }, path: "file.txt" } ``` 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

coderabbitai

Actionable comments posted: 1

♻️ Duplicate comments (8)

test/js/bun/shell/trace.test.ts (2)

273-281: Add platform guard for Unix-specific path /bin/ls.

This test uses /bin/ls which doesn't exist on Windows. While $.trace doesn't execute commands, the test expectations are Unix-specific.

🔎 Proposed fix

+import { isWindows } from "harness";
+
 // At the test definition:
-  test("external command resolves path when available", () => {
+  test.skipIf(isWindows)("external command resolves path when available", () => {

386-405: Use tempDir from harness and Bun APIs instead of manual /tmp usage.

Per coding guidelines, use tempDir() from harness for temporary directories and prefer Bun APIs over Node.js require("fs"). This also addresses the Unix-specific /tmp path.

🔎 Proposed fix

+import { tempDir } from "harness";
+
-  test("expands glob patterns to matching files", () => {
-    // Create test files for glob expansion
-    const fs = require("fs");
-    const testDir = "/tmp/trace-glob-test";
-    fs.mkdirSync(testDir, { recursive: true });
-    fs.writeFileSync(`${testDir}/a.txt`, "");
-    fs.writeFileSync(`${testDir}/b.txt`, "");
-    fs.writeFileSync(`${testDir}/c.txt`, "");
+  test("expands glob patterns to matching files", async () => {
+    const testDir = tempDir();
+    await Bun.write(`${testDir}/a.txt`, "");
+    await Bun.write(`${testDir}/b.txt`, "");
+    await Bun.write(`${testDir}/c.txt`, "");

     const result = $.trace`cat ${testDir}/*.txt`;
     expect(result.success).toBe(true);

     const readOps = result.operations.filter(op => op.flags === READ);
     expect(readOps.length).toBe(3);
     const paths = readOps.map(op => op.path).sort();
     expect(paths).toEqual([`${testDir}/a.txt`, `${testDir}/b.txt`, `${testDir}/c.txt`]);
-
-    // Cleanup
-    fs.rmSync(testDir, { recursive: true });
   });

As per coding guidelines, use tempDir() from harness to create temporary directories and prefer Bun APIs over Node.js fs module.

src/js/builtins/shell.ts (1)

5-30: Remove or suppress the unused ShellTraceFlags interface.

Static analysis reports this interface as declared but never used. Since ShellTraceOperation.flags is typed as number, consider either removing the interface (the constants are documented in Zig) or suppressing the lint warning.

🔎 Option 1: Remove the interface

The permission constants are already documented in TraceInterpreter.zig and mirrored in the test file. The interface can be removed if it's purely documentary.
🔎 Option 2: Suppress the warning
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
 interface ShellTraceFlags {

src/shell/TraceInterpreter.zig (5)

468-478: Path normalization missing in changeCwd.

For relative paths, the code appends / then the path, which could result in double slashes if cwd already ends with /. Additionally, paths like .. or . aren't normalized.

🔎 Proposed fix using path join

 pub fn changeCwd(this: *TraceContext, new_cwd: []const u8) void {
     if (ResolvePath.Platform.auto.isAbsolute(new_cwd)) {
         this.cwd.clearRetainingCapacity();
         bun.handleOom(this.cwd.appendSlice(new_cwd));
     } else {
-        bun.handleOom(this.cwd.append('/'));
-        bun.handleOom(this.cwd.appendSlice(new_cwd));
+        const parts: []const []const u8 = &.{ this.cwdSlice(), new_cwd };
+        const joined = ResolvePath.joinZ(parts, .auto);
+        this.cwd.clearRetainingCapacity();
+        bun.handleOom(this.cwd.appendSlice(joined[0..joined.len]));
     }
 }

1190-1225: Remove unused expandDoubleQuoted function.

This function is defined but never called anywhere in the codebase. The SimpleAtom union does not include a .DoubleQuoted case, so there's no AST node type that would invoke this function.

🔎 Proposed fix

-fn expandDoubleQuoted(ctx: *TraceContext, text: []const u8, out: *std.array_list.Managed(u8)) void {
-    var i: usize = 0;
-    while (i < text.len) {
-        if (text[i] == '$' and i + 1 < text.len) {
-            // Variable expansion
-            const start = i + 1;
-            var end = start;
-            if (text[start] == '{') {
-                // ${var} form
-                end = start + 1;
-                while (end < text.len and text[end] != '}') : (end += 1) {}
-                if (end < text.len) {
-                    const varname = text[start + 1 .. end];
-                    if (ctx.getVar(varname)) |val| {
-                        bun.handleOom(out.appendSlice(val));
-                    }
-                    i = end + 1;
-                    continue;
-                }
-            } else {
-                // $var form
-                while (end < text.len and (std.ascii.isAlphanumeric(text[end]) or text[end] == '_')) : (end += 1) {}
-                if (end > start) {
-                    const varname = text[start..end];
-                    if (ctx.getVar(varname)) |val| {
-                        bun.handleOom(out.appendSlice(val));
-                    }
-                    i = end;
-                    continue;
-                }
-            }
-        }
-        bun.handleOom(out.append(text[i]));
-        i += 1;
-    }
-}

1280-1285: Use-after-free: cwd_slice points to freed memory.

The defer slice.deinit() at line 1283 runs when exiting the brk: block, but slice.slice() is returned as cwd_slice. This frees the memory before it's used in trace() at line 1287.

This was flagged in a previous review as "addressed" but the code still shows the same pattern.

🔎 Proposed fix

     // Get cwd from parsed script if set
-    const cwd_slice: ?[]const u8 = if (parsed_shell_script.cwd) |c| brk: {
-        const slice = c.toUTF8(bun.default_allocator);
-        defer slice.deinit();
-        break :brk slice.slice();
-    } else null;
+    var cwd_storage: ?bun.String.Slice = null;
+    defer if (cwd_storage) |*s| s.deinit();
+    
+    const cwd_slice: ?[]const u8 = if (parsed_shell_script.cwd) |c| brk: {
+        cwd_storage = c.toUTF8(bun.default_allocator);
+        break :brk cwd_storage.?.slice();
+    } else null;

     var result = trace(

749-772: mv and cp only handle two-argument form.

The current implementation handles mv src dst and cp src dst but not multi-file forms like mv file1 file2 dir/ or cp file1 file2 dir/. This may under-report required permissions for multi-file operations.

🔎 Proposed enhancement for multi-file support

         .mv => {
-            // mv moves files (read+delete source, create dest)
             var file_args = extractFileArgs(ctx, cmd);
             defer freeFileArgs(ctx, &file_args);

-            if (file_args.items.len >= 1) {
-                ctx.addOperation(Permission.READ | Permission.DELETE, file_args.items[0], null);
-            }
-            if (file_args.items.len >= 2) {
-                ctx.addOperation(Permission.CREATE, file_args.items[1], null);
+            if (file_args.items.len >= 2) {
+                // Last arg is destination
+                const dest = file_args.items[file_args.items.len - 1];
+                // All other args are sources
+                for (file_args.items[0..file_args.items.len - 1]) |src| {
+                    ctx.addOperation(Permission.READ | Permission.DELETE, src, null);
+                }
+                ctx.addOperation(Permission.CREATE, dest, null);
             }
         },

317-338: Fix double-free in export_env handling between TraceContext and ParsedShellScript.

traceShellScript passes parsed_shell_script.export_env directly to trace(), which creates a TraceContext that takes ownership without cloning (line 330). Both TraceContext.deinit() (line 343) and ParsedShellScript.finalize() will call deinit() on the same export_env, causing a double-free. Either clone the export_env before passing it (following the pattern at interpreter.zig:508), or call parsed_shell_script.take() to transfer ownership and null the field.

📜 Review details

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Review profile: ASSERTIVE

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📥 Commits

Reviewing files that changed from the base of the PR and between d70fadd and a8c2c7b.

📒 Files selected for processing (3)

src/js/builtins/shell.ts
src/shell/TraceInterpreter.zig
test/js/bun/shell/trace.test.ts

🧰 Additional context used

📓 Path-based instructions (9)

src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js}

📄 CodeRabbit inference engine (src/js/CLAUDE.md)

src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js}: Use .$call() and .$apply() instead of .call() and .apply() to prevent user tampering with function invocation
Use string literal require() statements only; dynamic requires are not permitted
Export modules using export default { ... } syntax; modules are NOT ES modules
Use JSC intrinsics (prefixed with $) such as $Array.from(), $isCallable(), and $newArrayWithSize() for performance-critical operations
Use private globals and methods with $ prefix (e.g., $Array, map.$set()) instead of public JavaScript globals
Use $debug() for debug logging and $assert() for assertions; both are stripped in release builds
Validate function arguments using validators from internal/validators and throw $ERR_* error codes for invalid arguments
Use process.platform and process.arch for platform detection; these values are inlined and dead-code eliminated at build time

Files:

src/js/builtins/shell.ts

src/js/{builtins,node,bun,thirdparty,internal}/**/*.ts

📄 CodeRabbit inference engine (src/js/CLAUDE.md)

Builtin functions must include this parameter typing in TypeScript to enable direct method binding in C++

Files:

src/js/builtins/shell.ts

test/**/*.{js,ts,jsx,tsx}

📄 CodeRabbit inference engine (.cursor/rules/writing-tests.mdc)

test/**/*.{js,ts,jsx,tsx}: Write tests as JavaScript and TypeScript files using Jest-style APIs (test, describe, expect) and import from bun:test
Use test.each and data-driven tests to reduce boilerplate when testing multiple similar cases

Files:

test/js/bun/shell/trace.test.ts

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}

📄 CodeRabbit inference engine (test/CLAUDE.md)

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}: Use bun:test with files that end in *.test.{ts,js,jsx,tsx,mjs,cjs}
Do not write flaky tests. Never wait for time to pass in tests; always wait for the condition to be met instead of using an arbitrary amount of time
Never use hardcoded port numbers in tests. Always use port: 0 to get a random port
Prefer concurrent tests over sequential tests using test.concurrent or describe.concurrent when multiple tests spawn processes or write files, unless it's very difficult to make them concurrent
When spawning Bun processes in tests, use bunExe and bunEnv from harness to ensure the same build of Bun is used and debug logging is silenced
Use -e flag for single-file tests when spawning Bun processes
Use tempDir() from harness to create temporary directories with files for multi-file tests instead of creating files manually
Prefer async/await over callbacks in tests
When callbacks must be used and it's just a single callback, use Promise.withResolvers to create a promise that can be resolved or rejected from a callback
Do not set a timeout on tests. Bun already has timeouts
Use Buffer.alloc(count, fill).toString() instead of 'A'.repeat(count) to create repetitive strings in tests, as ''.repeat is very slow in debug JavaScriptCore builds
Use describe blocks for grouping related tests
Always use await using or using to ensure proper resource cleanup in tests for APIs like Bun.listen, Bun.connect, Bun.spawn, Bun.serve, etc
Always check exit codes and test error scenarios in error tests
Use describe.each() for parameterized tests
Use toMatchSnapshot() for snapshot testing
Use beforeAll(), afterEach(), beforeEach() for setup/teardown in tests
Track resources (servers, clients) in arrays for cleanup in afterEach()

Files:

test/js/bun/shell/trace.test.ts

**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

**/*.test.ts?(x): Never use bun test directly - always use bun bd test to run tests with debug build changes
For single-file tests, prefer -e flag over tempDir
For multi-file tests, prefer tempDir and Bun.spawn over single-file tests
Use normalizeBunSnapshot to normalize snapshot output of tests
Never write tests that check for 'panic', 'uncaught exception', or similar strings in test output
Use tempDir from harness to create temporary directories - do not use tmpdirSync or fs.mkdtempSync
When spawning processes in tests, expect stdout before expecting exit code for more useful error messages on test failure
Do not write flaky tests - do not use setTimeout in tests; instead await the condition to be met
Verify tests fail with USE_SYSTEM_BUN=1 bun test <file> and pass with bun bd test <file> - tests are invalid if they pass with USE_SYSTEM_BUN=1
Test files must end with .test.ts or .test.tsx
Avoid shell commands like find or grep in tests - use Bun's Glob and built-in tools instead

Files:

test/js/bun/shell/trace.test.ts

test/**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

Always use port: 0 in tests - do not hardcode ports or use custom random port number functions

Files:

test/js/bun/shell/trace.test.ts

src/**/*.{cpp,zig}

📄 CodeRabbit inference engine (.cursor/rules/building-bun.mdc)

src/**/*.{cpp,zig}: Use bun bd or bun run build:debug to build debug versions for C++ and Zig source files; creates debug build at ./build/debug/bun-debug
Run tests using bun bd test <test-file> with the debug build; never use bun test directly as it will not include your changes
Execute files using bun bd <file> <...args>; never use bun <file> directly as it will not include your changes
Enable debug logs for specific scopes using BUN_DEBUG_$(SCOPE)=1 environment variable
Code generation happens automatically as part of the build process; no manual code generation commands are required

Files:

src/shell/TraceInterpreter.zig

src/**/*.zig

📄 CodeRabbit inference engine (.cursor/rules/building-bun.mdc)

Use bun.Output.scoped(.${SCOPE}, .hidden) for creating debug logs in Zig code

Implement core functionality in Zig, typically in its own directory in src/

src/**/*.zig: Private fields in Zig are fully supported using the # prefix: struct { #foo: u32 };
Use decl literals in Zig for declaration initialization: const decl: Decl = .{ .binding = 0, .value = 0 };
Prefer @import at the bottom of the file (auto formatter will move them automatically)

Files:

src/shell/TraceInterpreter.zig

**/*.zig

📄 CodeRabbit inference engine (.cursor/rules/zig-javascriptcore-classes.mdc)

**/*.zig: Expose generated bindings in Zig structs using pub const js = JSC.Codegen.JS<ClassName> with trait conversion methods: toJS, fromJS, and fromJSDirect
Use consistent parameter name globalObject instead of ctx in Zig constructor and method implementations
Use bun.JSError!JSValue return type for Zig methods and constructors to enable proper error handling and exception propagation
Implement resource cleanup using deinit() method that releases resources, followed by finalize() called by the GC that invokes deinit() and frees the pointer
Use JSC.markBinding(@src()) in finalize methods for debugging purposes before calling deinit()
For methods returning cached properties in Zig, declare external C++ functions using extern fn and callconv(JSC.conv) calling convention
Implement getter functions with naming pattern get<PropertyName> in Zig that accept this and globalObject parameters and return JSC.JSValue
Access JavaScript CallFrame arguments using callFrame.argument(i), check argument count with callFrame.argumentCount(), and get this with callFrame.thisValue()
For reference-counted objects, use .deref() in finalize instead of destroy() to release references to other JS objects

In Zig code, be careful with allocators and use defer for cleanup

Files:

src/shell/TraceInterpreter.zig

🧠 Learnings (40)

📓 Common learnings

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Add tests for new Bun runtime functionality

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to src/bun.js/bindings/**/*.cpp : Cache structures in ZigGlobalObject for JavaScript class bindings

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/test/v8/v8.test.ts : Add corresponding test cases to test/v8/v8.test.ts using checkSameOutput() function to compare Node.js and Bun output

Applied to files:

src/js/builtins/shell.ts
test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-14T16:07:01.064Z

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 24719
File: docs/bundler/executables.mdx:527-560
Timestamp: 2025-11-14T16:07:01.064Z
Learning: In the Bun repository, certain bundler features like compile with code splitting (--compile --splitting) are CLI-only and not supported in the Bun.build() JavaScript API. Tests for CLI-only features use backend: "cli" flag (e.g., test/bundler/bundler_compile_splitting.test.ts). The CompileBuildConfig interface correctly restricts these with splitting?: never;. When documenting CLI-only bundler features, add a note clarifying they're not available via the programmatic API.

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `$debug()` for debug logging and `$assert()` for assertions; both are stripped in release builds

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.ts : Builtin functions must include `this` parameter typing in TypeScript to enable direct method binding in C++

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `process.platform` and `process.arch` for platform detection; these values are inlined and dead-code eliminated at build time

Applied to files:

src/js/builtins/shell.ts
test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use JSC intrinsics (prefixed with `$`) such as `$Array.from()`, `$isCallable()`, and `$newArrayWithSize()` for performance-critical operations

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `.$call()` and `.$apply()` instead of `.call()` and `.apply()` to prevent user tampering with function invocation

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use private globals and methods with `$` prefix (e.g., `$Array`, `map.$set()`) instead of public JavaScript globals

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-10-19T02:52:37.412Z

Learnt from: theshadow27
Repo: oven-sh/bun PR: 23798
File: packages/bun-otel/tsconfig.json:1-15
Timestamp: 2025-10-19T02:52:37.412Z
Learning: In the Bun repository, packages under packages/ (e.g., bun-otel) can follow a TypeScript-first pattern where package.json exports point directly to .ts files (not compiled .js files). Bun natively runs TypeScript, so consumers import .ts sources directly and receive full type information without needing compiled .d.ts declaration files. For such packages, adding "declaration": true or "outDir" in tsconfig.json is unnecessary and would break the export structure.
<!-- [remove_learning]
ceedde95-980e-4898-a2c6-40ff73913664

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Write JS builtins for Bun's Node.js compatibility and APIs, and run `bun bd` after changes

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-10-14T04:04:47.894Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23636
File: src/shell/ParsedShellScript.zig:15-0
Timestamp: 2025-10-14T04:04:47.894Z
Learning: In src/shell/ParsedShellScript.zig, the JavaScript garbage collector's memory reporting API only allows reporting extra memory allocation once at object creation time. Therefore, `estimated_size_for_gc` is intentionally set once during initialization (via `#computeEstimatedSizeForGC()`) and not updated afterward, even though fields like `args`, `export_env`, and `cwd` may be mutated by methods like `setCwd()`, `setEnv()`, and `take()`. The `estimatedSize()` method returns this cached initial value, while `memoryCost()` computes the size on-demand.

Applied to files:

src/js/builtins/shell.ts
src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:35:50.422Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/writing-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:50.422Z
Learning: Applies to test/cli/**/*.{js,ts,jsx,tsx} : When testing Bun as a CLI, use the `spawn` API from `bun` with the `bunExe()` and `bunEnv` from `harness` to execute Bun commands and validate exit codes, stdout, and stderr

Applied to files:

src/js/builtins/shell.ts
test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/dev/esm.test.ts : Organize ESM tests in esm.test.ts for tests about various ESM features in development mode

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : When spawning Bun processes in tests, use `bunExe` and `bunEnv` from `harness` to ensure the same build of Bun is used and debug logging is silenced

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Avoid shell commands like `find` or `grep` in tests - use Bun's Glob and built-in tools instead

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Add tests for new Bun runtime functionality

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-19T02:44:46.354Z

Learnt from: theshadow27
Repo: oven-sh/bun PR: 23798
File: packages/bun-otel/context-propagation.test.ts:1-1
Timestamp: 2025-10-19T02:44:46.354Z
Learning: In the Bun repository, standalone packages under packages/ (e.g., bun-vscode, bun-inspector-protocol, bun-plugin-yaml, bun-plugin-svelte, bun-debug-adapter-protocol, bun-otel) co-locate their tests with package source code using *.test.ts files. This follows standard npm/monorepo patterns. The test/ directory hierarchy (test/js/bun/, test/cli/, test/js/node/) is reserved for testing Bun's core runtime APIs and built-in functionality, not standalone packages.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Verify tests fail with `USE_SYSTEM_BUN=1 bun test <file>` and pass with `bun bd test <file>` - tests are invalid if they pass with USE_SYSTEM_BUN=1

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `-e` flag for single-file tests when spawning Bun processes

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For multi-file tests, prefer `tempDir` and `Bun.spawn` over single-file tests

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/dev/sourcemap.test.ts : Organize source-map tests in sourcemap.test.ts for tests verifying source-maps are correct

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/js/node/test/{parallel,sequential}/*.js : For test/js/node/test/{parallel,sequential}/*.js files without a .test extension, use `bun bd <file>` instead of `bun bd test <file>` since these expect exit code 0 and don't use bun's test runner

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For single-file tests, prefer `-e` flag over `tempDir`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-26T01:32:04.844Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 24082
File: test/cli/test/coverage.test.ts:60-112
Timestamp: 2025-10-26T01:32:04.844Z
Learning: In the Bun repository test files (test/cli/test/*.test.ts), when spawning Bun CLI commands with Bun.spawnSync for testing, prefer using stdio: ["inherit", "inherit", "inherit"] to inherit stdio streams rather than piping them.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `tempDir()` from harness to create temporary directories with files for multi-file tests instead of creating files manually

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Use `tempDir` from `harness` to create temporary directories - do not use `tmpdirSync` or `fs.mkdtempSync`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/**/*.test.ts : Use `dev.write()`, `dev.patch()`, and `dev.delete()` to mutate the filesystem instead of `node:fs` APIs, as dev server functions are hooked to wait for hot-reload and notify clients

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Always use `await using` or `using` to ensure proper resource cleanup in tests for APIs like Bun.listen, Bun.connect, Bun.spawn, Bun.serve, etc

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:50.422Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/writing-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:50.422Z
Learning: Applies to test/**/*.{js,ts,jsx,tsx} : Write tests as JavaScript and TypeScript files using Jest-style APIs (`test`, `describe`, `expect`) and import from `bun:test`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `bun:test` with files that end in `*.test.{ts,js,jsx,tsx,mjs,cjs}`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-14T04:04:17.132Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23636
File: src/shell/interpreter.zig:672-0
Timestamp: 2025-10-14T04:04:17.132Z
Learning: In Bun's shell interpreter (src/shell/interpreter.zig), the JavaScript garbage collector's memory reporting API only allows reporting extra memory allocation once at object creation time. Therefore, `estimated_size_for_gc` is intentionally set once during initialization and not updated afterward, even though fields like `root_io`, `vm_args_utf8`, and `export_env` may be mutated later. The `estimatedSize()` method returns this cached initial value, while `memoryCost()` computes the size on-demand.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-09-12T18:16:50.754Z

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 22606
File: src/glob/GlobWalker.zig:449-452
Timestamp: 2025-09-12T18:16:50.754Z
Learning: For Bun codebase: prefer using `std.fs.path.sep` over manual platform separator detection, and use `bun.strings.lastIndexOfChar` instead of `std.mem.lastIndexOfScalar` for string operations.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-10-08T13:56:00.875Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23373
File: src/bun.js/api/BunObject.zig:2514-2521
Timestamp: 2025-10-08T13:56:00.875Z
Learning: For Bun codebase: prefer using `bun.path` utilities (e.g., `bun.path.joinAbsStringBuf`, `bun.path.join`) over `std.fs.path` functions for path operations.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-09-05T18:45:29.200Z

Learnt from: markovejnovic
Repo: oven-sh/bun PR: 21728
File: src/valkey/js_valkey.zig:0-0
Timestamp: 2025-09-05T18:45:29.200Z
Learning: In JSValkeyClient.cloneWithoutConnecting() in src/valkey/js_valkey.zig, the address/username/password fields must be repointed to the duplicated connection_strings buffer to avoid use-after-free when the original client is destroyed. The original client properly frees connection_strings in ValkeyClient.deinit().

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.zig : In Zig code, be careful with allocators and use defer for cleanup

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to **/js_*.zig : Implement proper memory management with reference counting using `ref()`/`deref()` in JavaScript bindings

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : Use `JSC.markBinding(src())` in finalize methods for debugging purposes before calling `deinit()`

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-10-24T10:43:09.398Z

Learnt from: fmguerreiro
Repo: oven-sh/bun PR: 23774
File: src/install/PackageManager/updatePackageJSONAndInstall.zig:548-548
Timestamp: 2025-10-24T10:43:09.398Z
Learning: In Bun's Zig codebase, the `as(usize, intCast(...))` cast pattern triggers a Zig compiler bug that causes compilation to hang indefinitely when used in complex control flow contexts (loops + short-circuit operators + optional unwrapping). Avoid this pattern and use simpler alternatives like just `intCast(...)` if type casting is necessary.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : For reference-counted objects, use `.deref()` in finalize instead of `destroy()` to release references to other JS objects

Applied to files:

src/shell/TraceInterpreter.zig

🪛 GitHub Check: Lint JavaScript

src/js/builtins/shell.ts

[failure] 5-5: eslint(no-unused-vars)
Interface 'ShellTraceFlags' is declared but never used.

🔇 Additional comments (11)

test/js/bun/shell/trace.test.ts (3)
1-27: LGTM! Permission constants mirror the Zig implementation.

The Permission flags are correctly defined to match the Zig constants in TraceInterpreter.zig. The convenience combinations (READ, WRITE, CREATE, etc.) provide a clean API for test assertions.

28-48: LGTM! Basic structure tests are well-formed.

These tests correctly verify the trace result object structure and the echo builtin behavior.

338-353: Verify subshell cwd isolation test on Windows.

This test verifies cwd behavior with /tmp, which is Unix-specific. The assertion expect(readOps[1].cwd).not.toBe("/tmp") may not be meaningful on Windows.

Consider adding a platform guard or using a portable path:
-  test("traces subshell with cwd isolation", () => {
-    const result = $.trace`(cd /tmp && ls) && ls`;
+  test.skipIf(isWindows)("traces subshell with cwd isolation", () => {
+    const result = $.trace`(cd /tmp && ls) && ls`;
src/js/builtins/shell.ts (4)

32-56: LGTM! Trace operation and result interfaces are well-defined.

The ShellTraceOperation and ShellTraceResult interfaces correctly model the data returned from the Zig tracing layer.

58-68: LGTM! Template function signature updated correctly.

The traceShellScript_ parameter is properly added and typed to return ShellTraceResult.

409-423: LGTM! Trace function implementation follows the BunShell pattern.

The trace function correctly:

Validates tagged template usage

Sets cwd before env (matching the comment about PWD injection)

Returns the trace result from the Zig layer

438-441: LGTM! Trace property correctly exposed on BunShell.

The trace function is properly exposed as an enumerable property on BunShell.

src/shell/TraceInterpreter.zig (4)

1-35: LGTM! Permission flags correctly mirror Unix constants.

The octal permission values properly align with standard Unix open(2) and access(2) flags, with extended flags using higher bits to avoid conflicts.

54-110: LGTM! EnvSnapshot properly manages memory.

The clone and deinit methods correctly handle memory ownership for duplicated keys and values.

131-140: LGTM! TracedOperation.deinit properly frees all owned resources.

The deinit correctly frees path, command, cwd, env snapshot, and args array with proper iteration.

1231-1257: LGTM! Public trace function is well-structured.

The function properly initializes the result and context, runs the trace, and returns the result. The defer on ctx.deinit() correctly cleans up resources while preserving the result.

…pansion - Remove unused expandDoubleQuoted function - Use WTF8 lexer for non-ASCII brace patterns (matching Expansion.zig behavior) 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

Jarred-Sumner · 2025-12-24T04:32:20Z

+    /// Exported environment (for subprocess)
+    export_env: EnvMap,
+    /// Accumulated traced environment variables (snapshot for each operation)
+    traced_env: std.StringHashMapUnmanaged([]const u8),


Use bun.StringHashMap

Jarred-Sumner · 2025-12-24T04:35:23Z

+    allocator: Allocator,
+    result: *TraceResult,
+    /// Current working directory during trace
+    cwd: std.array_list.Managed(u8),


Use an unmanaged arraylist there is no need to store the allocator here.

Jarred-Sumner · 2025-12-24T04:35:36Z

+    /// Whether the current operation has dynamic (non-statically-analyzable) values
+    current_dynamic: bool,
+    /// JS objects from template
+    jsobjs: []JSValue,


Why are we keeping the JSValues as an array?

Jarred-Sumner · 2025-12-24T04:36:09Z

+/// TraceContext holds state during trace interpretation
+pub const TraceContext = struct {
+    allocator: Allocator,
+    result: *TraceResult,


Why is this a pointer?

Jarred-Sumner · 2025-12-24T04:36:22Z

+
+/// TraceContext holds state during trace interpretation
+pub const TraceContext = struct {
+    allocator: Allocator,


Why is this allocator stored?

Jarred-Sumner · 2025-12-24T04:37:02Z

+            this.cwd.clearRetainingCapacity();
+            bun.handleOom(this.cwd.appendSlice(new_cwd));
+        } else {
+            bun.handleOom(this.cwd.append('/'));


This path normalziation is completely wrong for Windows.

@TagName

- Extract expandBracesAlloc to braces.zig as shared helper - Simplify Stream.toJS using @TagName - Use bun.StringHashMapUnmanaged instead of std.StringHashMapUnmanaged - Replace catch bun.outOfMemory() with bun.handleOom() - Replace .jsBoolean(true) with .true - Replace arguments_old with argumentsAsArray - Remove duplicate ShellTraceFlags interface from shell.ts 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

coderabbitai

Actionable comments posted: 6

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📥 Commits

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📒 Files selected for processing (5)

src/js/builtins/shell.ts
src/shell/TraceInterpreter.zig
src/shell/braces.zig
src/shell/shell.zig
test/js/bun/shell/trace.test.ts

🧰 Additional context used

📓 Path-based instructions (9)

src/**/*.{cpp,zig}

📄 CodeRabbit inference engine (.cursor/rules/building-bun.mdc)

src/**/*.{cpp,zig}: Use bun bd or bun run build:debug to build debug versions for C++ and Zig source files; creates debug build at ./build/debug/bun-debug
Run tests using bun bd test <test-file> with the debug build; never use bun test directly as it will not include your changes
Execute files using bun bd <file> <...args>; never use bun <file> directly as it will not include your changes
Enable debug logs for specific scopes using BUN_DEBUG_$(SCOPE)=1 environment variable
Code generation happens automatically as part of the build process; no manual code generation commands are required

Files:

src/shell/braces.zig
src/shell/TraceInterpreter.zig
src/shell/shell.zig

src/**/*.zig

📄 CodeRabbit inference engine (.cursor/rules/building-bun.mdc)

Use bun.Output.scoped(.${SCOPE}, .hidden) for creating debug logs in Zig code

Implement core functionality in Zig, typically in its own directory in src/

src/**/*.zig: Private fields in Zig are fully supported using the # prefix: struct { #foo: u32 };
Use decl literals in Zig for declaration initialization: const decl: Decl = .{ .binding = 0, .value = 0 };
Prefer @import at the bottom of the file (auto formatter will move them automatically)

Files:

src/shell/braces.zig
src/shell/TraceInterpreter.zig
src/shell/shell.zig

**/*.zig

📄 CodeRabbit inference engine (.cursor/rules/zig-javascriptcore-classes.mdc)

**/*.zig: Expose generated bindings in Zig structs using pub const js = JSC.Codegen.JS<ClassName> with trait conversion methods: toJS, fromJS, and fromJSDirect
Use consistent parameter name globalObject instead of ctx in Zig constructor and method implementations
Use bun.JSError!JSValue return type for Zig methods and constructors to enable proper error handling and exception propagation
Implement resource cleanup using deinit() method that releases resources, followed by finalize() called by the GC that invokes deinit() and frees the pointer
Use JSC.markBinding(@src()) in finalize methods for debugging purposes before calling deinit()
For methods returning cached properties in Zig, declare external C++ functions using extern fn and callconv(JSC.conv) calling convention
Implement getter functions with naming pattern get<PropertyName> in Zig that accept this and globalObject parameters and return JSC.JSValue
Access JavaScript CallFrame arguments using callFrame.argument(i), check argument count with callFrame.argumentCount(), and get this with callFrame.thisValue()
For reference-counted objects, use .deref() in finalize instead of destroy() to release references to other JS objects

In Zig code, be careful with allocators and use defer for cleanup

Files:

src/shell/braces.zig
src/shell/TraceInterpreter.zig
src/shell/shell.zig

test/**/*.{js,ts,jsx,tsx}

📄 CodeRabbit inference engine (.cursor/rules/writing-tests.mdc)

test/**/*.{js,ts,jsx,tsx}: Write tests as JavaScript and TypeScript files using Jest-style APIs (test, describe, expect) and import from bun:test
Use test.each and data-driven tests to reduce boilerplate when testing multiple similar cases

Files:

test/js/bun/shell/trace.test.ts

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}

📄 CodeRabbit inference engine (test/CLAUDE.md)

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}: Use bun:test with files that end in *.test.{ts,js,jsx,tsx,mjs,cjs}
Do not write flaky tests. Never wait for time to pass in tests; always wait for the condition to be met instead of using an arbitrary amount of time
Never use hardcoded port numbers in tests. Always use port: 0 to get a random port
Prefer concurrent tests over sequential tests using test.concurrent or describe.concurrent when multiple tests spawn processes or write files, unless it's very difficult to make them concurrent
When spawning Bun processes in tests, use bunExe and bunEnv from harness to ensure the same build of Bun is used and debug logging is silenced
Use -e flag for single-file tests when spawning Bun processes
Use tempDir() from harness to create temporary directories with files for multi-file tests instead of creating files manually
Prefer async/await over callbacks in tests
When callbacks must be used and it's just a single callback, use Promise.withResolvers to create a promise that can be resolved or rejected from a callback
Do not set a timeout on tests. Bun already has timeouts
Use Buffer.alloc(count, fill).toString() instead of 'A'.repeat(count) to create repetitive strings in tests, as ''.repeat is very slow in debug JavaScriptCore builds
Use describe blocks for grouping related tests
Always use await using or using to ensure proper resource cleanup in tests for APIs like Bun.listen, Bun.connect, Bun.spawn, Bun.serve, etc
Always check exit codes and test error scenarios in error tests
Use describe.each() for parameterized tests
Use toMatchSnapshot() for snapshot testing
Use beforeAll(), afterEach(), beforeEach() for setup/teardown in tests
Track resources (servers, clients) in arrays for cleanup in afterEach()

Files:

test/js/bun/shell/trace.test.ts

**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

**/*.test.ts?(x): Never use bun test directly - always use bun bd test to run tests with debug build changes
For single-file tests, prefer -e flag over tempDir
For multi-file tests, prefer tempDir and Bun.spawn over single-file tests
Use normalizeBunSnapshot to normalize snapshot output of tests
Never write tests that check for 'panic', 'uncaught exception', or similar strings in test output
Use tempDir from harness to create temporary directories - do not use tmpdirSync or fs.mkdtempSync
When spawning processes in tests, expect stdout before expecting exit code for more useful error messages on test failure
Do not write flaky tests - do not use setTimeout in tests; instead await the condition to be met
Verify tests fail with USE_SYSTEM_BUN=1 bun test <file> and pass with bun bd test <file> - tests are invalid if they pass with USE_SYSTEM_BUN=1
Test files must end with .test.ts or .test.tsx
Avoid shell commands like find or grep in tests - use Bun's Glob and built-in tools instead

Files:

test/js/bun/shell/trace.test.ts

test/**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

Always use port: 0 in tests - do not hardcode ports or use custom random port number functions

Files:

test/js/bun/shell/trace.test.ts

src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js}

📄 CodeRabbit inference engine (src/js/CLAUDE.md)

src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js}: Use .$call() and .$apply() instead of .call() and .apply() to prevent user tampering with function invocation
Use string literal require() statements only; dynamic requires are not permitted
Export modules using export default { ... } syntax; modules are NOT ES modules
Use JSC intrinsics (prefixed with $) such as $Array.from(), $isCallable(), and $newArrayWithSize() for performance-critical operations
Use private globals and methods with $ prefix (e.g., $Array, map.$set()) instead of public JavaScript globals
Use $debug() for debug logging and $assert() for assertions; both are stripped in release builds
Validate function arguments using validators from internal/validators and throw $ERR_* error codes for invalid arguments
Use process.platform and process.arch for platform detection; these values are inlined and dead-code eliminated at build time

Files:

src/js/builtins/shell.ts

src/js/{builtins,node,bun,thirdparty,internal}/**/*.ts

📄 CodeRabbit inference engine (src/js/CLAUDE.md)

Builtin functions must include this parameter typing in TypeScript to enable direct method binding in C++

Files:

src/js/builtins/shell.ts

🧠 Learnings (54)

📓 Common learnings

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to src/bun.js/bindings/**/*.cpp : Cache structures in ZigGlobalObject for JavaScript class bindings

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Add tests for new Bun runtime functionality

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Write JS builtins for Bun's Node.js compatibility and APIs, and run `bun bd` after changes

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : Use `JSC.markBinding(src())` in finalize methods for debugging purposes before calling `deinit()`

📚 Learning: 2025-09-02T18:27:23.279Z

Learnt from: taylordotfish
Repo: oven-sh/bun PR: 22227
File: src/collections/multi_array_list.zig:24-24
Timestamp: 2025-09-02T18:27:23.279Z
Learning: The `#allocator` syntax in bun's custom Zig implementation is valid and does not require quoting with @"#allocator". Private fields using the `#` prefix work correctly throughout the codebase without special quoting syntax.

Applied to files:

src/shell/braces.zig
src/shell/TraceInterpreter.zig

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.zig : In Zig code, be careful with allocators and use defer for cleanup

Applied to files:

src/shell/braces.zig
src/shell/TraceInterpreter.zig

📚 Learning: 2025-09-02T17:07:29.377Z

Learnt from: taylordotfish
Repo: oven-sh/bun PR: 22227
File: src/allocators.zig:873-879
Timestamp: 2025-09-02T17:07:29.377Z
Learning: In Zig's bun codebase, in functions like `unpackNullable` that return `?Allocator`, anonymous method calls like `.get()` are preferred over fully qualified calls like `Nullable(Allocator).get(allocator)` because the compiler can infer the correct type from the return type context. This follows Zig's anonymous literal syntax conventions.

Applied to files:

src/shell/braces.zig
src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/test/v8/v8.test.ts : Add corresponding test cases to test/v8/v8.test.ts using checkSameOutput() function to compare Node.js and Bun output

Applied to files:

test/js/bun/shell/trace.test.ts
src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : When spawning Bun processes in tests, use `bunExe` and `bunEnv` from `harness` to ensure the same build of Bun is used and debug logging is silenced

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/dev/esm.test.ts : Organize ESM tests in esm.test.ts for tests about various ESM features in development mode

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Avoid shell commands like `find` or `grep` in tests - use Bun's Glob and built-in tools instead

Applied to files:

test/js/bun/shell/trace.test.ts
src/js/builtins/shell.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Verify tests fail with `USE_SYSTEM_BUN=1 bun test <file>` and pass with `bun bd test <file>` - tests are invalid if they pass with USE_SYSTEM_BUN=1

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Add tests for new Bun runtime functionality

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-19T02:44:46.354Z

Learnt from: theshadow27
Repo: oven-sh/bun PR: 23798
File: packages/bun-otel/context-propagation.test.ts:1-1
Timestamp: 2025-10-19T02:44:46.354Z
Learning: In the Bun repository, standalone packages under packages/ (e.g., bun-vscode, bun-inspector-protocol, bun-plugin-yaml, bun-plugin-svelte, bun-debug-adapter-protocol, bun-otel) co-locate their tests with package source code using *.test.ts files. This follows standard npm/monorepo patterns. The test/ directory hierarchy (test/js/bun/, test/cli/, test/js/node/) is reserved for testing Bun's core runtime APIs and built-in functionality, not standalone packages.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:50.422Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/writing-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:50.422Z
Learning: Applies to test/**/*.{js,ts,jsx,tsx} : Write tests as JavaScript and TypeScript files using Jest-style APIs (`test`, `describe`, `expect`) and import from `bun:test`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `-e` flag for single-file tests when spawning Bun processes

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Never use `bun test` directly - always use `bun bd test` to run tests with debug build changes

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `process.platform` and `process.arch` for platform detection; these values are inlined and dead-code eliminated at build time

Applied to files:

test/js/bun/shell/trace.test.ts
src/js/builtins/shell.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For multi-file tests, prefer `tempDir` and `Bun.spawn` over single-file tests

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For single-file tests, prefer `-e` flag over `tempDir`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/js/node/test/{parallel,sequential}/*.js : For test/js/node/test/{parallel,sequential}/*.js files without a .test extension, use `bun bd <file>` instead of `bun bd test <file>` since these expect exit code 0 and don't use bun's test runner

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-26T01:32:04.844Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 24082
File: test/cli/test/coverage.test.ts:60-112
Timestamp: 2025-10-26T01:32:04.844Z
Learning: In the Bun repository test files (test/cli/test/*.test.ts), when spawning Bun CLI commands with Bun.spawnSync for testing, prefer using stdio: ["inherit", "inherit", "inherit"] to inherit stdio streams rather than piping them.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:50.422Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/writing-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:50.422Z
Learning: Applies to test/cli/**/*.{js,ts,jsx,tsx} : When testing Bun as a CLI, use the `spawn` API from `bun` with the `bunExe()` and `bunEnv` from `harness` to execute Bun commands and validate exit codes, stdout, and stderr

Applied to files:

test/js/bun/shell/trace.test.ts
src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `tempDir()` from harness to create temporary directories with files for multi-file tests instead of creating files manually

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Use `tempDir` from `harness` to create temporary directories - do not use `tmpdirSync` or `fs.mkdtempSync`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:35:08.612Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/dev-server-tests.mdc:0-0
Timestamp: 2025-11-24T18:35:08.612Z
Learning: Applies to test/bake/**/*.test.ts : Use `dev.write()`, `dev.patch()`, and `dev.delete()` to mutate the filesystem instead of `node:fs` APIs, as dev server functions are hooked to wait for hot-reload and notify clients

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Always use `await using` or `using` to ensure proper resource cleanup in tests for APIs like Bun.listen, Bun.connect, Bun.spawn, Bun.serve, etc

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-09-12T18:16:50.754Z

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 22606
File: src/glob/GlobWalker.zig:449-452
Timestamp: 2025-09-12T18:16:50.754Z
Learning: For Bun codebase: prefer using `std.fs.path.sep` over manual platform separator detection, and use `bun.strings.lastIndexOfChar` instead of `std.mem.lastIndexOfScalar` for string operations.

Applied to files:

test/js/bun/shell/trace.test.ts
src/shell/TraceInterpreter.zig

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Use `normalizeBunSnapshot` to normalize snapshot output of tests

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `$debug()` for debug logging and `$assert()` for assertions; both are stripped in release builds

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-14T16:07:01.064Z

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 24719
File: docs/bundler/executables.mdx:527-560
Timestamp: 2025-11-14T16:07:01.064Z
Learning: In the Bun repository, certain bundler features like compile with code splitting (--compile --splitting) are CLI-only and not supported in the Bun.build() JavaScript API. Tests for CLI-only features use backend: "cli" flag (e.g., test/bundler/bundler_compile_splitting.test.ts). The CompileBuildConfig interface correctly restricts these with splitting?: never;. When documenting CLI-only bundler features, add a note clarifying they're not available via the programmatic API.

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use JSC intrinsics (prefixed with `$`) such as `$Array.from()`, `$isCallable()`, and `$newArrayWithSize()` for performance-critical operations

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.ts : Builtin functions must include `this` parameter typing in TypeScript to enable direct method binding in C++

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `.$call()` and `.$apply()` instead of `.call()` and `.apply()` to prevent user tampering with function invocation

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Write JS builtins for Bun's Node.js compatibility and APIs, and run `bun bd` after changes

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use private globals and methods with `$` prefix (e.g., `$Array`, `map.$set()`) instead of public JavaScript globals

Applied to files:

src/js/builtins/shell.ts

📚 Learning: 2025-10-14T04:04:47.894Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23636
File: src/shell/ParsedShellScript.zig:15-0
Timestamp: 2025-10-14T04:04:47.894Z
Learning: In src/shell/ParsedShellScript.zig, the JavaScript garbage collector's memory reporting API only allows reporting extra memory allocation once at object creation time. Therefore, `estimated_size_for_gc` is intentionally set once during initialization (via `#computeEstimatedSizeForGC()`) and not updated afterward, even though fields like `args`, `export_env`, and `cwd` may be mutated by methods like `setCwd()`, `setEnv()`, and `take()`. The `estimatedSize()` method returns this cached initial value, while `memoryCost()` computes the size on-demand.

Applied to files:

src/js/builtins/shell.ts
src/shell/TraceInterpreter.zig

📚 Learning: 2025-10-08T13:56:00.875Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23373
File: src/bun.js/api/BunObject.zig:2514-2521
Timestamp: 2025-10-08T13:56:00.875Z
Learning: For Bun codebase: prefer using `bun.path` utilities (e.g., `bun.path.joinAbsStringBuf`, `bun.path.join`) over `std.fs.path` functions for path operations.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-10-24T10:43:09.398Z

Learnt from: fmguerreiro
Repo: oven-sh/bun PR: 23774
File: src/install/PackageManager/updatePackageJSONAndInstall.zig:548-548
Timestamp: 2025-10-24T10:43:09.398Z
Learning: In Bun's Zig codebase, the `as(usize, intCast(...))` cast pattern triggers a Zig compiler bug that causes compilation to hang indefinitely when used in complex control flow contexts (loops + short-circuit operators + optional unwrapping). Avoid this pattern and use simpler alternatives like just `intCast(...)` if type casting is necessary.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-09-05T18:45:29.200Z

Learnt from: markovejnovic
Repo: oven-sh/bun PR: 21728
File: src/valkey/js_valkey.zig:0-0
Timestamp: 2025-09-05T18:45:29.200Z
Learning: In JSValkeyClient.cloneWithoutConnecting() in src/valkey/js_valkey.zig, the address/username/password fields must be repointed to the duplicated connection_strings buffer to avoid use-after-free when the original client is destroyed. The original client properly frees connection_strings in ValkeyClient.deinit().

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to **/js_*.zig : Implement proper memory management with reference counting using `ref()`/`deref()` in JavaScript bindings

Applied to files:

src/shell/TraceInterpreter.zig
src/shell/shell.zig

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : Use `JSC.markBinding(src())` in finalize methods for debugging purposes before calling `deinit()`

Applied to files:

src/shell/TraceInterpreter.zig
src/shell/shell.zig

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : For reference-counted objects, use `.deref()` in finalize instead of `destroy()` to release references to other JS objects

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to src/bun.js/bindings/**/*.cpp : Define properties using HashTableValue arrays in C++ JavaScript class bindings

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-10-21T20:57:01.892Z

Learnt from: taylordotfish
Repo: oven-sh/bun PR: 23889
File: src/string.zig:751-752
Timestamp: 2025-10-21T20:57:01.892Z
Learning: In Zig code handling bun.String: calling deref() on an empty bun.String (String.empty or after being set to .empty) is well-defined behavior and safely does nothing (no-op). While such calls may be redundant and could be removed for code clarity, their presence is not a correctness issue.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Reference existing modules like Valkey, S3Client, or SQLite as guides when implementing new Bun features

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-09-24T00:08:49.281Z

Learnt from: taylordotfish
Repo: oven-sh/bun PR: 22917
File: src/collections/array_list.zig:302-308
Timestamp: 2025-09-24T00:08:49.281Z
Learning: In Zig's ArrayListAlignedUnmanaged, the resize method when shrinking (new_len < old_len) does not free or move the underlying memory allocation - it only updates the items.len field to new_len. This means memory beyond the new length remains valid and accessible, making it safe to access self.items().ptr[new_len..old_len] after calling resize.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-03T20:43:06.996Z

Learnt from: pfgithub
Repo: oven-sh/bun PR: 24273
File: src/bun.js/test/snapshot.zig:19-19
Timestamp: 2025-11-03T20:43:06.996Z
Learning: In Bun's Zig codebase, when storing JSValue objects in collections like ArrayList, use `jsc.Strong.Optional` (not raw JSValue). When adding values, wrap them with `jsc.Strong.Optional.create(value, globalThis)`. In cleanup code, iterate the collection calling `.deinit()` on each Strong.Optional item before calling `.deinit()` on the ArrayList itself. This pattern automatically handles GC protection. See examples in src/bun.js/test/ScopeFunctions.zig and src/bun.js/node/node_cluster_binding.zig.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-19T05:15:22.823Z

Learnt from: pfgithub
Repo: oven-sh/bun PR: 23764
File: src/bun.js/test/timers/FakeTimers.zig:240-0
Timestamp: 2025-11-19T05:15:22.823Z
Learning: In Bun's Zig codebase, `CallFrame.argumentsAsArray(N)` always returns an array of exactly N elements. If fewer than N arguments were passed to the function, the missing slots are filled with `.undefined` JSValue. This means accessing `argumentsAsArray(N)[i]` where i < N is always safe and will never trap—it will simply return `.undefined` if that argument wasn't provided by the caller.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-09-05T19:49:26.188Z

Learnt from: markovejnovic
Repo: oven-sh/bun PR: 21728
File: src/valkey/js_valkey_functions.zig:852-867
Timestamp: 2025-09-05T19:49:26.188Z
Learning: In Bun’s Zig code, `.js_undefined` is a valid and preferred JSValue literal for “undefined” (e.g., resolving JSPromise). Do not refactor usages to `jsc.JSValue.jsUndefined()`, especially in src/valkey/js_valkey_functions.zig unsubscribe().

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Map V8's Local<T> handles to JSC's JSValue system using the handle scope system to manage memory lifetimes

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-09-03T05:09:24.272Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 22335
File: src/http.zig:1376-1393
Timestamp: 2025-09-03T05:09:24.272Z
Learning: In bun's HTTP module, `bun.http.default_allocator` is the correct allocator to use for internal HTTP buffers like MutableString initialization for response_message_buffer and compressed_body. This allocator is initialized in HTTPThread.zig as `bun.http.default_arena.allocator()` and is used consistently across the HTTP module, separate from any local `default_allocator` variables.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-11T22:55:04.070Z

Learnt from: pfgithub
Repo: oven-sh/bun PR: 24571
File: src/css/selectors/parser.zig:908-916
Timestamp: 2025-11-11T22:55:04.070Z
Learning: In oven-sh/bun, CSS serialization uses an arena allocator. In src/css/selectors/parser.zig, functions like PseudoClass.toCss and PseudoElement.toCss intentionally do not call deinit on std.Io.Writer.Allocating, scratch buffers, or css.Printer because dest.allocator is an arena and these temporaries are reclaimed when the CSS pass completes. Only debug-only paths (e.g., DeclarationBlock.DebugFmt in src/css/declaration.zig) may explicitly deinit.

Applied to files:

src/shell/TraceInterpreter.zig

📚 Learning: 2025-11-24T18:36:08.558Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/zig-javascriptcore-classes.mdc:0-0
Timestamp: 2025-11-24T18:36:08.558Z
Learning: Applies to **/*.zig : Expose generated bindings in Zig structs using `pub const js = JSC.Codegen.JS<ClassName>` with trait conversion methods: `toJS`, `fromJS`, and `fromJSDirect`

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-11-24T18:35:39.205Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: .cursor/rules/registering-bun-modules.mdc:0-0
Timestamp: 2025-11-24T18:35:39.205Z
Learning: Applies to src/**/*.zig : Implement core functionality in Zig, typically in its own directory in `src/`

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-10-14T04:04:17.132Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 23636
File: src/shell/interpreter.zig:672-0
Timestamp: 2025-10-14T04:04:17.132Z
Learning: In Bun's shell interpreter (src/shell/interpreter.zig), the JavaScript garbage collector's memory reporting API only allows reporting extra memory allocation once at object creation time. Therefore, `estimated_size_for_gc` is intentionally set once during initialization and not updated afterward, even though fields like `root_io`, `vm_args_utf8`, and `export_env` may be mutated later. The `estimatedSize()` method returns this cached initial value, while `memoryCost()` computes the size on-demand.

Applied to files:

src/shell/shell.zig

📚 Learning: 2025-09-02T17:14:46.924Z

Learnt from: taylordotfish
Repo: oven-sh/bun PR: 22227
File: src/safety/alloc.zig:93-95
Timestamp: 2025-09-02T17:14:46.924Z
Learning: In bun's Zig codebase, they use a custom extension of Zig that supports private field syntax with the `#` prefix (e.g., `#allocator`, `#trace`). This is not standard Zig syntax but is valid in their custom implementation. Fields prefixed with `#` are private fields that cannot be accessed from outside the defining struct.

Applied to files:

src/shell/shell.zig

🔇 Additional comments (18)

src/shell/shell.zig (1)

4-5: TraceInterpreter re-export looks correct and minimal

Publicly re-exporting TraceInterpreter from ./TraceInterpreter.zig alongside interpret/subproc cleanly exposes the new shell tracing module without extra surface area. No issues here.

test/js/bun/shell/trace.test.ts (2)

368-412: Brace/glob expansion tests look good and use harness tempDir correctly

The brace expansion and glob tests exercise exactly the behaviors the new trace API is meant to expose (multiple READ ops for expanded paths, correct path shapes) and now rely on tempDir plus using for isolation/cleanup instead of writing into /tmp. The expectations are precise but not brittle, and the path.join comparison handles platform separators.

No changes needed here.

379-393: Tilde-expansion expectations are now reasonably cross-platform

The tilde test no longer assumes a Unix-only layout: it just checks that ~ is resolved and that the tail of the path matches .config/test.txt, with a Windows-aware regex for separators. That’s an appropriate level of specificity for a cross-platform trace API.

Looks good.

src/js/builtins/shell.ts (3)

6-30: ShellTraceOperation/Result typing is clear and matches the described API surface

The ShellTraceOperation / ShellTraceResult interfaces accurately capture what tests and the Zig binding promise (flags, cwd, path/command/args/env/stream, plus a dynamic marker). Keeping these as TS-only types avoids runtime overhead while giving good editor/TS support for users of $.trace.

No issues here.

383-397: trace implementation correctly mirrors $ behavior without executing commands

The new trace(first, ...rest):

Enforces tagged-template usage (good DX).

Builds a ParsedShellScript via createParsedShellScript(first.raw, rest).

Applies BunShell’s current cwd and env (so $.cwd() / $.env() settings are respected).

Delegates to the Zig traceShellScript binding and returns its ShellTraceResult directly.

Exposing it as BunShell.trace makes $.trace\...`available without affecting existing$`` behavior. This is a clean, minimal addition.

Also applies to: 412-415

32-43: Verify that all call sites of createBunShellTemplateFunction pass the third argument traceShellScript_

The factory function correctly accepts and uses the traceShellScript_ parameter (typed and invoked at line 396 in the trace function). However, call sites cannot be located in the src/js directory, which suggests they are in C++ bindings or generated code outside the visible codebase. Ensure backward compatibility is maintained when initializing this factory across all build configurations.

src/shell/TraceInterpreter.zig (12)

8-47: LGTM: Permission flags and Stream enum are well-defined.

The Unix-style permission flags and Stream enum follow standard conventions and correctly convert to JavaScript values.

107-209: LGTM: TracedOperation structure with proper memory management.

The struct correctly manages ownership of all allocated fields and properly converts to JavaScript with error handling.

356-377: Logic is correct but depends on StringHashMap refactoring.

The environment variable update logic correctly handles both new insertions and updates to existing keys. However, once traced_env is refactored to use bun.StringHashMap (managed version), the API calls will change slightly (e.g., put(this.allocator, ...) becomes put(...)).

493-615: LGTM: AST traversal logic is well-structured.

The recursive traversal properly handles all shell constructs (commands, pipelines, subshells, conditionals, assignments) with correct memory management using defer for temporary allocations.

715-851: LGTM: Comprehensive builtin command handling.

The builtin tracing correctly models file operations for each command type. The multi-file support for mv and cp properly handles both two-argument and N-argument forms.

853-900: LGTM: External command tracing with proper cleanup.

The function correctly resolves the command path, collects arguments, and records execution with redirections. Arguments are properly freed after being duplicated in addOperationWithArgs.

902-943: LGTM: Redirection info extraction is correct.

The function properly handles all redirection cases including combined stdout/stderr redirections, with correct path duplication where needed.

949-1158: LGTM: Expansion logic with proper glob and brace handling.

The expansion functions correctly handle:

Brace expansion via the shared Braces helper

Glob patterns using GlobWalker with proper arena cleanup

Dynamic value tracking for command substitutions and variable arguments

Tilde expansion to HOME directory

Memory management is sound with proper use of defer and path duplication.

1165-1231: LGTM: Public API with corrected lifetime management.

The trace() and traceShellScript() functions properly manage the lifecycle of all resources. The cwd_utf8 slice lifetime issue noted in previous reviews has been correctly addressed with the deferred cleanup pattern.

294-341: The design concerns in this review are based on outdated observations or incorrect analysis. The code has already addressed most of them:

Allocator storage is necessary: Used extensively across deinit(), setTracedEnv(), snapshotEnv(), resolvePath(), and addOperationFull(). The comment correctly explains it's needed "throughout traversal for allocating strings, paths, etc." Passing it to every method signature would be more verbose than storing it.

Result pointer is justified: The comment correctly states it's "created before the context and operations are added to it during traversal." The structure needs to accumulate traced operations during traversal, making this design appropriate.

JSValues array is already documented: The field comment clearly states: "JS objects from template literal interpolation, indexed by position." The purpose and usage context are explained.

StringHashMapUnmanaged comparison is incorrect: The review suggests using managed StringHashMap like EnvSnapshot, but EnvSnapshot.vars also uses bun.StringHashMapUnmanaged([]const u8). Both use the unmanaged variant consistently, so the recommendation is based on a false premise.

The code demonstrates clear ownership patterns (e.g., export_env with owns_export_env flag). The design choices are reasonable given the usage patterns throughout the implementation.

49-105: The review comment is incorrect. While the codebase does demonstrate a consistent preference for bun.StringHashMap (managed) over bun.StringHashMapUnmanaged, the review's justification—citing "Jarred-Sumner's comment"—is unfounded. No such maintainer feedback exists in the code, git history, or file comments.

Additionally, the current implementation using bun.StringHashMapUnmanaged is correct and properly implemented. Both EnvSnapshot.deinit() and TraceContext.deinit() correctly iterate over entries to free keys and values, then call deinit(allocator) on the unmanaged map, following established Zig patterns for allocator management.

If a change to managed StringHashMap is desired, it should be justified by codebase consistency rather than non-existent maintainer feedback.

Likely an incorrect or invalid review comment.

473-486: The code is already using bun.path utilities—ResolvePath is an alias for bun.path (line 1237). The implementation correctly uses Platform.auto, which compiles to .windows or .posix at compile time based on the target OS, ensuring platform-appropriate path semantics. No maintainer feedback exists indicating Windows path handling issues in this code. No changes required.

Likely an incorrect or invalid review comment.

coderabbitai · 2025-12-25T06:39:11Z

+/// High-level helper that expands brace patterns in a string.
+/// Returns a list of expanded strings. Caller owns the returned memory.
+/// On error or if no expansion is needed, returns the input as a single-element list.
+pub fn expandBracesAlloc(input: []const u8, allocator: Allocator) std.ArrayListUnmanaged([]const u8) {
+    var out: std.ArrayListUnmanaged([]const u8) = .{};
+
+    // Use arena for temporary tokenization
+    var arena = std.heap.ArenaAllocator.init(allocator);
+    defer arena.deinit();
+    const arena_alloc = arena.allocator();
+
+    // Tokenize - use appropriate lexer based on content
+    const lexer_output = if (bun.strings.isAllASCII(input))
+        Lexer.tokenize(arena_alloc, input) catch {
+            out.append(allocator, allocator.dupe(u8, input) catch return out) catch {};
+            return out;
+        }
+    else
+        NewLexer(.wtf8).tokenize(arena_alloc, input) catch {
+            out.append(allocator, allocator.dupe(u8, input) catch return out) catch {};
+            return out;
+        };
+
+    const expansion_count = calculateExpandedAmount(lexer_output.tokens.items[0..]);
+    if (expansion_count == 0) {
+        out.append(allocator, allocator.dupe(u8, input) catch return out) catch {};
+        return out;
+    }
+
+    // Allocate expanded strings
+    const expanded_strings = arena_alloc.alloc(std.array_list.Managed(u8), expansion_count) catch {
+        out.append(allocator, allocator.dupe(u8, input) catch return out) catch {};
+        return out;
+    };
+
+    for (0..expansion_count) |i| {
+        expanded_strings[i] = std.array_list.Managed(u8).init(allocator);
+    }
+
+    // Perform brace expansion
+    expand(
+        arena_alloc,
+        lexer_output.tokens.items[0..],
+        expanded_strings,
+        lexer_output.contains_nested,
+    ) catch {
+        for (expanded_strings) |*s| s.deinit();
+        out.append(allocator, allocator.dupe(u8, input) catch return out) catch {};
+        return out;
+    };
+
+    // Collect results
+    for (expanded_strings) |*s| {
+        const slice = s.toOwnedSlice() catch "";
+        if (slice.len > 0) {
+            out.append(allocator, slice) catch {};
+        }
+    }
+
+    return out;
+}


⚠️ Potential issue | 🔴 Critical

🧩 Analysis chain

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#!/bin/bash # First, let's look at the file structure and locate the key functions wc -l src/shell/braces.zig head -50 src/shell/braces.zig | cat -n

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# Search for out_key_counter usage in the file rg -n "out_key_counter" src/shell/braces.zig

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# Look at where 'out' is indexed with new_key or out_key rg -n "out\[" src/shell/braces.zig | head -30

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# Look for any test files related to brace expansion fd -t f "brace.*test|test.*brace" --search-path test/

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# Look at the full expandBracesAlloc function context to verify the pre-allocation sed -n '726,801p' src/shell/braces.zig | cat -n

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# Look at the brace test file to see what cases are tested head -100 test/js/bun/shell/brace.test.ts | cat -n

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# Search for any existing assertions or bounds checks on out_key before indexing rg -B5 -A5 "out\[new_key\]|out\[out_key\]" src/shell/braces.zig | head -50

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# Check if calculateExpandedAmount and expand have matching logic for counting/creating variants # Let's trace through a simple example like "{a,b}{c,d}" # This should give 4 variants (ac, ad, bc, bd) cat > /tmp/test_expand.zig << 'EOF' // Quick test: for "{a,b}{c,d}", calculateExpandedAmount should return 4 // expand should create exactly 4 output strings // Let's verify the logic: // calculateExpandedAmount: // First {a,b}: 1 comma -> 2 variants // Second {c,d}: 1 comma -> 2 variants // At close of first: variant_count = 2 // At close of second: variant_count = 2 * 2 = 4 // expand with expandFlat: // out_key_counter starts at 1 // For first { with 2 variants: // i=0: use out_key (0) // i=1: new_key = 1, increment counter to 2 // After expanding first: out has 2 strings // For second { on each variant (key 0 and 1), with 2 variants each: // From key 0: i=0 use key 0, i=1 new_key=2, counter->3 // From key 1: i=0 use key 1, i=1 new_key=3, counter->4 // Final: out should have indices 0,1,2,3 = 4 strings // expansion_count = 4, so out is allocated with 4 elements // new_key values: 0,1,2,3 all < 4 ✓ EOF cat /tmp/test_expand.zig

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# Check if there's any protection against u16 overflow in expand ast-grep --pattern $'fn expand($_, $_, out: [], $_) { $$$ var out_key_counter: u16 = $_; $$$ out[new_key] $$$ }'

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# Verify type flow: expansion_count is u32, but out_key_counter is u16 # This is the critical issue - when expansion_count > u16::MAX, we have a mismatch python3 << 'EOF' # Trace the types: # calculateExpandedAmount returns u32 # expansion_count: u32 (line 729) # expanded_strings allocated with expansion_count elements (line 28) # expand() receives expanded_strings as out: []std.array_list.Managed(u8) # out_key_counter: u16 = 1 (line 62 in expand) # new_key = out_key_counter.* which is u16 # out[new_key] - indexing with u16 into a slice that could have more than 65535 elements print("CRITICAL TYPE MISMATCH FOUND:") print("- expansion_count: u32 (can be > 65535)") print("- out_key_counter: u16 (max 65535)") print("- If expansion_count > u16::MAX, then out[] is allocated larger than u16 can index") print("- out[new_key] will have undefined behavior when new_key wraps around") EOF

Repository: oven-sh/bun

Length of output: 141

Critical type safety bug: expansion_count (u32) exceeds out_key_counter indexing capacity (u16)

calculateExpandedAmount() returns u32, allowing expansion_count to exceed 65,535 variants. However, expand() uses out_key_counter as a u16 to index into the out[] array. If brace expansion produces more than 65,535 variants, the allocated array will have more elements than a u16 can address, causing out[new_key] to index out of bounds when the counter wraps or is exhausted. This is a memory safety vulnerability, not just a counting mismatch.

Validate expansion_count <= 65535 in expandBracesAlloc() before allocation, or change out_key_counter and its use throughout expand(), expandNested(), and expandFlat() to u32 to match the potential allocation size. The file comment (line 3–4) documents "around 32k variants" but provides no runtime enforcement.

coderabbitai · 2025-12-25T06:39:11Z

+/// Result of tracing a shell script
+pub const TraceResult = struct {
+    /// All traced operations
+    operations: std.array_list.Managed(TracedOperation),
+    /// The working directory
+    cwd: []const u8,
+    /// Whether tracing was successful
+    success: bool,
+    /// Error message if tracing failed
+    error_message: ?[]const u8,
+    /// Allocator used for this result
+    allocator: Allocator,
+
+    pub fn init(allocator: Allocator, cwd: []const u8) TraceResult {
+        return .{
+            .operations = std.array_list.Managed(TracedOperation).init(allocator),
+            .cwd = bun.handleOom(allocator.dupe(u8, cwd)),
+            .success = true,
+            .error_message = null,
+            .allocator = allocator,
+        };
+    }
+
+    pub fn deinit(this: *TraceResult) void {
+        for (this.operations.items) |*op| {
+            op.deinit(this.allocator);
+        }
+        this.operations.deinit();
+        this.allocator.free(this.cwd);
+        if (this.error_message) |msg| {
+            this.allocator.free(msg);
+        }
+    }
+
+    pub fn addOperation(this: *TraceResult, op: TracedOperation) void {
+        bun.handleOom(this.operations.append(op));
+    }
+
+    pub fn setError(this: *TraceResult, msg: []const u8) void {
+        this.success = false;
+        this.error_message = bun.handleOom(this.allocator.dupe(u8, msg));
+    }
+
+    pub fn toJS(this: *const TraceResult, globalThis: *JSGlobalObject) bun.JSError!JSValue {
+        var result_obj = jsc.JSValue.createEmptyObject(globalThis, 4);
+
+        // Create operations array
+        const ops_array = try jsc.JSValue.createEmptyArray(globalThis, this.operations.items.len);
+        for (this.operations.items, 0..) |*op, i| {
+            const op_js = try op.toJS(globalThis);
+            try ops_array.putIndex(globalThis, @intCast(i), op_js);
+        }
+        result_obj.put(globalThis, bun.String.static("operations"), ops_array);
+
+        // Add cwd
+        result_obj.put(
+            globalThis,
+            bun.String.static("cwd"),
+            bun.String.init(this.cwd).toJS(globalThis),
+        );
+
+        // Add success
+        result_obj.put(
+            globalThis,
+            bun.String.static("success"),
+            jsc.JSValue.jsBoolean(this.success),
+        );
+
+        // Add error if present
+        if (this.error_message) |msg| {
+            result_obj.put(
+                globalThis,
+                bun.String.static("error"),
+                bun.String.init(msg).toJS(globalThis),
+            );
+        } else {
+            result_obj.put(globalThis, bun.String.static("error"), .null);
+        }
+
+        return result_obj;
+    }
+};


⚠️ Potential issue | 🟠 Major

Address maintainer feedback: Use unmanaged ArrayList.

Per Jarred-Sumner's comment, prefer std.ArrayListUnmanaged(TracedOperation) instead of the managed version to avoid storing the allocator in the struct.

Based on learnings, storing allocators is questionable when they can be passed as parameters to methods that need them.

🔎 Refactor to use unmanaged ArrayList

pub const TraceResult = struct { /// All traced operations - operations: std.array_list.Managed(TracedOperation), + operations: std.ArrayListUnmanaged(TracedOperation), /// The working directory cwd: []const u8, /// Whether tracing was successful success: bool, /// Error message if tracing failed error_message: ?[]const u8, /// Allocator used for this result allocator: Allocator, pub fn init(allocator: Allocator, cwd: []const u8) TraceResult { return .{ - .operations = std.array_list.Managed(TracedOperation).init(allocator), + .operations = .{}, .cwd = bun.handleOom(allocator.dupe(u8, cwd)), .success = true, .error_message = null, .allocator = allocator, }; } pub fn deinit(this: *TraceResult) void { for (this.operations.items) |*op| { op.deinit(this.allocator); } - this.operations.deinit(); + this.operations.deinit(this.allocator); // ... rest } pub fn addOperation(this: *TraceResult, op: TracedOperation) void { - bun.handleOom(this.operations.append(op)); + bun.handleOom(this.operations.append(this.allocator, op)); }

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

/// Result of tracing a shell script

pub const TraceResult = struct {

/// All traced operations

operations: std.array_list.Managed(TracedOperation),

/// The working directory

cwd: []const u8,

/// Whether tracing was successful

success: bool,

/// Error message if tracing failed

error_message: ?[]const u8,

/// Allocator used for this result

allocator: Allocator,

pub fn init(allocator: Allocator, cwd: []const u8) TraceResult {

return .{

.operations = std.array_list.Managed(TracedOperation).init(allocator),

.cwd = bun.handleOom(allocator.dupe(u8, cwd)),

.success = true,

.error_message = null,

.allocator = allocator,

};

}

pub fn deinit(this: *TraceResult) void {

for (this.operations.items) |*op| {

op.deinit(this.allocator);

}

this.operations.deinit();

this.allocator.free(this.cwd);

if (this.error_message) |msg| {

this.allocator.free(msg);

}

}

pub fn addOperation(this: *TraceResult, op: TracedOperation) void {

bun.handleOom(this.operations.append(op));

}

pub fn setError(this: *TraceResult, msg: []const u8) void {

this.success = false;

this.error_message = bun.handleOom(this.allocator.dupe(u8, msg));

}

pub fn toJS(this: *const TraceResult, globalThis: *JSGlobalObject) bun.JSError!JSValue {

var result_obj = jsc.JSValue.createEmptyObject(globalThis, 4);

// Create operations array

const ops_array = try jsc.JSValue.createEmptyArray(globalThis, this.operations.items.len);

for (this.operations.items, 0..) |*op, i| {

const op_js = try op.toJS(globalThis);

try ops_array.putIndex(globalThis, @intCast(i), op_js);

}

result_obj.put(globalThis, bun.String.static("operations"), ops_array);

// Add cwd

result_obj.put(

globalThis,

bun.String.static("cwd"),

bun.String.init(this.cwd).toJS(globalThis),

);

// Add success

result_obj.put(

globalThis,

bun.String.static("success"),

jsc.JSValue.jsBoolean(this.success),

);

// Add error if present

if (this.error_message) |msg| {

result_obj.put(

globalThis,

bun.String.static("error"),

bun.String.init(msg).toJS(globalThis),

);

} else {

result_obj.put(globalThis, bun.String.static("error"), .null);

}

return result_obj;

}

};

/// Result of tracing a shell script

pub const TraceResult = struct {

/// All traced operations

operations: std.ArrayListUnmanaged(TracedOperation),

/// The working directory

cwd: []const u8,

/// Whether tracing was successful

success: bool,

/// Error message if tracing failed

error_message: ?[]const u8,

/// Allocator used for this result

allocator: Allocator,

pub fn init(allocator: Allocator, cwd: []const u8) TraceResult {

return .{

.operations = .{},

.cwd = bun.handleOom(allocator.dupe(u8, cwd)),

.success = true,

.error_message = null,

.allocator = allocator,

};

}

pub fn deinit(this: *TraceResult) void {

for (this.operations.items) |*op| {

op.deinit(this.allocator);

}

this.operations.deinit(this.allocator);

this.allocator.free(this.cwd);

if (this.error_message) |msg| {

this.allocator.free(msg);

}

}

pub fn addOperation(this: *TraceResult, op: TracedOperation) void {

bun.handleOom(this.operations.append(this.allocator, op));

}

pub fn setError(this: *TraceResult, msg: []const u8) void {

this.success = false;

this.error_message = bun.handleOom(this.allocator.dupe(u8, msg));

}

pub fn toJS(this: *const TraceResult, globalThis: *JSGlobalObject) bun.JSError!JSValue {

var result_obj = jsc.JSValue.createEmptyObject(globalThis, 4);

// Create operations array

const ops_array = try jsc.JSValue.createEmptyArray(globalThis, this.operations.items.len);

for (this.operations.items, 0..) |*op, i| {

const op_js = try op.toJS(globalThis);

try ops_array.putIndex(globalThis, @intCast(i), op_js);

}

result_obj.put(globalThis, bun.String.static("operations"), ops_array);

// Add cwd

result_obj.put(

globalThis,

bun.String.static("cwd"),

bun.String.init(this.cwd).toJS(globalThis),

);

// Add success

result_obj.put(

globalThis,

bun.String.static("success"),

jsc.JSValue.jsBoolean(this.success),

);

// Add error if present

if (this.error_message) |msg| {

result_obj.put(

globalThis,

bun.String.static("error"),

bun.String.init(msg).toJS(globalThis),

);

} else {

result_obj.put(globalThis, bun.String.static("error"), .null);

}

return result_obj;

}

};

🤖 Prompt for AI Agents

In src/shell/TraceInterpreter.zig around lines 211-292, change TraceResult.operations from std.array_list.Managed(TracedOperation) to std.ArrayListUnmanaged(TracedOperation), remove the allocator field from the struct, and stop storing the allocator in init; update init to call .init() on the unmanaged list and keep duplicating cwd with the incoming allocator but do not save it. Change any methods that relied on this.allocator to instead take an Allocator parameter: deinit(this: *TraceResult, allocator: Allocator), addOperation(this: *TraceResult, allocator: Allocator, op: TracedOperation) (call operations.append(allocator, op)), and setError(this: *TraceResult, allocator: Allocator, msg: []const u8) (dup msg with the passed allocator). Also update toJS to not use a stored allocator (it shouldn’t need one) and update all call sites to pass the allocator where required; ensure deinit frees cwd and error_message using the allocator parameter and calls operations.deinit() (no stored allocator).

coderabbitai · 2025-12-25T06:39:11Z

+    pub fn resolvePath(this: *TraceContext, path: []const u8) []const u8 {
+        if (ResolvePath.Platform.auto.isAbsolute(path)) {
+            return bun.handleOom(this.allocator.dupe(u8, path));
+        }
+        // Join with cwd
+        const parts: []const []const u8 = &.{ this.cwdSlice(), path };
+        const joined = ResolvePath.joinZ(parts, .auto);
+        return bun.handleOom(this.allocator.dupe(u8, joined[0..joined.len]));
+    }


⚠️ Potential issue | 🔴 Critical

Windows path handling issue in resolvePath.

Similar to changeCwd, this method uses ResolvePath.Platform.auto and ResolvePath.joinZ, which the maintainer indicated are incorrect for Windows.

Use bun.path utilities for proper cross-platform path resolution. Based on learnings, these utilities handle Windows paths correctly.

🤖 Prompt for AI Agents

In src/shell/TraceInterpreter.zig around lines 402 to 410, resolvePath currently uses ResolvePath.Platform.auto and ResolvePath.joinZ which mishandle Windows paths; replace that logic with bun.path utilities (e.g., use bun.path.isAbsolute to check absolute paths and bun.path.resolve or bun.path.join/normalize to join cwd and relative path) so Windows drive letters and backslashes are handled correctly, then dup the resulting path with this.allocator.dupe(u8, resolvedPath) and return or handle OOM as before.

coderabbitai · 2025-12-25T06:39:11Z

+fn extractFileArgs(ctx: *TraceContext, cmd: *const ast.Cmd) std.array_list.Managed([]const u8) {
+    var file_args = std.array_list.Managed([]const u8).init(ctx.allocator);
+
+    for (cmd.name_and_args[1..]) |*arg| {
+        var expanded_list = expandAtomMultiple(ctx, arg);
+        defer expanded_list.deinit();
+
+        for (expanded_list.items) |expanded| {
+            if (expanded.len > 0 and expanded[0] != '-') {
+                // Keep this path - transfer ownership
+                bun.handleOom(file_args.append(expanded));
+            } else {
+                ctx.allocator.free(expanded);
+            }
+        }
+    }
+
+    // Expand glob patterns (e.g., *.txt -> file1.txt, file2.txt)
+    expandGlobs(ctx, &file_args);
+
+    return file_args;
+}
+
+/// Free a list of file args
+fn freeFileArgs(ctx: *TraceContext, file_args: *std.array_list.Managed([]const u8)) void {
+    for (file_args.items) |path| {
+        ctx.allocator.free(path);
+    }
+    file_args.deinit();
+}


🧹 Nitpick | 🔵 Trivial

Use unmanaged ArrayList for consistency.

The extractFileArgs and freeFileArgs functions use std.array_list.Managed, but per maintainer feedback, prefer std.ArrayListUnmanaged to avoid storing the allocator.

This applies to similar temporary lists throughout the file (e.g., line 861 in traceExternalCommand, line 1047 in expandGlobs).

🤖 Prompt for AI Agents

In src/shell/TraceInterpreter.zig around lines 671 to 700, the functions use std.array_list.Managed for temporary file argument lists; change these to std.ArrayListUnmanaged([]const u8) to avoid storing the allocator. Replace the type declaration and the .init(...) call to the corresponding ArrayListUnmanaged initializer, keep using the same append/error handling logic (bun.handleOom on append), and keep the same element free loop and deinit call but using the ArrayListUnmanaged deinit. Apply the same replacement pattern to the other occurrences mentioned (traceExternalCommand around line 861 and expandGlobs around line 1047).

coderabbitai · 2025-12-25T06:39:11Z

+// Permission flags (octal) - mirrors the Zig constants
+const Permission = {
+  O_RDONLY: 0o0,
+  O_WRONLY: 0o1,
+  O_RDWR: 0o2,
+  O_CREAT: 0o100,
+  O_EXCL: 0o200,
+  O_TRUNC: 0o1000,
+  O_APPEND: 0o2000,
+  X_OK: 0o100000,
+  DELETE: 0o200000,
+  MKDIR: 0o400000,
+  CHDIR: 0o1000000,
+  ENV: 0o2000000,
+} as const;
+
+// Convenience combinations
+const READ = Permission.O_RDONLY;
+const WRITE = Permission.O_WRONLY;
+const CREATE = Permission.O_CREAT | Permission.O_WRONLY;
+const CREATE_TRUNC = Permission.O_CREAT | Permission.O_TRUNC | Permission.O_WRONLY;
+const APPEND = Permission.O_APPEND | Permission.O_WRONLY;
+const EXECUTE = Permission.X_OK;
+


⚠️ Potential issue | 🟡 Minor

Keep Permission constants in sync with Zig-side trace flags

The local Permission table and derived aliases (READ, WRITE, CREATE, etc.) are hard-coded to mirror the Zig flag values. That’s fine for tests, but if the Zig-side bit layout changes, these expectations will silently become wrong.

Consider adding a short comment pointing to the Zig enum/bitmask source (file + symbol name), and be prepared to update these constants alongside any future changes to the trace flag definitions.

🤖 Prompt for AI Agents

In test/js/bun/shell/trace.test.ts around lines 5 to 28, the Permission constants and derived aliases are hard-coded to mirror Zig trace flags which can drift if the Zig bitmask changes; add a short comment above the Permission block pointing to the authoritative Zig source (file path and enum/bitmask symbol name) and include a reminder to update these JS constants when the Zig definition changes, e.g., "See <ZIG_FILE_PATH>:<SYMBOL_NAME> for canonical values — keep in sync"; no functional code changes required, just add that comment and a one-line note about updating the aliases when the Zig enum is modified.

coderabbitai · 2025-12-25T06:39:11Z

+  test("external command resolves path when available", () => {
+    // Use a cross-platform external command
+    const cmd = process.platform === "win32" ? "cmd" : "/bin/ls";
+    const result = $.trace`${cmd} --version`;
+    expect(result.success).toBe(true);
+
+    const execOps = result.operations.filter(op => op.flags === EXECUTE);
+    expect(execOps.length).toBeGreaterThan(0);
+    // Command name should be captured
+    expect(execOps[0].command).toBe(cmd);
+  });
+
+  test("external commands include args array", () => {
+    const result = $.trace`grep -r 'pattern' src/`;
+    expect(result.success).toBe(true);
+
+    const execOps = result.operations.filter(op => op.flags === EXECUTE);
+    expect(execOps.length).toBe(1);
+    expect(execOps[0].command).toBe("grep");
+    expect(execOps[0].args).toEqual(["-r", "pattern", "src/"]);
+  });
+
+  test("pipeline commands each have their own args", () => {
+    const result = $.trace`git diff HEAD^ -- src/ | head -100`;
+    expect(result.success).toBe(true);
+
+    const execOps = result.operations.filter(op => op.flags === EXECUTE);
+    expect(execOps.length).toBe(2);
+
+    expect(execOps[0].command).toBe("git");
+    expect(execOps[0].args).toEqual(["diff", "HEAD^", "--", "src/"]);
+
+    expect(execOps[1].command).toBe("head");
+    expect(execOps[1].args).toEqual(["-100"]);
+  });


🧹 Nitpick | 🔵 Trivial

Consider narrowing external-command expectations to avoid over-constraining implementation

Several tests around external commands (cmd//bin/ls, grep, git, head) assert exact command and args arrays. If the Zig trace implementation ever normalizes command names (e.g. strips directory components, resolves cmd.exe vs cmd) or tweaks argument splitting, these tests will fail even though the trace remains semantically correct.

If you start hitting spurious failures here, consider relaxing these to:

Check execOps[0].command endsWith the expected binary name rather than strict equality.

Assert key arguments are present/in order, but not the entire array (or use toContain for non-structural bits).

For now the tests are fine, but they do lock in fairly specific implementation details.

🤖 Prompt for AI Agents

In test/js/bun/shell/trace.test.ts around lines 274-308, the tests assert exact equality of exec operation command names and full args arrays which over-constrains implementations that may normalize command paths or split/normalize args; change assertions to be more flexible by checking that execOps[i].command endsWith the expected binary name (e.g., "git", "grep", "head" or "cmd") instead of strict equality, and validate important arguments by checking presence/order (e.g., toContain / indexOf checks or matching slices) rather than asserting the entire args array equals a specific array.

Normalize path separators using replaceAll("\\", "/") for cross-platform compatibility in shell trace tests. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

coderabbitai

Actionable comments posted: 2

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📥 Commits

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📒 Files selected for processing (1)

test/js/bun/shell/trace.test.ts

🧰 Additional context used

📓 Path-based instructions (3)

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}

📄 CodeRabbit inference engine (test/CLAUDE.md)

test/**/*.test.{ts,js,jsx,tsx,mjs,cjs}: Use bun:test with files that end in *.test.{ts,js,jsx,tsx,mjs,cjs}
Do not write flaky tests. Never wait for time to pass in tests; always wait for the condition to be met instead of using an arbitrary amount of time
Never use hardcoded port numbers in tests. Always use port: 0 to get a random port
Prefer concurrent tests over sequential tests using test.concurrent or describe.concurrent when multiple tests spawn processes or write files, unless it's very difficult to make them concurrent
When spawning Bun processes in tests, use bunExe and bunEnv from harness to ensure the same build of Bun is used and debug logging is silenced
Use -e flag for single-file tests when spawning Bun processes
Use tempDir() from harness to create temporary directories with files for multi-file tests instead of creating files manually
Prefer async/await over callbacks in tests
When callbacks must be used and it's just a single callback, use Promise.withResolvers to create a promise that can be resolved or rejected from a callback
Do not set a timeout on tests. Bun already has timeouts
Use Buffer.alloc(count, fill).toString() instead of 'A'.repeat(count) to create repetitive strings in tests, as ''.repeat is very slow in debug JavaScriptCore builds
Use describe blocks for grouping related tests
Always use await using or using to ensure proper resource cleanup in tests for APIs like Bun.listen, Bun.connect, Bun.spawn, Bun.serve, etc
Always check exit codes and test error scenarios in error tests
Use describe.each() for parameterized tests
Use toMatchSnapshot() for snapshot testing
Use beforeAll(), afterEach(), beforeEach() for setup/teardown in tests
Track resources (servers, clients) in arrays for cleanup in afterEach()

Files:

test/js/bun/shell/trace.test.ts

**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

**/*.test.ts?(x): Never use bun test directly - always use bun bd test to run tests with debug build changes
For single-file tests, prefer -e flag over tempDir
For multi-file tests, prefer tempDir and Bun.spawn over single-file tests
Use normalizeBunSnapshot to normalize snapshot output of tests
Never write tests that check for 'panic', 'uncaught exception', or similar strings in test output
Use tempDir from harness to create temporary directories - do not use tmpdirSync or fs.mkdtempSync
When spawning processes in tests, expect stdout before expecting exit code for more useful error messages on test failure
Do not write flaky tests - do not use setTimeout in tests; instead await the condition to be met
Verify tests fail with USE_SYSTEM_BUN=1 bun test <file> and pass with bun bd test <file> - tests are invalid if they pass with USE_SYSTEM_BUN=1
Test files must end with .test.ts or .test.tsx
Avoid shell commands like find or grep in tests - use Bun's Glob and built-in tools instead

Files:

test/js/bun/shell/trace.test.ts

test/**/*.test.ts?(x)

📄 CodeRabbit inference engine (CLAUDE.md)

Always use port: 0 in tests - do not hardcode ports or use custom random port number functions

Files:

test/js/bun/shell/trace.test.ts

🧠 Learnings (30)

📓 Common learnings

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 22606
File: src/glob/GlobWalker.zig:449-452
Timestamp: 2025-09-12T18:16:50.754Z
Learning: For Bun codebase: prefer using `std.fs.path.sep` over manual platform separator detection, and use `bun.strings.lastIndexOfChar` instead of `std.mem.lastIndexOfScalar` for string operations.

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 24719
File: docs/bundler/executables.mdx:527-560
Timestamp: 2025-11-14T16:07:01.064Z
Learning: In the Bun repository, certain bundler features like compile with code splitting (--compile --splitting) are CLI-only and not supported in the Bun.build() JavaScript API. Tests for CLI-only features use backend: "cli" flag (e.g., test/bundler/bundler_compile_splitting.test.ts). The CompileBuildConfig interface correctly restricts these with splitting?: never;. When documenting CLI-only bundler features, add a note clarifying they're not available via the programmatic API.

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Avoid shell commands like `find` or `grep` in tests - use Bun's Glob and built-in tools instead

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to src/bun.js/bindings/**/*.cpp : Cache structures in ZigGlobalObject for JavaScript class bindings

📚 Learning: 2025-11-24T18:36:59.706Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/bun.js/bindings/v8/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:36:59.706Z
Learning: Applies to src/bun.js/bindings/v8/test/v8/v8.test.ts : Add corresponding test cases to test/v8/v8.test.ts using checkSameOutput() function to compare Node.js and Bun output

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : When spawning Bun processes in tests, use `bunExe` and `bunEnv` from `harness` to ensure the same build of Bun is used and debug logging is silenced

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Verify tests fail with `USE_SYSTEM_BUN=1 bun test <file>` and pass with `bun bd test <file>` - tests are invalid if they pass with USE_SYSTEM_BUN=1

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Avoid shell commands like `find` or `grep` in tests - use Bun's Glob and built-in tools instead

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Never use `bun test` directly - always use `bun bd test` to run tests with debug build changes

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-19T02:44:46.354Z

Learnt from: theshadow27
Repo: oven-sh/bun PR: 23798
File: packages/bun-otel/context-propagation.test.ts:1-1
Timestamp: 2025-10-19T02:44:46.354Z
Learning: In the Bun repository, standalone packages under packages/ (e.g., bun-vscode, bun-inspector-protocol, bun-plugin-yaml, bun-plugin-svelte, bun-debug-adapter-protocol, bun-otel) co-locate their tests with package source code using *.test.ts files. This follows standard npm/monorepo patterns. The test/ directory hierarchy (test/js/bun/, test/cli/, test/js/node/) is reserved for testing Bun's core runtime APIs and built-in functionality, not standalone packages.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `$debug()` for debug logging and `$assert()` for assertions; both are stripped in release builds

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `-e` flag for single-file tests when spawning Bun processes

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For multi-file tests, prefer `tempDir` and `Bun.spawn` over single-file tests

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Use `normalizeBunSnapshot` to normalize snapshot output of tests

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:11.466Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: src/js/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:11.466Z
Learning: Applies to src/js/{builtins,node,bun,thirdparty,internal}/**/*.{ts,js} : Use `process.platform` and `process.arch` for platform detection; these values are inlined and dead-code eliminated at build time

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/js/node/test/{parallel,sequential}/*.js : For test/js/node/test/{parallel,sequential}/*.js files without a .test extension, use `bun bd <file>` instead of `bun bd test <file>` since these expect exit code 0 and don't use bun's test runner

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : For single-file tests, prefer `-e` flag over `tempDir`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-26T01:32:04.844Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 24082
File: test/cli/test/coverage.test.ts:60-112
Timestamp: 2025-10-26T01:32:04.844Z
Learning: In the Bun repository test files (test/cli/test/*.test.ts), when spawning Bun CLI commands with Bun.spawnSync for testing, prefer using stdio: ["inherit", "inherit", "inherit"] to inherit stdio streams rather than piping them.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `tempDir()` from harness to create temporary directories with files for multi-file tests instead of creating files manually

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Use `tempDir` from `harness` to create temporary directories - do not use `tmpdirSync` or `fs.mkdtempSync`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Always use `await using` or `using` to ensure proper resource cleanup in tests for APIs like Bun.listen, Bun.connect, Bun.spawn, Bun.serve, etc

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*-fixture.ts : Test files that spawn Bun processes should end in `*-fixture.ts` to identify them as test fixtures and not tests themselves

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-09-12T18:16:50.754Z

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 22606
File: src/glob/GlobWalker.zig:449-452
Timestamp: 2025-09-12T18:16:50.754Z
Learning: For Bun codebase: prefer using `std.fs.path.sep` over manual platform separator detection, and use `bun.strings.lastIndexOfChar` instead of `std.mem.lastIndexOfScalar` for string operations.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-15T22:03:50.832Z

Learnt from: markovejnovic
Repo: oven-sh/bun PR: 23710
File: src/envvars.zig:135-144
Timestamp: 2025-10-15T22:03:50.832Z
Learning: In src/envvars.zig, the boolean feature flag cache uses a single atomic enum and should remain monotonic. Only the string cache (which uses two atomics: ptr and len) requires acquire/release ordering to prevent torn reads.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-09-02T18:25:27.976Z

Learnt from: taylordotfish
Repo: oven-sh/bun PR: 22227
File: src/allocators/allocation_scope.zig:284-314
Timestamp: 2025-09-02T18:25:27.976Z
Learning: In bun's custom Zig implementation, the `#` prefix for private fields is valid syntax and should not be flagged as invalid. The syntax `#fieldname` creates private fields that cannot be accessed from outside the defining struct, and usage like `self.#fieldname` is correct within the same struct. This applies to fields like `#parent`, `#state`, `#allocator`, `#trace`, etc. throughout the codebase.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-11T02:11:47.024Z

Learnt from: Jarred-Sumner
Repo: oven-sh/bun PR: 25462
File: src/ast/visitExpr.zig:1644-1695
Timestamp: 2025-12-11T02:11:47.024Z
Learning: In Bun's bundler feature flag implementation (src/ast/visitExpr.zig), the validation for feature() flag names intentionally only rejects UTF-16 strings (checking `is_utf16`) while allowing UTF-8 strings, even though the error message says "must be an ASCII string". This is the intended behavior and should not be changed to enforce strict ASCII validation.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-10-18T20:50:47.750Z

Learnt from: theshadow27
Repo: oven-sh/bun PR: 23798
File: src/bun.js/telemetry.zig:366-373
Timestamp: 2025-10-18T20:50:47.750Z
Learning: In Bun's Zig codebase (src/bun.js/bindings/JSValue.zig), the JSValue enum uses `.null` (not `.js_null`) for JavaScript's null value. Only `js_undefined` has the `js_` prefix to avoid collision with Zig's built-in `undefined` keyword. The correct enum fields are: `js_undefined`, `null`, `true`, `false`, and `zero`.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : When spawning processes in tests, expect stdout before expecting exit code for more useful error messages on test failure

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-12-16T00:21:32.179Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: CLAUDE.md:0-0
Timestamp: 2025-12-16T00:21:32.179Z
Learning: Applies to **/*.test.ts?(x) : Never write tests that check for 'panic', 'uncaught exception', or similar strings in test output

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Always check exit codes and test error scenarios in error tests

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-09-07T08:20:47.215Z

Learnt from: RiskyMH
Repo: oven-sh/bun PR: 22258
File: src/cli/test_command.zig:1258-1281
Timestamp: 2025-09-07T08:20:47.215Z
Learning: For Bun's test line filtering feature, the parseFileLineArg function should only handle the specific cases of "file:line" and "file:line:col" formats. It should not try to be overly tolerant of other patterns, as components like ":col" or other non-numeric segments could legitimately be part of filenames. The current conservative approach that checks for numeric segments in expected positions is appropriate.

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-24T18:37:30.259Z

Learnt from: CR
Repo: oven-sh/bun PR: 0
File: test/CLAUDE.md:0-0
Timestamp: 2025-11-24T18:37:30.259Z
Learning: Applies to test/**/*.test.{ts,js,jsx,tsx,mjs,cjs} : Use `bun:test` with files that end in `*.test.{ts,js,jsx,tsx,mjs,cjs}`

Applied to files:

test/js/bun/shell/trace.test.ts

📚 Learning: 2025-11-07T17:28:51.204Z

Learnt from: markovejnovic
Repo: oven-sh/bun PR: 24423
File: test/js/node/path/browserify.test.js:472-475
Timestamp: 2025-11-07T17:28:51.204Z
Learning: In test files under test/js/node/path/, markovejnovic prefers functional programming patterns (e.g., reduce, map, filter chains) over imperative loops for clarity and readability.

Applied to files:

test/js/bun/shell/trace.test.ts

🧬 Code graph analysis (1)

test/js/bun/shell/trace.test.ts (3)

scripts/utils.mjs (1)

$ (143-161)

test/harness.ts (1)

tempDir (277-284)

scripts/glob-sources.mjs (1)

paths (9-9)

🔇 Additional comments (1)

test/js/bun/shell/trace.test.ts (1)
277-287: Verify command name assertion handles path resolution.

This test correctly uses platform-specific commands (cmd on Windows, /bin/ls on Unix). However, line 286 asserts execOps[0].command).toBe(cmd) which may be fragile if the trace interpreter resolves commands to full paths (e.g., C:\Windows\System32\cmd.exe instead of cmd).

If Windows tests fail at this assertion, consider using endsWith() instead of strict equality:
-    expect(execOps[0].command).toBe(cmd);
+    expect(execOps[0].command).toContain(cmd.split("/").pop()!);
Or verify the trace implementation returns normalized command names without paths.

coderabbitai · 2025-12-28T01:18:59Z

+  test("traces cat command with file read", () => {
+    const result = $.trace`cat /tmp/test.txt`;
+    expect(result.success).toBe(true);
+
+    // cat is a builtin - it reads files but runs in-process (no EXECUTE)
+    const readOps = result.operations.filter(op => op.flags === READ && op.path?.endsWith("test.txt"));
+    expect(readOps.length).toBe(1);
+    expect(normalizePath(readOps[0].path!)).toBe("/tmp/test.txt");
+  });
+
+  test("traces rm command with delete permission", () => {
+    const result = $.trace`rm /tmp/to-delete.txt`;
+    expect(result.success).toBe(true);
+
+    // Should have delete for the file
+    const deleteOps = result.operations.filter(op => op.flags === Permission.DELETE);
+    expect(deleteOps.length).toBe(1);
+    expect(normalizePath(deleteOps[0].path!)).toBe("/tmp/to-delete.txt");
+  });
+
+  test("traces mkdir command", () => {
+    const result = $.trace`mkdir /tmp/newdir`;
+    expect(result.success).toBe(true);
+
+    // Should have mkdir permission
+    const mkdirOps = result.operations.filter(op => op.flags === Permission.MKDIR);
+    expect(mkdirOps.length).toBe(1);
+    expect(normalizePath(mkdirOps[0].path!)).toBe("/tmp/newdir");
+  });
+
+  test("traces touch command with create permission", () => {
+    const result = $.trace`touch /tmp/newfile.txt`;
+    expect(result.success).toBe(true);
+
+    // Should have create permission
+    const createOps = result.operations.filter(op => op.flags === CREATE);
+    expect(createOps.length).toBe(1);
+    expect(normalizePath(createOps[0].path!)).toBe("/tmp/newfile.txt");
+  });
+
+  test("traces cp command with read and write", () => {
+    const result = $.trace`cp /tmp/src.txt /tmp/dst.txt`;
+    expect(result.success).toBe(true);
+
+    // Should have read for source
+    const readOps = result.operations.filter(op => op.flags === READ && op.path?.endsWith("src.txt"));
+    expect(readOps.length).toBe(1);
+
+    // Should have create for destination
+    const writeOps = result.operations.filter(op => op.flags === CREATE && op.path?.endsWith("dst.txt"));
+    expect(writeOps.length).toBe(1);
+  });
+
+  test("traces mv command with read, delete, and write", () => {
+    const result = $.trace`mv /tmp/old.txt /tmp/new.txt`;
+    expect(result.success).toBe(true);
+
+    // Should have read+delete for source (combined in one operation)
+    const srcOps = result.operations.filter(
+      op => op.flags === (READ | Permission.DELETE) && op.path?.endsWith("old.txt"),
+    );
+    expect(srcOps.length).toBe(1);
+
+    // Should have create for destination
+    const dstOps = result.operations.filter(op => op.flags === CREATE && op.path?.endsWith("new.txt"));
+    expect(dstOps.length).toBe(1);
+  });
+
+  test("traces cd command with chdir permission", () => {
+    const result = $.trace`cd /tmp`;
+    expect(result.success).toBe(true);
+
+    const chdirOps = result.operations.filter(op => op.flags === Permission.CHDIR);
+    expect(chdirOps.length).toBe(1);
+    expect(normalizePath(chdirOps[0].path!)).toBe("/tmp");
+  });
+
+  test("traces environment variable assignments with accumulated env", () => {
+    const result = $.trace`FOO=1 BAR=2 echo test`;
+    expect(result.success).toBe(true);
+
+    const envOps = result.operations.filter(op => op.flags === Permission.ENV);
+    expect(envOps.length).toBe(2);
+    // First op has FOO
+    expect(envOps[0].env).toEqual({ FOO: "1" });
+    // Second op has both FOO and BAR
+    expect(envOps[1].env?.FOO).toBe("1");
+    expect(envOps[1].env?.BAR).toBe("2");
+  });
+
+  test("traces export with env values", () => {
+    const result = $.trace`export FOO=hello BAR=world`;
+    expect(result.success).toBe(true);
+
+    const envOps = result.operations.filter(op => op.flags === Permission.ENV);
+    expect(envOps.length).toBe(1);
+    expect(envOps[0].env?.FOO).toBe("hello");
+    expect(envOps[0].env?.BAR).toBe("world");
+  });
+
+  test("traces output redirection combined with command", () => {
+    const result = $.trace`echo hello > /tmp/output.txt`;
+    expect(result.success).toBe(true);
+
+    // echo is a builtin - redirect creates the output file (CREATE_TRUNC, no EXECUTE)
+    const redirectOps = result.operations.filter(op => op.flags === CREATE_TRUNC && op.path?.endsWith("output.txt"));
+    expect(redirectOps.length).toBe(1);
+  });
+
+  test("traces append redirection combined with command", () => {
+    const result = $.trace`echo hello >> /tmp/append.txt`;
+    expect(result.success).toBe(true);
+
+    // echo is a builtin - append redirect opens file for appending (no EXECUTE)
+    const appendOps = result.operations.filter(op => op.flags === APPEND && op.path?.endsWith("append.txt"));
+    expect(appendOps.length).toBe(1);
+  });
+
+  test("traces input redirection with read and stdin stream", () => {
+    const result = $.trace`cat < /tmp/input.txt`;
+    expect(result.success).toBe(true);
+
+    // Should have read for input file with stdin stream marker
+    const stdinOps = result.operations.filter(
+      op => op.flags === READ && op.path?.endsWith("input.txt") && op.stream === "stdin",
+    );
+    expect(stdinOps.length).toBe(1);
+  });
+
+  test("traces stderr redirection with stream marker", () => {
+    const result = $.trace`cat /nonexistent 2> /tmp/err.txt`;
+    expect(result.success).toBe(true);
+
+    // Should have stderr stream for error redirect
+    const stderrOps = result.operations.filter(op => op.stream === "stderr" && op.path?.endsWith("err.txt"));
+    expect(stderrOps.length).toBe(1);
+    expect(stderrOps[0].flags).toBe(CREATE_TRUNC);
+  });
+
+  test("stdout redirect has stream marker", () => {
+    const result = $.trace`echo hello > /tmp/out.txt`;
+    expect(result.success).toBe(true);
+
+    const stdoutOps = result.operations.filter(op => op.stream === "stdout");
+    expect(stdoutOps.length).toBe(1);
+    expect(normalizePath(stdoutOps[0].path!)).toBe("/tmp/out.txt");
+  });
+
+  test("traces export command with env permission", () => {
+    const result = $.trace`export FOO=bar`;
+    expect(result.success).toBe(true);
+
+    const envOps = result.operations.filter(op => op.flags === Permission.ENV);
+    expect(envOps.length).toBeGreaterThan(0);
+  });
+
+  test("traces variable assignment with env permission", () => {
+    const result = $.trace`FOO=bar echo $FOO`;
+    expect(result.success).toBe(true);
+
+    const envOps = result.operations.filter(op => op.flags === Permission.ENV);
+    expect(envOps.length).toBeGreaterThan(0);
+  });
+
+  test("traces pipeline", () => {
+    const result = $.trace`cat /tmp/file.txt | grep pattern`;
+    expect(result.success).toBe(true);
+
+    // cat is a builtin - reads file (no EXECUTE, no command field)
+    const readOps = result.operations.filter(op => op.flags === READ && op.path?.endsWith("file.txt"));
+    expect(readOps.length).toBe(1);
+
+    // grep is external, should have execute permission and command field
+    const grepOps = result.operations.filter(op => op.command === "grep" && (op.flags & EXECUTE) !== 0);
+    expect(grepOps.length).toBe(1);
+  });
+
+  test("traces ls with directory read", () => {
+    const result = $.trace`ls /tmp`;
+    expect(result.success).toBe(true);
+
+    const readOps = result.operations.filter(op => op.flags === READ && normalizePath(op.path || "") === "/tmp");
+    expect(readOps.length).toBe(1);
+  });
+
+  test("traces ls without args (current dir)", () => {
+    const result = $.trace`ls`;
+    expect(result.success).toBe(true);
+
+    // Should read current directory (.)
+    const readOps = result.operations.filter(op => op.flags === READ);
+    expect(readOps.length).toBe(1);
+  });
+
+  test("includes cwd in result", () => {
+    const result = $.trace`echo test`;
+    expect(result.cwd).toBeTruthy();
+    expect(typeof result.cwd).toBe("string");
+  });
+
+  test("includes cwd in each operation", () => {
+    const result = $.trace`cat /tmp/test.txt`;
+    for (const op of result.operations) {
+      expect(op.cwd).toBeTruthy();
+      expect(typeof op.cwd).toBe("string");
+    }
+  });
+
+  test("handles template literal interpolation", () => {
+    const filename = "test.txt";
+    const result = $.trace`cat /tmp/${filename}`;
+    expect(result.success).toBe(true);
+
+    const readOps = result.operations.filter(op => op.flags === READ && op.path?.endsWith("test.txt"));
+    expect(readOps.length).toBe(1);
+  });
+
+  test("does not actually execute commands", () => {
+    // This would fail if it actually ran, since the file doesn't exist
+    const result = $.trace`cat /nonexistent/path/that/does/not/exist.txt`;
+    expect(result.success).toBe(true);
+    expect(result.operations.length).toBeGreaterThan(0);
+  });
+
+  test("external command resolves path when available", () => {
+    // Use a cross-platform external command
+    const cmd = process.platform === "win32" ? "cmd" : "/bin/ls";
+    const result = $.trace`${cmd} --version`;
+    expect(result.success).toBe(true);
+
+    const execOps = result.operations.filter(op => op.flags === EXECUTE);
+    expect(execOps.length).toBeGreaterThan(0);
+    // Command name should be captured
+    expect(execOps[0].command).toBe(cmd);
+  });
+
+  test("external commands include args array", () => {
+    const result = $.trace`grep -r 'pattern' src/`;
+    expect(result.success).toBe(true);
+
+    const execOps = result.operations.filter(op => op.flags === EXECUTE);
+    expect(execOps.length).toBe(1);
+    expect(execOps[0].command).toBe("grep");
+    expect(execOps[0].args).toEqual(["-r", "pattern", "src/"]);
+  });
+
+  test("pipeline commands each have their own args", () => {
+    const result = $.trace`git diff HEAD^ -- src/ | head -100`;
+    expect(result.success).toBe(true);
+
+    const execOps = result.operations.filter(op => op.flags === EXECUTE);
+    expect(execOps.length).toBe(2);
+
+    expect(execOps[0].command).toBe("git");
+    expect(execOps[0].args).toEqual(["diff", "HEAD^", "--", "src/"]);
+
+    expect(execOps[1].command).toBe("head");
+    expect(execOps[1].args).toEqual(["-100"]);
+  });
+
+  test("builtins do not have args (tracked as file operations)", () => {
+    const result = $.trace`cat file1.txt file2.txt`;
+    expect(result.success).toBe(true);
+
+    // Builtins track files, not args
+    const readOps = result.operations.filter(op => op.flags === READ);
+    expect(readOps.length).toBe(2);
+    expect(readOps[0].args).toBeUndefined();
+    expect(readOps[1].args).toBeUndefined();
+  });
+
+  test("traces && (and) operator", () => {
+    const result = $.trace`cat /tmp/a.txt && cat /tmp/b.txt`;
+    expect(result.success).toBe(true);
+
+    // Both commands should be traced
+    const readOps = result.operations.filter(op => op.flags === READ);
+    expect(readOps.length).toBe(2);
+    expect(normalizePath(readOps[0].path!)).toBe("/tmp/a.txt");
+    expect(normalizePath(readOps[1].path!)).toBe("/tmp/b.txt");
+  });
+
+  test("traces || (or) operator", () => {
+    const result = $.trace`cat /tmp/a.txt || cat /tmp/b.txt`;
+    expect(result.success).toBe(true);
+
+    // Both commands should be traced
+    const readOps = result.operations.filter(op => op.flags === READ);
+    expect(readOps.length).toBe(2);
+  });
+
+  test("traces subshell with cwd isolation", () => {
+    const result = $.trace`(cd /tmp && ls) && ls`;
+    expect(result.success).toBe(true);
+
+    // Should have: CHDIR /tmp, READ /tmp (inside subshell), READ . (outside subshell)
+    const chdirOps = result.operations.filter(op => op.flags === Permission.CHDIR);
+    expect(chdirOps.length).toBe(1);
+    expect(normalizePath(chdirOps[0].path!)).toBe("/tmp");
+
+    const readOps = result.operations.filter(op => op.flags === READ);
+    expect(readOps.length).toBe(2);
+    // First ls inside subshell should see /tmp
+    expect(normalizePath(readOps[0].cwd!)).toBe("/tmp");
+    // Second ls outside subshell should see original cwd (subshell cwd is restored)
+    expect(normalizePath(readOps[1].cwd!)).not.toBe("/tmp");
+  });
+
+  test("cd updates cwd for subsequent commands", () => {
+    const result = $.trace`cd /tmp && ls`;
+    expect(result.success).toBe(true);
+
+    const readOps = result.operations.filter(op => op.flags === READ);
+    expect(readOps.length).toBe(1);
+    expect(normalizePath(readOps[0].cwd!)).toBe("/tmp");
+    expect(normalizePath(readOps[0].path!)).toBe("/tmp"); // ls reads cwd
+  });


⚠️ Potential issue | 🔴 Critical

Critical: Hardcoded /tmp paths cause Windows test failures.

The PR objectives report Windows test failures for this file on Windows 2019 x64 and x64-baseline. Lines 53-369 contain ~25 tests using hardcoded Unix paths like /tmp/test.txt, /tmp/newdir, etc. The /tmp directory doesn't exist on Windows, and the normalizePath helper (line 6) only converts path separators without addressing the root cause.

While $.trace doesn't actually execute commands (verified at lines 270-275), the trace interpreter processes these paths in platform-specific ways that fail on Windows.

Recommended fix:

For tests that need real filesystem paths, use tempDir() from harness (as the glob test correctly does at lines 398-416). For tests that only need path strings for tracing, use os.tmpdir() to get platform-appropriate temp directory:

import { tmpdir } from "os"; // At top of describe block or as a helper const getTempPath = (filename: string) => `${tmpdir()}/${filename}`; // In tests: const result = $.trace`cat ${getTempPath("test.txt")}`;

Alternatively, if these tests are Unix-specific by design, add test.skipIf(isWindows) guards to each test. However, given that trace is a cross-platform feature, fixing the paths to be portable is preferable.

As per coding guidelines and based on the Windows test failures reported in the PR.

🤖 Prompt for AI Agents

In test/js/bun/shell/trace.test.ts around lines 53 to 369, many tests use hardcoded Unix paths like "/tmp/…", which breaks on Windows; replace those hardcoded paths with platform-safe temp paths by importing os.tmpdir() (or the harness tempDir() helper) and adding a small helper (e.g., getTempPath(filename)) at the top of the describe block, then update each test to call that helper for any filename/path currently using "/tmp/..."; alternatively mark tests as skipped on Windows only if they truly must be Unix-specific. Ensure all assertions that compare normalized paths use normalizePath(getTempPath(...)) where applicable.

coderabbitai · 2025-12-28T01:18:59Z

+  test("expands glob patterns to matching files", () => {
+    // Create test files for glob expansion using tempDir helper
+    const { join } = require("path");
+    using dir = tempDir("trace-glob-test", {
+      "a.txt": "",
+      "b.txt": "",
+      "c.txt": "",
+    });
+    const testDir = String(dir);
+
+    const result = $.trace`cat ${testDir}/*.txt`;
+    expect(result.success).toBe(true);
+
+    const readOps = result.operations.filter(op => op.flags === READ);
+    expect(readOps.length).toBe(3);
+    const paths = readOps.map(op => normalizePath(op.path!)).sort();
+    const expected = [join(testDir, "a.txt"), join(testDir, "b.txt"), join(testDir, "c.txt")].map(normalizePath);
+    expect(paths).toEqual(expected);
+  });


🧹 Nitpick | 🔵 Trivial

Excellent use of tempDir and using for cleanup.

This test correctly follows coding guidelines by using tempDir() from harness to create temporary test files and using for automatic cleanup. This is the pattern that other tests in this file should follow (see comment on lines 53-369).

Minor: Import path at the top instead of inline require.

Line 400 uses require("path") inline. For consistency, consider importing join at the file top with the other imports:

import { $ } from "bun"; import { describe, expect, test } from "bun:test"; import { tempDir } from "harness"; +import { join } from "path";

Then remove the inline require at line 400.

Committable suggestion skipped: line range outside the PR's diff.

🤖 Prompt for AI Agents

In test/js/bun/shell/trace.test.ts around lines 398 to 416, remove the inline require("path") call and instead add an import for join at the top of the file with the other imports; then delete the inline require line and keep using join as before. Ensure the top-of-file import uses the same module style as the file (e.g., import { join } from "path") so linter/formatting remains consistent.

…on (oven-sh#25667) ## Summary Adds `Bun.$.trace` for tracing shell commands without executing them. ```js const result = $.trace`cat /tmp/file.txt > output.txt`; // { operations: [...], cwd: "...", success: true, error: null } ``` ## Test plan - [x] `bun bd test test/js/bun/shell/trace.test.ts` 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Bot <claude-bot@bun.sh> Co-authored-by: Claude <noreply@anthropic.com> Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com> Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>

… execution (#25667)" This reverts commit 6b5de25.

github-actions Bot added the claude label Dec 24, 2025

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robobun force-pushed the claude/shell-trace-interpreter branch from bccf368 to 8a218a5 Compare December 24, 2025 00:35

[autofix.ci] apply automated fixes

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Comment thread src/shell/TraceInterpreter.zig

Claude Bot and others added 2 commits December 24, 2025 02:05

[autofix.ci] apply automated fixes

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Claude Bot and others added 3 commits December 24, 2025 02:28

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Comment thread test/js/bun/shell/trace.test.ts

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Jarred-Sumner and others added 2 commits December 24, 2025 19:27

Merge branch 'main' into claude/shell-trace-interpreter

d9e9e0f

coderabbitai Bot reviewed Dec 25, 2025

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Fix Windows path separator in trace tests

7a333e5

Normalize path separators using replaceAll("\\", "/") for cross-platform compatibility in shell trace tests. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

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Jarred-Sumner merged commit 6b5de25 into main Dec 28, 2025
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Jarred-Sumner deleted the claude/shell-trace-interpreter branch December 28, 2025 01:25

Jarred-Sumner added a commit that referenced this pull request Jan 10, 2026

Revert "feat(shell): add $.trace for analyzing shell commands without…

1e0f51d

… execution (#25667)" This reverts commit 6b5de25.

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robobun commented Dec 24, 2025 •

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robobun commented Dec 24, 2025 •

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