bun check: TypeScript 7.1

completions/bun.bash

@@ -201,10 +201,10 @@ _bun_completions() {
             COMPREPLY=( $(compgen -W "--bun --package --no-install --cwd --env-file --minimum-release-age --trust --verbose --silent --help -p -h" -- "${cur_word}") );
             return;;
         check)
-            COMPREPLY=( $(compgen -f -W "--project --pretty --build --no-pretty --all --threads --timing --cwd --no-script --help -p -b -h" -- "${cur_word}") );
+            COMPREPLY=( $(compgen -f -W "--project --pretty --build --no-pretty --all --threads --timing --cwd --no-script --runExternalCode --help -p -b -h" -- "${cur_word}") );
             return;;
         lint)
-            COMPREPLY=( $(compgen -f -W "--config --no-config-lookup --rule --rules --explain --init --global --no-inline-config --report-unused-disable-directives --print-config --doctor --allow-unsupported --staged --changed --ignore-pattern --ignore-path --no-ignore --ext --stdin --stdin-filename --list-files --no-error-on-unmatched-pattern --cwd --format --all --output-file --quiet --max-warnings --color --no-color --timing --fix --fix-dry-run --fix-type --fix-suggestions --fix-dangerously --type-aware --no-type-aware --tsconfig --type-check --infer-globals --no-infer-globals --threads --no-script --version --help --help-all --flavor --project --parser-options --parser --plugin --native-plugin-rules --no-native-plugin-rules --report-unused-disable-directives-severity --report-unused-inline-configs --no-warn-ignored --suppress-all --suppress-rule --suppressions-location --prune-suppressions --pass-on-unpruned-suppressions --pass-on-no-patterns --exit-on-fatal-error --concurrency --env-info --no-eslintrc --env --rulesdir --resolve-plugins-relative-to --allow --warn --deny --deny-warnings --silent --disable-nested-config --import-plugin --react-plugin --jsdoc-plugin --jest-plugin --vitest-plugin --jsx-a11y-plugin --nextjs-plugin --react-perf-plugin --promise-plugin --node-plugin --vue-plugin --disable-unicorn-plugin --disable-oxc-plugin --disable-typescript-plugin -c -f -o -v -h -p -A -W -D" -- "${cur_word}") );
+            COMPREPLY=( $(compgen -f -W "--config --no-config-lookup --rule --rules --explain --init --global --no-inline-config --report-unused-disable-directives --print-config --doctor --allow-unsupported --staged --changed --ignore-pattern --ignore-path --no-ignore --ext --stdin --stdin-filename --list-files --no-error-on-unmatched-pattern --cwd --format --all --output-file --quiet --verbose --max-warnings --color --no-color --timing --fix --fix-dry-run --fix-type --fix-suggestions --fix-dangerously --type-aware --no-type-aware --tsconfig --type-check --infer-globals --no-infer-globals --threads --no-script --version --help --help-all --flavor --project --parser-options --parser --plugin --native-plugin-rules --no-native-plugin-rules --report-unused-disable-directives-severity --report-unused-inline-configs --no-warn-ignored --suppress-all --suppress-rule --suppressions-location --prune-suppressions --pass-on-unpruned-suppressions --pass-on-no-patterns --exit-on-fatal-error --concurrency --env-info --no-eslintrc --env --rulesdir --resolve-plugins-relative-to --allow --warn --deny --deny-warnings --silent --disable-nested-config --import-plugin --react-plugin --jsdoc-plugin --jest-plugin --vitest-plugin --jsx-a11y-plugin --nextjs-plugin --react-perf-plugin --promise-plugin --node-plugin --vue-plugin --disable-unicorn-plugin --disable-oxc-plugin --disable-typescript-plugin -c -f -o -v -h -p -A -W -D" -- "${cur_word}") );
             return;;
         fmt)
             COMPREPLY=( $(compgen -f -W "--config --no-config --no-editorconfig --init --doctor --print-width --tab-width --use-tabs --no-semi --single-quote --jsx-single-quote --quote-props --trailing-comma --no-bracket-spacing --bracket-same-line --arrow-parens --object-wrap --single-attribute-per-line --html-whitespace-sensitivity --vue-indent-script-and-style --prose-wrap --embedded-language-formatting --end-of-line --no-insert-final-newline --sort-imports --sort-tailwindcss --sort-package-json --jsdoc --svelte --no-svelte --staged --changed --stdin-filepath --ignore-path --ignore-pattern --with-node-modules --no-error-on-unmatched-pattern --ignore-unknown --allow-unsupported --list-files --cwd --check --list-different --log-level --format --color --no-color --timing --threads --debug-check --no-script --version --help --all --help-all --write --config-precedence --find-config-path --parser --plugin --require-pragma --check-ignore-pragma --insert-pragma --range-start --range-end --cursor-offset --experimental-ternaries --experimental-operator-position --jsx-bracket-same-line --flavor --disable-nested-config -u -c -l -f -v -h -w" -- "${cur_word}") );

completions/bun.fish

@@ -228,6 +228,7 @@ complete -c bun -n "__fish_seen_subcommand_from check" -l "threads" -r -d "Numbe
 complete -c bun -n "__fish_seen_subcommand_from check" -l "timing" -d "Print load and check times"
 complete -c bun -n "__fish_seen_subcommand_from check" -l "cwd" -r -d "Set the working directory"
 complete -c bun -n "__fish_seen_subcommand_from check" -l "no-script" -d "Run the type checker even if the project has a check script"
+complete -c bun -n "__fish_seen_subcommand_from check" -l "runExternalCode" -d "Run the programs from node_modules that contentMappers in tsconfig.json lists"
 complete -c bun -n "__fish_use_subcommand" -a "lint" -d "Lint JavaScript and TypeScript" -f
 complete -c bun -n "__fish_seen_subcommand_from lint" -s "c" -l "config" -r -F -d "Use this config file instead of looking for one"
 complete -c bun -n "__fish_seen_subcommand_from lint" -l "no-config-lookup" -d "Do not look for a config file"
@@ -256,6 +257,7 @@ complete -c bun -n "__fish_seen_subcommand_from lint" -s "f" -l "format" -r -d "
 complete -c bun -n "__fish_seen_subcommand_from lint" -l "all" -d "Show every problem (pretty and agent group identical problems above 50)"
 complete -c bun -n "__fish_seen_subcommand_from lint" -s "o" -l "output-file" -r -F -d "Write the report to a file"
 complete -c bun -n "__fish_seen_subcommand_from lint" -l "quiet" -d "Report errors only"
+complete -c bun -n "__fish_seen_subcommand_from lint" -l "verbose" -d "Print every note"
 complete -c bun -n "__fish_seen_subcommand_from lint" -l "max-warnings" -r -d "Exit with 1 if there are more warnings than this"
 complete -c bun -n "__fish_seen_subcommand_from lint" -l "color" -d "Always use colors"
 complete -c bun -n "__fish_seen_subcommand_from lint" -l "no-color" -d "Never use colors"

completions/bun.zsh

@@ -800,6 +800,7 @@ _bun_check_completion() {
         '--timing[Print load and check times]' \
         '--cwd[Set the working directory]:cwd:_files -/' \
         '--no-script[Run the type checker even if the project has a check script]' \
+        '--runExternalCode[Run the programs from node_modules that contentMappers in tsconfig.json lists]' \
         '--help[Print this help menu]' \
         '-h[Print this help menu]' &&
         ret=0
@@ -839,6 +840,7 @@ _bun_lint_completion() {
         '--output-file[Write the report to a file]:output-file:_files' \
         '-o[Write the report to a file]:output-file:_files' \
         '--quiet[Report errors only]' \
+        '--verbose[Print every note]' \
         '--max-warnings[Exit with 1 if there are more warnings than this]:max-warnings' \
         '--color[Always use colors]' \
         '--no-color[Never use colors]' \

docs/guides/lint/migrate-from-eslint.mdx

@@ -89,7 +89,7 @@ export default tseslint.config(...tseslint.configs.recommendedTypeChecked, {
 });
 ```
 
-The types come from Bun's built-in type checker ([`bun check`](/runtime/check)), not from the `typescript` package. It behaves like TypeScript 7.
+The types come from Bun's built-in type checker ([`bun check`](/runtime/check)), not from the `typescript` package. It behaves like TypeScript 7.1.
 
 ---
 

docs/runtime/bunfig.mdx

@@ -602,6 +602,7 @@ Every flag that makes sense as a default is also a key, in camelCase: `--max-war
 | `maxWarnings`                   | number                                | `--max-warnings`                                    |
 | `denyWarnings`                  | boolean                               | `--deny-warnings`                                   |
 | `quiet`                         | boolean                               | `--quiet`                                           |
+| `verbose`                       | boolean                               | `--verbose`                                         |
 | `silent`                        | boolean                               | `--silent`                                          |
 | `format`                        | name                                  | `-f`, `--format`                                    |
 | `all`                           | boolean                               | `--all`                                             |

docs/runtime/check.mdx

@@ -3,7 +3,7 @@ title: "Type checking"
 description: "Type check your TypeScript project with bun check"
 ---
 
-`bun check` type checks your TypeScript project. It reads your `tsconfig.json`, reports the same errors as `tsc` from TypeScript 7, and uses every CPU core.
+`bun check` type checks your TypeScript project. It reads your `tsconfig.json`, reports the same errors as `tsc` from TypeScript 7.1, and uses every CPU core.
 
 ```bash terminal icon="terminal"
 bun check
@@ -89,7 +89,7 @@ Keep `tsc` to generate `.d.ts` files. `bun check` only checks.
 
 ### Coming from TypeScript 5
 
-`bun check` behaves like TypeScript 7, whichever version of `typescript` you have installed. TypeScript 6 and 7 changed some defaults and removed some compiler options.
+`bun check` behaves like TypeScript 7.1, whichever version of `typescript` you have installed. TypeScript 6 and 7 changed some defaults and removed some compiler options.
 
 Three defaults changed:
 
@@ -620,7 +620,7 @@ Then tell your editor to use the version in your project. In VS Code, run **Type
 
 Run the command again after you upgrade Bun, because a new version of Bun can match a newer TypeScript.
 
-If `bun check` and `tsc` from TypeScript 7 report different errors, that is a bug in Bun. [Open an issue on GitHub](https://github.com/oven-sh/bun/issues) with code that shows the difference.
+If `bun check` and `tsc` from TypeScript 7.1 report different errors, that is a bug in Bun. [Open an issue on GitHub](https://github.com/oven-sh/bun/issues) with code that shows the difference.
 
 ## Compiler options as flags
 
@@ -640,17 +640,56 @@ A flag applies to the projects that `bun check` reports. With [`-b`](#every-proj
 bun check -b --strict
 ```
 
+## Vue, Svelte, Astro, and other file types
+
+TypeScript 7.1 adds content mappers. A content mapper is a program from a package in `node_modules` that turns a file TypeScript cannot read, such as a `.vue` file, into TypeScript. `bun check` checks the result and reports each error at the matching line and column of your file.
+
+List the mappers in `tsconfig.json`:
+
+```json tsconfig.json icon="file-json"
+{
+  "contentMappers": [{ "package": "my-vue-mapper", "extensions": [".vue"] }],
+  "include": ["src/**/*.ts", "src/**/*.vue"]
+}
+```
+
+Then pass `--runExternalCode`:
+
+```bash terminal icon="terminal"
+bun check --runExternalCode
+```
+
+```txt
+src/App.vue(12,7): error TS2322: Type 'string' is not assignable to type 'number'.
+```
+
+<Warning>
+  `--runExternalCode` lets the project choose programs that run on your computer with your permissions. The
+  `tsconfig.json` says which packages, and each package's `package.json` says which command. Use the flag only in
+  projects whose `tsconfig.json` and `node_modules` you trust.
+</Warning>
+
+The flag only works on the command line of `bun check`, after `check`. It has no effect in `tsconfig.json`, `bunfig.toml`, `BUN_OPTIONS`, or a response file (`@file`). Without the flag, `bun check` starts nothing and reports TS18068:
+
+```txt
+tsconfig.json(2,3): error TS18068: Content mappers require the '--runExternalCode' command line flag to be enabled.
+```
+
+`bun --check`, `bun test --check`, `bun build --check`, `Bun.build({ check: true })`, and `bun lint` never run a content mapper.
+
+Each mapper runs once per `bun check`, in its package's directory, and stops when the check ends. A mapper whose command is `node` runs with Bun if `node` is not installed. What it prints to standard error appears in your terminal. `bun check` does not trust what a mapper answers: an answer that is malformed or points outside of the file is an error on that file, and after five such files the mapper is not used again.
+
 ## Differences from `tsc`
 
-`bun check` aims to report exactly what `tsc` from TypeScript 7 reports. `process.versions.typescript` is the exact version.
+`bun check` aims to report exactly what `tsc` from TypeScript 7.1 reports. `process.versions.typescript` is the exact version.
 
 ```bash terminal icon="terminal"
 bun -p process.versions.typescript
 ```
 
 These differences are intentional:
 
-- **`bun check` only checks.** It does not write JavaScript, `.d.ts`, source map, or `.tsbuildinfo` files, even if `declaration` or `incremental` is on. Use [`bun build`](/bundler) to produce JavaScript and `tsc` to produce declaration files.
+- **`bun check` only checks.** It does not write JavaScript, `.d.ts`, source map, or `.tsbuildinfo` files, even if `declaration` or `incremental` is on. Use [`bun build`](/bundler) to produce JavaScript and `tsc` to produce declaration files. As with `tsc --noEmit`, errors about declaration files, such as TS4025 or the TS90xx errors of `isolatedDeclarations`, are reported once there are no other errors. `bun check -b` reports them next to other errors, like `tsc -b`, unless the project has `noEmit`.
 - **Referenced projects don't have to be built.** `tsc` without `-b` reads the `.d.ts` files that an earlier build wrote, and reports TS6305 if there are none. `bun check` reads the source files.
 - **Compiler options work with `-b`.** `tsc -b --strict` reports TS5094. `bun check -b --strict` applies the option to every project.
 - **A `tsconfig.json` with nothing but `references` is followed.** `tsc` without `-b` [checks nothing](#a-tsconfigjson-with-nothing-but-references) there.
@@ -659,6 +698,7 @@ These differences are intentional:
 - **An error that one file raises in another file is reported.** `tsc` collects the errors of a file right after it checks that file, so it drops an error that a later file raises in an earlier one. `bun check` reports it.
 - **A file that is too long affects no other file.** After TS2563 for the top-level code of one file, `tsc` stops following the types of variables and parameters in the files it checks next, so it drops errors there and reports false ones. `bun check` starts every file afresh.
 - **The order of projects does not change their options.** If configuration files extend each other in a circle, both tools report TS18000. `tsc` prints `{0}` where the files belong, and `bun check` lists them. What `tsc -b` then makes of those files for one project depends on which project it loaded first, and it can hang. `bun check -b` gives each project the options it has when you check it alone.
+- **A project on a network share is checked.** `tsc` reports TS5116 for every network path, so it refuses each file of a project in `\\server\share`. `bun check` checks that project. It may only name paths on `\\server`, and a path on any other server is still TS5116.
 - **The `lib.*.d.ts` files are built in.** An error or a declaration in one of them has a path such as `bundled:///libs/lib.dom.d.ts`, which is not a file on your disk.
 - **A note tells you when dependencies are missing.** If an import fails because a package in `package.json` is not installed, `bun check` adds a line that names the `package.json` and says how to run `bun install` for it.
 - **A note tells you when type checking did not run.** If a syntax error or an invalid option stops the check, `bun check` adds a line that says [how many files it did not check](#stopped-before-type-checking).
@@ -681,6 +721,7 @@ bun check [flags] [...files or directories]
 | `--no-pretty`            | One line per error, like `tsc --pretty false`. Default when piped   |
 | `--all`                  | Show every error. Without it, identical errors are grouped above 50 |
 | `--threads <n>`          | Number of threads. Default: one per CPU core                        |
+| `--runExternalCode`      | Run the programs that `contentMappers` in `tsconfig.json` lists     |
 | `--timing`               | Print how long loading and checking took                            |
 | `--cwd <path>`           | Set the working directory                                           |
 | `--no-script`            | Run the type checker even if the project has a `check` script       |

docs/snippets/cli/lint.mdx

@@ -74,6 +74,10 @@ bun lint [flags] [files, directories, or globs]
   Report errors only
 </ParamField>
 
+<ParamField path="--verbose" type="boolean">
+  Print every note, also in a run that passes
+</ParamField>
+
 <ParamField path="--max-warnings" type="number">
   Exit with code 1 if there are more warnings than this
 </ParamField>

docs/typescript-6.mdx

@@ -80,4 +80,4 @@ Yes. TypeScript 7 carries forward the same default. If you're upgrading directly
 
 ## Does this apply to `bun check`?
 
-Yes. [`bun check`](/runtime/check) behaves like TypeScript 7, whichever version of `typescript` you have installed. See [Coming from TypeScript 5](/runtime/check#coming-from-typescript-5) for the other defaults and options that changed.
+Yes. [`bun check`](/runtime/check) behaves like TypeScript 7.1, whichever version of `typescript` you have installed. See [Coming from TypeScript 5](/runtime/check#coming-from-typescript-5) for the other defaults and options that changed.

src/bun_core/env_var.rs

@@ -92,6 +92,8 @@ new!(pub BUN_DEBUG_QUIET_LOGS: boolean, "BUN_DEBUG_QUIET_LOGS", {});
 new!(pub BUN_DEBUG_TEST_STANDALONE_GRAPH_MAX_BYTES: unsigned, "BUN_DEBUG_TEST_STANDALONE_GRAPH_MAX_BYTES", {});
 // How long `bun check` runs before it draws its progress line (default 300), so a test can see the line on a small project.
 new!(pub BUN_DEBUG_TEST_CHECK_PROGRESS_DELAY_MS: unsigned, "BUN_DEBUG_TEST_CHECK_PROGRESS_DELAY_MS", {});
+// How long `bun check --runExternalCode` waits for a content mapper's first answer (default 5000), so a test doesn't.
+new!(pub BUN_DEBUG_TEST_CONTENT_MAPPER_TIMEOUT_MS: unsigned, "BUN_DEBUG_TEST_CONTENT_MAPPER_TIMEOUT_MS", {});
 new!(pub BUN_DEV_SERVER_TEST_RUNNER: string, "BUN_DEV_SERVER_TEST_RUNNER", {});
 // Debug-only: when set, `NumberRenamer` dumps the symbol table before
 // renaming (`src/js_printer/renamer.rs`). Presence-checked, value ignored.