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Updated 7:34 AM PT - Sep 18th, 2026
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Included review availability: Your plan provides up to 10 included reviews per hour; 1 remains after this review. WalkthroughChangesModule loading removes failed entries that never evaluated, tracks pending loads until settlement, and shares resolved-key handling across imports and synchronous loads. Module Load Failure Retry
Suggested reviewers: Priority: ⬇️ Low Merge Risk: 🟡 Moderate · up to A failed typed module load can remain permanently cached when another variant succeeds, defeating the retry behavior this change intends to provide. Resolve this before merge. 🚥 Pre-merge checks | ✅ 4✅ Passed checks (4 passed)
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Beyond the inline findings, I also checked that attaching onSettled as both fulfill and reject handlers on the import() promise does not swallow unhandledRejection (the reaction is on the outer promise, and performPromiseThenWithContext returns a new promise whose rejection is the one tracked), and that performPromiseThenWithContext after importModule needs no exception check (it takes vm and does not throw).
Extended reasoning...
Two candidate issues were raised by finder agents and refuted on closer inspection: (1) whether adding a reject handler to the import() promise suppresses unhandledRejection — it does not, because JSC's rejection tracker fires on the promise returned to user code, and the internal then() creates a separate capability; (2) whether a missing RETURN_IF_EXCEPTION after performPromiseThenWithContext could leak the pendingDynamicImports count — performPromiseThenWithContext takes a VM& and does not enter user JS or throw, so no scope check is needed there. Recording these so a later pass does not re-derive them.
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| // The JSC loader caches every failure, including a transpile error, an | ||
| // unresolved static import, or a link error. That is the browser behavior | ||
| // (a module script that fails to fetch or parse is cached as null). Node never | ||
| // caches those: its ModuleJob is only added to the load cache once the source | ||
| // compiled and every dependency resolved, so the next import() re-reads the | ||
| // file. A module that never started evaluating has no side effects that a | ||
| // second load could duplicate, so drop the stale record and let the loader | ||
| // fetch again. A module whose body threw stays cached, as in Node and the spec. |
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| // A dependency that failed to load is stored as an evaluation error on | ||
| // the importer even though the importer never linked. |
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| // The map is keyed by (specifier, type). Probe each type directly: | ||
| // registryEntry() falls back to a scan of the whole map for a key that has | ||
| // no JavaScript entry, and this runs on every resolve. |
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| // A top-level load of this key is still settling. The loader records a | ||
| // top-level failure in one microtask and reports it in the next, and the | ||
| // second one looks the key up by name: it would attach the stale error to | ||
| // any entry a new fetch registered in between. Keep the failed entry until | ||
| // the load's promise has settled. |
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| // removeEntry drops every type variant of the key, so keep them all | ||
| // while any variant holds a module that may have run. |
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| // JSModuleLoader::visitChildrenImpl iterates these maps on the GC thread | ||
| // under cellLock(); take the same lock so the removal can't race it. |
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| // Reaction on the promise of a top-level module load: argument 1 is the | ||
| // resolved key that trackPendingModuleLoad registered in pendingModuleLoads. |
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| // The key string shares the Identifier's atom, so the handler gets the same | ||
| // UniquedStringImpl back from Identifier::fromString. |
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| // import() of an already resolved key. The key stays in pendingModuleLoads | ||
| // until the returned promise settles, which is after the loader has finished | ||
| // touching the registry for this load. See dropFailedEntryThatNeverEvaluated. |
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| // A load that was in flight has lost its entry, so its promise may never | ||
| // settle. Do not let it pin a failed entry of the next registry. |
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| // Every lookup of a module in the registry, whether from import(), a | ||
| // static import of a module being linked, or the entry point, goes through | ||
| // resolve() first. Evicting here makes the loader fetch the module again | ||
| // when its last load never produced a module. |
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| // Resolved keys of the top-level module loads (import(), Module.runMain) | ||
| // whose promise has not settled yet. moduleLoaderResolve must not drop a | ||
| // failed registry entry for such a key: the loader's ModuleLoadTopRejected | ||
| // microtask still looks the key up by name after the failure is recorded, | ||
| // and would store the stale error on a fresh entry. |
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| // Keeps `key` in pendingModuleLoads until `promise`, the result of a | ||
| // top-level load of that key, settles. |
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| // Resolve first: the load is a top-level load like import() and is tracked | ||
| // under the key the loader uses while its promise is pending. |
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| // Like Node, re-fetch a module whose load failed before it ran; only a module | ||
| // whose body threw keeps its error (the spec's [[EvaluationError]]). |
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| // Probe each (specifier, type) bucket: registryEntry() scans the whole map | ||
| // for a key without a JavaScript entry, and this runs on every resolve. |
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| // ModuleLoadTopRejected looks the key up by name one microtask after the | ||
| // failure is recorded; a fresh entry there would inherit the stale error. |
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| // Every registry lookup, for import(), a static import, or the entry point, | ||
| // resolves first, so this is where a failed load is retried. |
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| // Resolved keys of the top-level module loads (import(), Module.runMain) | ||
| // whose promise has not settled; moduleLoaderResolve keeps their failed | ||
| // registry entries until then. |
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Inline comments:
In `@src/jsc/bindings/ZigGlobalObject.cpp`:
- Around line 3559-3576: Update the module loading flow around
moduleLoaderResolve and moduleLoadStoreError to retain dependency keys until
failure recording completes, preventing a same-tick retry from being poisoned by
an older failure. Ensure the tracking is cleared when moduleLoadStoreError
finishes, and add a regression test covering a parent-to-dependency (P → D) load
and retry.
In `@test/js/bun/resolve/import-retry-after-failure.test.ts`:
- Line 144: Update the stderr assertion in the retry test to trim or otherwise
normalize stderr before comparing it with an empty string, while preserving the
existing assertion intent.
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I reviewed this PR and the bug-hunting pass found no issues. My earlier inline comments (clearing pendingModuleLoads on registry reset, and H3 coverage for the Module.runMain sibling) have both been addressed. Given this touches the module-loader hot path, adds per-load state on ZigGlobalObject, and the description itself notes a loader-side alternative in the WebKit fork would remove the guard, a maintainer look at the design choice is still warranted.
What was reviewed:
- Eviction predicate vs.
CyclicModuleRecord::Status— a body-throw (Evaluated+evaluationError) is kept, matching Node/spec (test E2). pendingModuleLoadsguard against theModuleLoadTopSettled→ModuleLoadTopRejectedwindow; verified it does not swallowunhandledRejection(the reaction runs after JSC has already tracked the rejection).removeEntryundercellLock()matches the existingrequire.cachedelete path; the six-bucket probe avoids the whole-map scanregistryEntry()would do per resolve.
Extended reasoning...
Overview
Re-fetches a module whose previous load failed before its body ran, so a fixed file on disk is picked up on the next import() — matching Node's behavior where only a module whose body threw stays cached. Touches ZigGlobalObject.cpp/.h (~130 new lines: isFailedEntryThatNeverEvaluated, dropFailedEntryThatNeverEvaluated, trackPendingModuleLoad, importResolvedModule, and a split of moduleLoaderResolve into resolveModuleKey + a wrapper that evicts), NodeModuleModule.cpp (jsFunctionRunMain now resolves first and tracks its load), and a new 160-line subprocess test with 12 labeled cases.
Security risks
None identified. The change re-reads files the process already had permission to read; it does not widen resolution scope or accept new untrusted input. The HashCountedSet key is a RefPtr<UniquedStringImpl> (owning), so no lifetime issue from storing an Identifier's atom. No auth/crypto/permissions surface.
Level of scrutiny
High. moduleLoaderResolve runs on every module resolution — import(), static imports, and entry points — so dropFailedEntryThatNeverEvaluated is now on the hot path (mitigated by probing six map buckets directly rather than scanning). The guard's correctness depends on JSC-internal microtask ordering (ModuleLoadTopSettled → ModuleLoadTopRejected → user .then), which is fragile across WebKit bumps. REVIEW.md's architecture guidance discourages new fields on ZigGlobalObject, and the PR description explicitly names a loader-side alternative in oven-sh/WebKit that would remove the pendingModuleLoads guard entirely — that design tradeoff (Bun-side workaround now vs. WebKit change + version bump) is a maintainer call.
Other factors
All prior review threads (mine, CodeRabbit's) are resolved and reflected in the current diff: clearModuleRegistry() clears the set, jsFunctionRunMain tracks its load, H3 covers the runMain race, stderr is trimmed. Verifier agents ruled out the unhandledRejection-suppression concern (the settle handler is a regular reaction, so the rejection is already tracked before it runs). The comment-cop bot flagged several multi-line comments; commit 2f7c2bb shortened them but a few remain — cosmetic, not blocking. Test coverage is thorough (own syntax error, missing/bad static dep, dep-first-then-parent, require(esm), plugin onLoad, three concurrency shapes, body-throw stays cached) and the description reports it fails on release bun as required.
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| // Reaction on a tracked load's promise. Argument 1 is the resolved key passed | ||
| // by trackPendingModuleLoad. |
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| // A load of this key is in flight: join it, as Node shares the in-flight | ||
| // job. A second top-level load would fetch again, and the loader reports | ||
| // the first load's failure by key one microtask later, onto whatever entry | ||
| // the second load registered in between. |
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Reviewed 9b4f9d0 and found no new issues — the two blockers from my last pass are addressed. Given eight iterations on module-loader concurrency semantics, a human sign-off is still worthwhile.
What was reviewed:
PendingModuleLoadKeynow carriesScriptFetchParameters::TypeandimportResolvedModulekeys the join on it; test D (./d.jsonvswith { type: "text" }in one tick) pins this.jsFunctionRunMaintracks a derivednamespacePromise(viaBun__moduleNamespaceForKey,jsUndefined()pass-through on rejection per the establishedperformPromiseThenWithContextpattern) so a joiningimport()fulfills with the namespace; H5 covers success, H3 covers rejection.Bun__onModuleLoadSettlediterates all type buckets and only removes settled entries, so a newer runMain load of the same key stays pending;hasPendingModuleLoadlikewise checks all types before eviction, matchingremoveEntry's all-variant drop.- The pre-existing "one live type variant blocks retry of a failed sibling variant" limitation I noted is now called out in the PR description as intentionally kept on-par with main.
Extended reasoning...
Overview
Commit 9b4f9d0 responds to the two red findings from the 2026-08-27 review. First, pendingModuleLoads is now a WeakGCMap<PendingModuleLoadKey, JSPromise> where the key is (RefPtr<UniquedStringImpl>, ScriptFetchParameters::Type) — importResolvedModule computes the type from parameters and both the join lookup and trackPendingModuleLoad use it, so a same-tick import("./d.json") and import("./d.json", { with: { type: "text" } }) no longer share a load. Second, jsFunctionRunMain no longer tracks the raw loadAndEvaluateModule promise; it resolves the specifier through moduleLoaderResolve, creates a namespacePromise, chains Bun__moduleNamespaceForKey as the fulfillment handler on the load promise (with jsUndefined() as onRejected so a rejection passes through), marks it handled to avoid a duplicate unhandled-rejection report alongside the VM's own reporting on the original promise, and tracks that. An import() that joins a runMain load now pipeFroms a promise that fulfills with the module namespace. New tests H5 (successful runMain join yields ns.v === 42) and D (typed vs untyped JSON import in one tick yields object vs string) pin both fixes; H3 already covers the rejection path.
Security risks
None identified. The change alters when the module loader retries a failed fetch and how concurrent top-level loads of the same key are coalesced. It does not touch auth, crypto, network trust boundaries, or untrusted-input parsing beyond what the existing loader already handled. The WeakGCMap and cellLock() usage follow the loader's existing patterns for GC-safe registry mutation.
Level of scrutiny
High. This is C++ in the JSC module-loader hot path with subtle microtask-ordering invariants (ModuleLoadTopRejected reporting one microtask after the failure, the join preventing a second fetch from inheriting the first's key-based error). It has been through eight review iterations, each surfacing a real correctness gap; that history alone argues for a maintainer's read of the final shape rather than automated approval. REVIEW.md's "no new fields on ZigGlobalObject" is nominally in tension with pendingModuleLoads, though the state is genuinely per-VM and lifetime-tied to moduleLoader() — a human should confirm the placement is acceptable.
Other factors
performPromiseThenWithContext is on the nothrow list and the jsUndefined()-as-onRejected pass-through pattern matches existing call sites in the streams bindings, so the lack of an exception check between performPromiseThenWithContext and trackPendingModuleLoad in jsFunctionRunMain is consistent with the codebase. Bun__onModuleLoadSettled scans all six type buckets rather than the one it was tracked under because the context carries only the key string; it removes only entries whose promise is no longer Pending, which correctly preserves a newer in-flight runMain load of the same key. clearModuleRegistry() clears pendingModuleLoads (from an earlier iteration). The test file asserts stdout via inline snapshot before checking stderr.trim() and exitCode, per the harness conventions. The PR description reports 179/181 CI lanes green with the two failures being pre-existing infra/main breaks.
The JSC module loader keeps every failed ModuleRegistryEntry and replays its error on the next lookup of the key. A syntax error, a static import that did not resolve, a link error, or a plugin onLoad that returned unparseable code therefore stayed failed for the whole process, even after the file on disk was fixed. Node never caches a module that failed to load, so the next import() re-reads the file. moduleLoaderResolve and the require(esm) path now drop an entry whose status is FetchFailed, InstantiationFailed, or EvaluationFailed with a record that never reached Evaluating. The loader then fetches the module again. removeEntry also clears the cached resolution failures of the module, so a dependency created later is found. A module whose body threw stays cached, as in Node and the spec. The eviction is skipped while an import() of the same key has not settled. The loader records a top-level failure in ModuleLoadTopSettled and reports it one microtask later in ModuleLoadTopRejected, which looks the key up by name again. A fetch registered in that window would inherit the stale error, and the debug build asserts in ModuleRegistryEntry::fetchComplete. The global object counts the pending import() calls per resolved key and removes the key when the import promise settles.
Module.runMain starts a top-level load like import() does, so a failed entry of that key must stay put until its promise settles. Resolve the specifier first and register the load under the same key. clearModuleRegistry drops every entry, so a load that was in flight may never settle. Clear the pending set with the registry, or that key would keep its next failed entry forever.
…nd load Since WebKit 8c4fd56347 a top-level load registers its entry only once the fetch succeeds, and ModuleLoadTopRejected records a failure by key one microtask after it happened. Two import() calls of one failing module in the same tick made the second load's fresh entry inherit the first load's error: the module failed for the rest of the process in release builds, and fetchComplete's status assertion fired in debug builds. Keep the in-flight promise per key in a WeakGCMap and hand a second import() a promise piped from it, as Node shares the in-flight job.
…its namespace
A second import() joined any in-flight load of the same key. The loader's
registry is keyed by (key, type), so import("./d.json") and
import("./d.json", { with: { type: "text" } }) in one tick gave the second
the first one's module. Key the pending loads the same way, and keep a
failed entry while a load of any type of the key is pending.
The promise loadAndEvaluateModule returns for Module.runMain settles with
the evaluation result. An import() that joined it got that value instead
of the namespace. Track a derived promise that fulfills with the key's
namespace, marked handled because the VM reports a rejection through the
original one.
…utcome Eight import() calls of a module whose fetches 2 to 8 would fail (a file caught mid-save): with the join there is one plugin load, one namespace for all eight, and the next import() returns it. Without it, main gives OK then seven errors, and the key stays poisoned.
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Inline comments:
In `@src/jsc/bindings/ZigGlobalObject.cpp`:
- Around line 788-789: Update the failed-entry eviction logic in the function
containing isFailedEntryThatNeverEvaluated so it evaluates and removes each
failed (key, type) variant even when a sibling variant succeeds, while
preserving successful cached variants. Add a regression test covering a
successful text import followed by a JSON retry after repairing the source.
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Inline comments:
In `@src/jsc/modules/NodeModuleModule.cpp`:
- Line 800: Update jsFunctionRunMain to register and reuse the pending namespace
promise before starting another load, so repeated same-key Module.runMain calls
join the existing load. Keep the loader’s evaluation-result promise in
VirtualMachine::pending_internal_promise via setOverrideModuleRunMainPromise,
while trackPendingModuleLoad uses the namespace promise only for joining.
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A second runMain of the key, or a runMain after an import() of it that has not settled, started another top-level load. It now joins the pending one, as import() does.
| // A load of this key is in flight, from import() or an earlier runMain: join | ||
| // it, for the reason importResolvedModule does. |
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If you need a paragraph-long comment to justify why the workaround is OK, the code is wrong — fix the code
main added Bun.ModuleGraph: a global object now has one module loader per graph, and the loader hooks receive the loader. The retry and the join act on the loader they are given, and only when it is the global object's own loader, whose pending loads are the ones tracked. A Bun.ModuleGraph loader keeps the loader's default behavior. A pending load is now read from the promise status. The loader settles the promise after it has recorded a failure, so the settle reaction is gone.
The GC prunes a WeakGCMap in its end phase, where JSC clears the thread's atom table. A key of this map owns a ref of the module key atom. When that ref is the last one, the prune destroys the atom, and AtomStringImpl::remove reads the null table: SEGV under Heap::pruneStaleEntriesFromWeakGCHashTables. A top-level load whose own fetch fails registers no entry, so the map's ref is often the last one. Use a HashMap of Weak handles. trackPendingModuleLoad prunes the settled and the collected ones on the JS thread, at a size that doubles.
| // The retry, and the join in importResolvedModule, cover the global object's own | ||
| // loader. Pending loads are per loader and only that loader's are tracked, so a | ||
| // Bun.ModuleGraph loader keeps the loader's default behavior. |
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| // A load of this key is in flight: join it, as Node shares the in-flight | ||
| // job. A second top-level load would fetch again, and the loader reports | ||
| // the first load's failure by key one microtask later, onto whatever entry | ||
| // the second load registered in between. |
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| // The last top-level load (import(), Module.runMain) of each (resolved key, | ||
| // module type) in moduleLoader(), keyed like its registry. Each promise | ||
| // fulfills with the module namespace. While one is pending, a second | ||
| // import() of the pair joins it and moduleLoaderResolve keeps the key's | ||
| // failed registry entries. The loader settles the promise after it has | ||
| // recorded a failure, so a settled one guards nothing. | ||
| // Not a WeakGCMap: the GC prunes those with no atom table set, and a key | ||
| // here can hold the last ref of its atom. trackPendingModuleLoad prunes. |
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Problem
import()still rejects with the stale error, for exampleCannot find module './c.mjs' imported from /tmp/b.mjsfor a static dependency created later. Node re-reads the file. Onlyimport(path + "?bust")ordelete require.cache[path]recovered.ModuleRegistryEntry, although the importer never linked.JSModuleLoader::loadModulereturns that error without calling the host.import()calls of one failing module in the same tick poison it.ModuleLoadTopRejectedreports the first load's failure by key one microtask later, onto the entry the second load registered. Release builds reject that module forever. Debug builds assertm_status == Status::FetchinginModuleRegistryEntry::fetchComplete.Fix
moduleLoaderResolveand therequire(esm)path drop a registry entry whose load failed and whose record never reachedEvaluating. The loader then fetches again. Such a module has no side effects to duplicate. A module whose body threw keeps its error, as in Node and the spec (testE2).import()of a key whose top-level load is pending joins that load, as Node shares the in-flight job. The eviction waits for the pending loads of the key. Pending loads are weak handles keyed by (resolved key, module type), as the registry is.Bun.ModuleGraphloader (Bun.ModuleGraph: a context per graph for timers and I/O, per-graph CommonJS #42590) keeps the default behavior.test/js/bun/resolve/import-retry-after-failure.test.ts(main fails B, S, H1, K, H2, H3, H6). Also the resolve, node module, plugin, module-graph, hot, test isolation, and worker suites.Background
JSModuleLoadermaps (specifier, type) to aModuleRegistryEntrywith aStatusand one error slot. A top-level load registers its entry when the fetch succeeds. A dependency load registers it first.CyclicModuleRecord::Statustells a failed dependency apart from a body that threw: the latter isEvaluatedwithevaluationError()set.removeEntryis the existing eviction API (require.cachedeletes,mock.module,bun --hot).moduleLoaderResolve.Notes
Since WebKit 8c4fd56347 (#40276) a top-level
import()whose own fetch fails registers no entry, so that face already retries on main. The entry statuses the eviction accepts areFetchFailed,InstantiationFailed, andEvaluationFailedwith a record belowEvaluating. A load is pending while its tracked promise is: the loader settles that promise afterModuleLoadTopRejectedhas recorded the failure. AModule.runMainload is tracked through a derived promise that fulfills with the namespace.Faces reproduced on bun 1.4.0 and fixed here (node v26.3.0 recovers on all of them): static dependency missing then created (the dependency itself imported in between); static dependency with a syntax error then fixed; a dependency that failed on its own
import(), fixed, then imported statically by a new parent;import()failed thenrequire()of the fixed file. A module's own syntax error (A1/A2), a.tstranspile error, and a pluginonLoadthat returned bad contents once (P1/P2) fail on 1.4.0 but pass on main since the WebKit upgrade; the test keeps them.Kept as on main and in Node: a link error ("Export named 'x' not found") stays cached while the dependency's record is
Fetched, and an evaluation error is replayed. Also kept as on main: a key with a live entry of one import attribute type keeps a failed entry of another type, becauseremoveEntrydrops every type variant and the loader has no per-variant eviction for a never-evaluated failure.The same-tick case, on main's release build:
Promise.allSettled([import("./x"), import("./x")])of a module that fails once givesERR OK, and every laterimport("./x")rejects with the first error while the plugin is never asked again. With the join both calls reject, and the nextimport()re-fetches (H1:ERR ERR,H1b OK 42, two loads). H2 and H3 cover animport()issued one microtask later and a failingModule.runMainload joined by animport(). H5 joins aModule.runMainload that succeeds and gets the namespace. H6 is twoModule.runMaincalls of one failing module followed by animport():runMainjoins a pending load of the key too, so there is one load, and the nextimport()re-fetches. J covers twoimport()calls of a module that loads: one namespace object. D coversimport("./d.json")andimport("./d.json", { with: { type: "text" } })in one tick: two loads, an object and a string.K covers eight
import()calls of a module whose fetches 2 to 8 would fail (a file caught mid-save by some of the callers): one plugin load, one namespace for all eight, and the nextimport()returns it. Main givesOKthen seven errors, and the key stays poisoned. This is the mixed-outcome shape, where one sibling fetch succeeds and another fails with ENOENT, a torn file, or a directory: on main's release build the three-caller repro poisons the key in 4 of 15 runs, on this branch 0 of 45 across the three transients. The join also makes K callers cost one fetch and one transpile: on main, K same-tickimport()calls of a 5.5 MB TypeScript module peak at 0.2 GB (K=1), 1.5 GB (K=10), and 2.1 GB (K=25) of RSS; on this branch K=1, 10, and 25 peak at the same RSS and take the same time.The pending map is a
HashMapofJSC::Weakhandles thattrackPendingModuleLoadprunes on the JS thread (settled and collected entries, at a size that doubles). A pending load's promise is reachable from its own reaction chain until it settles, so a cleared weak handle means the load can no longer report anything. Two earlier shapes did not survive.WriteBarriervalues re-marked the whole global object:import()of 300 distinct keys went from 5.5 ms to 12.1 ms each on the debug build. AWeakGCMapcrashed in the GC: JSC prunes it in the end phase with the thread's atom table cleared (Heap::runEndPhase), a key of this map owns a ref of the module key atom, and when that ref is the last oneAtomStringImpl::removereads the null table (SEGV underHeap::pruneStaleEntriesFromWeakGCHashTables, seen intest/js/bun/resolve/on a debug build). A top-level load whose own fetch fails registers no entry, so the map's ref is often the last one. That shape also removed entries from a reaction on each tracked promise; reading the promise status makes the reaction unnecessary, andimport()no longer allocates one.Bun.ModuleGraph(#42590, merged into this branch at 3435bb4) gives a global object one module loader per graph and passes the loader to the hooks.import()inside a graph loads through the graph's loader as on main. The retry and the join checkloader == globalObject->moduleLoader()because the pending loads are per loader and only the global object's own are tracked. A graph is a disposable instance of a program, so a failed load there is retried with a new graph; a per-graph pending map onJSModuleGraphis a possible follow-up. The module-graph suites pass on this branch (module-graph.test.ts292,module-graph-gc.test.ts29; inmodule-graph-isolation,-callbacks, and-matrix, the only failures on this debug build are 5 s timeouts in tests that heat JIT tiers or run under load, and they pass alone except the three heat cases, which exceed 5 s here).registryEntry(key)scans the whole map for a key with no JavaScript entry, so the helper probes the sixScriptFetchParameters::Typebuckets directly. The eviction only runs when every variant of the key is a never-evaluated failure.Rebases: after the WebKit upgrade the conflicts were in
ZigGlobalObject.cpp, where main addedisModuleEvaluatingSyncandisModuleEvaluatingnext to the helpers this PR adds; both sets are kept. Main then replaced the literalpromiseFunctionsSizewith aCount_sentinel in thePromiseFunctionsenum; the two handlers this PR adds sit before it. Main then addedStandaloneGlobalObject::moduleLoaderResolve, which hands an embedded module's/$bunfs/key straight back and otherwise callsGlobalObject::moduleLoaderResolve; that call reaches the eviction in this PR, the embedded fast path does not (an embedded module cannot change on disk). 327b7e2 was a clean rebase onto d316760 plus the K test. The branch then takes merges of main instead of rebases. In the merge at 0c4d278, main's WebKit (9b02218df6) makesremoveEntryandclearAlltake the loader'scellLock()themselves, so the eviction here no longer takes it aroundremoveEntry(it would deadlock), andimportResolvedModulecallsrequestImportModuleon the loader as main's call sites now do. Main's newisModuleLoadSettledandevaluatedModuleRecordhelpers sit next to the ones this PR adds.Suites in this debug+ASAN container:
test/js/bun/resolve/has one pre-existing timeout (load the same empty JS file 2000 times).test/js/web/workers/worker.test.tshas two timing failures here with and without this change: a worker starts in 110 ms on this build, past the 30 ms window of the message flood test, and the preload test needs 5.5 s against its 5 s default.test/cli/run/require-cache.test.tsleak tests time out here with and without the change.A loader-side fix for the same-tick case (
ModuleLoadTopRejectedusing the entry it created, not a by-name lookup) needs an oven-sh/WebKit change and aWEBKIT_VERSIONbump.CI history: at 9b4f9d0, 180 of 181 lanes passed; the red lane was debian x64 ASAN, where
test/cli/run/require-cache.test.ts("don't leak file paths via import()") times out at 30 s, which fails on main's build too and is with main-break triage. At 694464d, 179 of 181: the darwin x64 lane failed before any test ran (the runner timed out cloning theelysiavendor repo), and debian x64 ASAN failedtest/bundler/transpiler/macro-test.test.tswith a LeakSanitizer report fromnode_fs_binding::Binding, also a main break. At e592cbe the only red lane wastest/js/web/url/url.test.tson darwin x64 (TypeError: Invalid URL), also a main break.[human-review] gate passed · iteration 11 · 5 files touched
fails on main (without fix)
passes on PR (with fix)
diff hotspot
gate history · 8 passed · 1 rejected · iteration 11
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