Vitest Release Notes

🐞 Bug Fixes

Revive global concurrency limit for test lifecycle [backport to v4] - by @sheremet-va and @hi-ogawa in #10992 (5146d)

browser:

Encode iframeId in tester iframe URL [backport to v4] - by @sheremet-va, Pduhard and Claude Opus 4.8 in #10955 (10b2c)

Trigger playwright/chromium gc on lower disk availability [backport to v4] - by @hi-ogawa, Hiroshi Ogawa and OpenCode in #10951 (9851d)

mocker:

Restrict redirect mocks to the fs allowlist [backport to v4] - by @sheremet-va in #10974 (fe5a1)

View changes on GitHub

🚀 Features

reporter: Add custom GitHub Actions summary title - by @heyJonBray and @macarie in #10891 (4363c)

🐞 Bug Fixes

Revive global concurrency limit for test lifecycle - by @hi-ogawa, Hiroshi Ogawa, OpenCode (claude-opus-4-8) and @sheremet-va in #10928 (cf917)

Own the post-restart rerun, keep process.exit disabled in workers - by @sheremet-va in #10963 (5e69a)

Preserve correct root during resolve config - by @AriPerkkio and @sheremet-va in #10909 (210ba)

browser:

Trigger playwright/chromium gc on lower disk availability - by @hi-ogawa, Hiroshi Ogawa and OpenCode (claude-opus-4-8) in #10912 (032d3)

Disallow filter-only options in getBy* locators - by @arjun2075 in #10295 and #10933 (9b4df)

Fail instead of hanging when the browser stops responding - by @sheremet-va in #10956 (c496c)

Exit gracefully when the browser disconnects during cancellation - by @sheremet-va in #10962 (67e84)

Don't redirect vitest in client environment - by @sheremet-va in #10975 (aeb67)

deps:

Update all non-major dependencies - in #10966 (65263)

mocker:

Restrict redirect mocks to the fs allowlist - by @sheremet-va in #10972 (8ff9b)

pool:

Worker init to handle queued synchronous messages - by @lazerg and @AriPerkkio in #10932 (76096)

Report the worker exit instead of a pipe error that raced it - by @sheremet-va in #10964 (59a03)

reporters:

Display test.name in GitHub Actions reporter summary header - by @macarie in #10887 (49e24)

snapshot:

Support no-unsafe-eval CSP by evaluating snapshot files on server - by @hi-ogawa in #10665 (667c1)

ui:

Fix code editor error and annotations gadgets layout shifts - by @hi-ogawa, Hiroshi Ogawa and OpenCode (claude-opus-4-8) in #10969 (438ed)

Synchronize watch-run UI state on file removal - by @hi-ogawa, Hiroshi Ogawa and OpenCode (claude-opus-4-8) in #10941 (30c21)

Require auth for coverage report and all UI subtree requests - by @sheremet-va in #10971 (5622f)

utils:

Don't crash on a malformed inline source map - by @lazerg, Hiroshi Ogawa, OpenCode (claude-opus-4-8) and @hi-ogawa in #10892 and #10893 (fe790)

vitest:

Render non-Error causes from env setup so the actual diagnostic is not dropped - by @spokodev in #10567 (b298d)

View changes on GitHub

🚨 Breaking Changes

Inline projects extend the root config by default - by @sheremet-va in #10750 (fec00)

Enable mocking Temporal without fake timers - by @fabon-f, Hiroshi Ogawa and OpenCode in #10757 (ac2d4)

Support nested projects - by @sheremet-va in #10846 (ec367)

Use > as separator in -t, calculate only once - by @sheremet-va in #10686 (a0b20)

Fail the test when an asynchronous assertion is not awaited - by @sheremet-va in #10868 (86d4a)

Share the Vite server between inline projects - by @sheremet-va in #10848 (d87c9)

browser: Save failure screenshots in attachmentsDir - by @macarie in #10917 (3b5bb)

spy: Preserve class mock prototype methods on instances - by @sheremet-va in #10910 (6093d)

types: Add better promise support in expects and matchers - by @samchungy and @sheremet-va in #8266 (41f55)

🚀 Features

Report the duration breakdown as percentages - by @sheremet-va and @AriPerkkio in #10820 (c67d2)

cli: Support -p shorthand for --project - by @sheremet-va in #10826 (1addd)

vm: Support require(esm) in vm pools - by @sheremet-va in #10829 (01298)

🐞 Bug Fixes

Coalesce concurrent watch-mode restarts, deflake the pool stderr fixture - by @sheremet-va in #10822 (a31f8)

Prevent vitest --typecheck from reporting a false success when the tsc process crashes - by @hitenkalda and Hiten Kalda in #10705 (a1b05)

Collect in-source tests when the module is cached - by @koutaro-masaki in #10577 and #10589 (a7bf2)

Swap replace() arguments so timeout error stack shows the real message - by @lazerg in #10875 (aba0f)

Stale mock metadata breaks automocking with isolate:false - by @kade-robertson in #10145 and #10541 (8e210)

Don't lose worker output on teardown, deflake timing-sensitive tests - by @sheremet-va in #10842 (1216b)

browser:

Ignore channel events in a tester opened as a top-level window - by @simshanith in #9379 and #9381 (46a3c)

Resolve connectTimeout from the project config - by @lazerg in #10879 and #10880 (62c79)

Prebundle vite module runner with vitest - by @lebovvskii and @sheremet-va in #10836 and #10856 (37c24)

Restore dependency reload warning - by @hi-ogawa, Hiroshi Ogawa and OpenCode in #10913 (90d69)

Configure internal optimizer dependencies - by @hi-ogawa, Hiroshi Ogawa and OpenCode in #10915 (a72f4)

cache:

Improve fsModuleCache resiliency during external modifications - by @jszumski in #10869 (5eb35)

cli:

Exit on CTRL+c even when globalSetup runs blocked code - by @AriPerkkio in #10863 (d568f)

deps:

Update all non-major dependencies - by @sheremet-va in #9958 (7faa7)

Update all non-major dependencies - by @sheremet-va in #10861 (0188c)

Update all non-major dependencies - by @sheremet-va in #10898 (61c4b)

expect:

Handle nullish toHaveProperty values - by @liyimil in #10735 and #10811 (99e59)

reporters:

Print parent describe suites when the passed-test list is hidden - by @ChihebBENCHEIKH1, Chiheb Bencheikh and @sheremet-va in #10606 and #10768 (658af)

runner:

Don't fail collection when accessing error.stack throws - by @sheremet-va in #10839 (202e2)

spy:

Point ESM namespace spy error to module mocking docs - by @ryandiginomad and Ryan Tang in #10707 (d6cec)

typecheck:

Report a checker crash on Windows instead of a spawn failure - by @sheremet-va in #10907 (77aac)

vitest:

Remove broken "./src/*" export from package.json - by @sheremet-va in #10918 (2e5df)

vm:

Stop retaining every finished test file in vm pool workers - by @sheremet-va in #10854 (38503)

🏎 Performance

Lowers peak memory usage when using --changed on a large graph - by @jszumski in #10866 (9f23f)

browser: Serve framework assets as immutable - by @sheremet-va in #10729 (7af87)

View changes on GitHub

🚨 Breaking Changes

Separate config resolution from the server creation - by @sheremet-va in #10554 (1c0ec)

🚀 Features

Add toggable injectCjsGlobals option - by @sheremet-va in #10709 (82671)

Promote fsModuleCache to a top-level option - by @sheremet-va in #10734 (78ed7)

Support non-ascii characters in for/each title placeholders - by @k-yle in #10773 (15e0a)

benchmark: Add pluggable benchmark provider API - by @GuillaumeLagrange and @sheremet-va in #10799 (86c70)

🐞 Bug Fixes

Disable server HMR before plugins read it in their config hook - by @sheremet-va in #10731 (e060b)

Close the pool before the Vite servers - by @sheremet-va in #10725 (96fa6)

Remove listeners in the typecheck worker's off - by @sheremet-va in #10741 (d758b)

Keep per-file isolation in vm pools when maxWorkers is 1 - by @sheremet-va in #10743 (83ab9)

Node.js 20 deprecation warning for ci.yml - by @hirehamir in #10759 (2127f)

Prevent node builtins double prefix - by @malobre in #10630 and #10767 (22d35)

Set non-zero exit code when teardown throws during close - by @zakcutner and @AriPerkkio in #10794 (22116)

Don't race the typechecker spawn grace period on windows - by @xevrion in #10814 (b19e5)

browser:

Preserve pre-transform request defaults - by @sheremet-va in #10748 (b6060)

Fix error stacktrace location off-by-one - by @hi-ogawa, Hiroshi Ogawa and OpenCode in #10724 (62b8d)

Inlined awaited import should not trigger syntax error after transform - by @smeng9, Shaoyu Meng and Claude Opus 4.8 (1M context) in #10784 (51acd)

Mock window.print to avoid hanging - by @aaravjaichand in #7375 and #10798 (66d95)

pool:

Vm pools to respect cgroupsv2 memory limit - by @milas in #10721 (3923c)

🏎 Performance

Serve warm modules to workers in one round-trip, enable the node compile cache - by @sheremet-va in #10708 (b144a)

Make the Node compile cache opt-in, persist worker caches on teardown - by @sheremet-va in #10742 (941bc)

Reuse compiled code across vm pool contexts and prewarm the module graph - by @sheremet-va in #10744 (d8b04)

Bundle vitest's own dependencies - by @sheremet-va in #10685 (c0508)

browser:

Open browser sessions adaptively instead of maxWorkers upfront - by @sheremet-va in #10726 (6db8d)

Cut per-file round trips - by @sheremet-va in #10730 (3feef)

Stop serving framework sourcemaps in headless runs - by @sheremet-va in #10728 (6aefb)

Prewarm the browser while the Vite server starts - by @sheremet-va in #10727 (c1767)

Pre-bundle the vitest runtime in optimizeDeps - by @sheremet-va in #10713 (de631)

coverage:

Speed up v8 report generation (bounded-memory merge + precompiled globs) - by @toxik, Claude Opus 4.8 (1M context) and @AriPerkkio in #10506 (b05e5)

Reduce RPC data and unnecessary serializations - by @AriPerkkio in #10781 (7e7e3)

View changes on GitHub

🚨 Breaking Changes

Add screenshotDirectory config to browser.expect.toMatchScreenshot - by @macarie in #10592 (a60de)

Update @sinonjs/fake-timers and support mocking Temporal - by @hi-ogawa, Hiroshi Ogawa and OpenCode (claude-opus-4-8) in #10654 (f8b15)

Remove webdriverio package - by @sheremet-va in #10675 (5fed6)

Clear mocks by default before each test - by @sheremet-va in #10613 (0f646)

Don't emit localStorage warnings on Node 26, fail gracefully when worker fails to start - by @sheremet-va in #10293 (334ed)

reporters:

Write json and junit reporter output files to .vitest by default - by @hi-ogawa, Hiroshi Ogawa, OpenCode (claude-opus-4-8) and @AriPerkkio in #10621 (58577)

ui:

Harden UI API access - by @hi-ogawa, Hiroshi Ogawa and Codex in #10583 (4c26d)

Change html reporter default output to .vitest - by @hi-ogawa and Hiroshi Ogawa in #10620 (29c36)

🚀 Features

vitest: Create vi.when() - by @macarie in #10174 (3900e)

🐞 Bug Fixes

Fix setImmediate await in detect-async-leak - by @hi-ogawa and Hiroshi Ogawa in #10608 (dd62b)

Fix per-project sequence config - by @hi-ogawa, Hiroshi Ogawa and OpenCode (claude-opus-4-8) in #10659 (40cdc)

Add handshake timeout to iframe communication - by @sheremet-va in #10656 (3545f)

Don't print column in test names when includeTaskLocation is enabled - by @sheremet-va in #10681 (bd9cc)

browser:

Always derive a positive locator action timeout - by @sheremet-va in #10626 (5b864)

Resize the browser ui only if it's not headless - by @sheremet-va in #10662 (b5c61)

Check fs access in builtin commands - by @hi-ogawa, Hiroshi Ogawa and OpenCode (claude-opus-4-8) in #10674 (33f96)

coverage:

Non-awaited module imports cause wrong offsets - by @AriPerkkio in #10643 (c4090)

Fail fast when coverage.reportsDirectory conflicts between concurrent runs - by @jgamaraalv and @AriPerkkio in #10466 (833f0)

pool:

Improve error message when worker exits unexpectedly - by @filmaj and @AriPerkkio in #10587 (76139)

types:

Allow changed in configuration options - by @AriPerkkio in #10651 (0da12)

vm:

Fix external module resolve error with deps optimizer query for encoded URI - by @SveLil in #10658 (90c4e)

View changes on GitHub

🐞 Bug Fixes

Fix importOriginal with optimizer and query import [backport to v4] - by Hiroshi Ogawa, David Harris, Codexand Vladimir in #10546 (a5180)

browser:

Wait for orchestrator readiness before resolving browser sessions [backport to v4] - by Vladimir and Séamus O'Connor in #10555 (7fb29)

Wait for iframe tester readiness before preparing [backport to v4] - by Vladimir and Séamus O'Connor in #10497 and #10556 (fbc62)

mocker:

Hoist vi.mock() for vite-plus/test imports [backport to v4] - by Hiroshi Ogawa, LongYinan, Claude Opus 4.8 and Vladimir in #10548 (2c955)

pool:

Prevent test run hang on worker crash [backport to v4] - by Ari Perkkiö and Jattioui Ismail in #10543 and #10564 (934b0)

View changes on GitHub

🚨 Breaking Changes

Don't lookup config file from ancestor directories - by @hi-ogawa, Codex and Hiroshi Ogawa in #10428 (945d9)

Inline @vitest/runner package, do not publish it anymore - by @sheremet-va in #10511 (6d6e4)

Allow mutating happy-dom/jsdom window object - by @hi-ogawa, Hiroshi Ogawa and Codex in #10373 (206e8)

Expose concurrencyId/workerId on TestModule's diagnostics, make id 1-based - by @sheremet-va in #10516 (bdd98)

browser: Require sessionId for orchestrator html request - by @hi-ogawa, Hiroshi Ogawa and Codex in #10522 (79b7d)

coverage: Allow thresholds.perFile to accept an object - by @vladlenskiy and @AriPerkkio in #10190 (13b78)

🚀 Features

browser: Display nested mark trace in UI - by @hi-ogawa, Hiroshi Ogawa and Codex in #10437 (86ffc)

cli: Add --repeats CLI option - by @todor-a in #10504 (ee48b)

coverage: thresholds.autoUpdate to receive previous threshold as argument - by @wouterkroes in #10495 (04f81)

🐞 Bug Fixes

Fix mixed stdout/stderr log timestamps in onUserConsoleLog - by @Copilot, Hiroshi Ogawa, @hi-ogawa and @sheremet-va in #10308 (62756)

Fix importOriginal with optimizer and query import - by @davidhwilliams, David Harris, @hi-ogawa, Hiroshi Ogawa and Codex in #10469 (6a3bb)

Correct transform time calculation in merged report - by @potatomatoooo and @hi-ogawa in #10570 and #10578 (b7897)

browser:

Wait for orchestrator readiness before resolving browser sessions - by @soconnor-seeq in #10397 (fe5ed)

Wait for iframe tester readiness before preparing - by @soconnor-seeq in #10497 (f2655)

Encode iframeId in tester iframe URL - by @Pduhard, Pduhard and Claude Opus 4.8 (1M context) in #10520 and #10521 (c8bf1)

coverage:

Avoid matching sibling project roots - by @innoprej, Shin JaeHee and @AriPerkkio in #10311 (e30dd)

mocker:

Hoist vi.mock() for vite-plus/test imports - by @Brooooooklyn and Claude Opus 4.8 (1M context) in #10489 (88376)

pool:

Prevent test run hang on worker crash - by @jaxalo and @AriPerkkio in #10543 (40878)

vitest:

Strip non-serializable functions from inline diff config - by @DucMinhNe in #10573 (5b81a)

View changes on GitHub

🚨 Breaking Changes

Throw an error if hoistable methods are outside the top level scope - by @sheremet-va in #10460 (d0b4f)

toHaveTextContent is strict, add toMatchTextContent as alternative - by @sheremet-va in #10473 (18f30)

benchmark: Rewrite the public API - by @sheremet-va in #10113 (19f6e)

browser: Enable locators.exact by default - by @sheremet-va in #10430 (e2032)

🚀 Features

browser: Show trace view steps in editor panel - by @hi-ogawa and Codex in #10404 (8c4b6)

reporter: Support html reporter single file output - by @hi-ogawa, Codex and Claude Opus 4.7 (1M context) in #10235 (f757e)

🐞 Bug Fixes

Preserve vi.defineHelper callsite for async error stack - by @macayu17 and @hi-ogawa in #10415 (ac697)

Respect disableConsoleIntercept in browser mode - by @Copilot, hi-ogawa, @hi-ogawa and Codex in #10391 (66110)

ForceRerunTriggers uses directory globs against files - by @Patrick-Clausen and Patrick Clausen in #10421 and #10420 (4fee2)

Unify typechecking and ast collection - by @sheremet-va in #10449 (af993)

Don't print typecheck warning more than once - by @sheremet-va in #10461 (15275)

Correct collumn when parsing tests - by @sheremet-va in #10467 (7c2fc)

browser:

Fix stale source map on watch mode - by @hi-ogawa in #10389 (6d772)

Escape inline orchestrator scripts - by @hi-ogawa and Codex in #10412 (c22cf)

Disable client cdp API when allowWrite/allowExec: false - by @hi-ogawa and Codex in #10444 (63e3b)

mocker:

Skip hoist transform without ast mock calls - by @hi-ogawa and Codex in #10410 (0468e)

ui:

Fix module graph in browser mode with --ui - by @hi-ogawa in #10386 (3003c)

Render ANSI color codes in editor panel inline error widget - by @Copilot, hi-ogawa and @hi-ogawa in #10418 (766b8)

webdriverio:

Allow gpu in headless chrome - by @rotempasharel1 in #10376 (f310a)

🏎 Performance

Improve performance in hot paths - by @sheremet-va in #10446 (03faf)

View changes on GitHub

Breaking Changes

Require Node.js 22 and Vite 6.4 - by @sheremet-va in #10178 (38762)

Fail expect.poll when function didn't resolve in time - by @hi-ogawa and Codex in #10233 (4df04)

Features

Support typescript build mode - by @lishaduck in #9870 (106da)

api:

Expose logs recorded during the test - by @sheremet-va in #10277 (cba20)

browser:

Show aria tree on locator element error - by @hi-ogawa and Codex in #10257 (04f04)

Support custom kind in page.mark - by @AriPerkkio in #10302 (053e8)

Live update trace view on watch UI - by @hi-ogawa and Codex in #10296 (78c11)

Add context.mark for custom command tracing - by @AriPerkkio in #10329 (aa514)

Bug Fixes

Shell injection safety via github.ref_name in publish workflow - by @lloyd-c137 and lloyd-c137 in #10327 (dd020)

Make attachmentsDir root only config - by @hi-ogawa and Codex in #10334 (fab1b)

Apply cjs interop for truthy __esModule - by @hi-ogawa in #10363 (2b135)

browser:

Simplify orchestrator otel carrier - by @hi-ogawa in #10283 (3514f)

Remove orphaned Playwright route when same module is mocked via multiple ids - by @Zelys-DFKH in #9957 and #10267 (41db6)

Skip wrapDynamicImport transform on ssr environment - by @hi-ogawa in #10355 (d3c96)

cli:

Respect FORCE_COLOR over agent detection - by @dokson in #10272 (7e66b)

coverage:

exclude to not inherit negation globs from test.include - by @AriPerkkio in #10299 (28685)

deps:

Update fake-timers to 15.3.2. support toNotFake - by @BPScott, @hi-ogawa and Codex in #10043 (bbf2f)

expect:

Allow readonly arrays and sets in toBeOneOf - by @YBJ0000 in #10264 and #10374 (fed11)

junit:

Include unhandled errors in JUnit XML report - by @gbleu and Claude Sonnet 4.6 in #10244 (6f74e)

reporter:

Guard against non-finite slowTestThreshold in summary reporter - by @OfekDanny, Ofek Danny, Claude Sonnet 4.6 and @AriPerkkio in #10202 (f362f)

Fix non-existing import subpath module blob serialization - by @hi-ogawa in #10318 (29cb0)

reporters:

Fix blob file name with label - by @hi-ogawa in #10346 (c5e2e)

summary to intercept logger's streams even when they are not process.std* streams - by @AriPerkkio in #10340 (f79e7)

Fix missing testModules in onTestRunEnd when merging blobs from different root directory test runs - by @hi-ogawa and Codex in #10348 (745b3)

runner:

Remove AbortSignal listener leak in withCancel - by @tomohiro86 and @AriPerkkio in #10265 (ab098)

ui:

Fix duplicate colored error message - by @hi-ogawa and Codex in #10258 (035e3)

Fix missing source code in html reporter metadata when merging blobs with different root directory test runs - by @hi-ogawa and Codex in #10338 (4f7c2)

Performance

Stringify diff objects only once - by @sheremet-va in #10276 (d006a)

browser: Reduce matching screenshot overhead - by @kasperpeulen in #10278 (511c0)

View changes on GitHub