Big release! 😀
Main feature is a rewrite of our custom runtime in preparation for stabilisation of native support of ESM. As part of that work require(esm) module is now supported (still requires --experimental-vm-modules like before).
In addition we now support fake timers for the recently released Temporal API in Node v26.
React 19 is also supported properly in pretty-format, meaning snapshots of React components now work like they should.
Full list of changes below
Features
[babel-jest]Support collecting coverage from.mts,.cts(and other) files (#15994)[jest-circus, jest-cli, jest-config, jest-core, jest-jasmine2, jest-types]Add--collect-testsflag to discover and list tests without executing them (#16006)[jest-config, jest-runner, jest-worker]AddworkerGracefulExitTimeoutconfig option to control how long workers are given to exit before being force-killed (#15984)[jest-config]Add support forjest.config.mtsas a valid configuration file (#16005)[jest-config, jest-core, jest-reporters, jest-runner]verboseandsilentcan now be set per-project; the project-level value overrides the global value for that project's tests (#16133)[@jest/fake-timers]AcceptTemporal.Durationinjest.advanceTimersByTime()andjest.advanceTimersByTimeAsync()(#16128)[@jest/fake-timers]AcceptTemporal.InstantandTemporal.ZonedDateTimeinjest.setSystemTime()anduseFakeTimers({now})(#16128)[@jest/fake-timers]Support fakingTemporal.Now.*(#16131)[jest-mock]AddclearMocksOnScope(scope)onModuleMockerfor clearing every mock function exposed on a scope object (#16088)[jest-resolve]AddcanResolveSync()onResolverso callers can detect when a user-configured resolver only exports anasynchook (#16064)[jest-runtime]Use synchronousevaluate()for ES modules without top-levelawaiton Node versions that support it (v24.9+), and prefer the synchronous transform path when a sync transformer is configured (#16062)[jest-runtime]Supportrequire()of ES modules on Node v24.9+ (#16074)[jest-runtime]Validate TC39 import attributes (with { type: 'json' }) on ESM imports (#16127)[@jest/transform]AddcanTransformSync(filename)onScriptTransformerso callers can pick the sync vs async transform path (#16062)[jest-util]AddisErrorhelper (#16076)[pretty-format]Support React 19 (#16123)
Fixes
[expect-utils]FixtoStrictEqualfailing onstructuredCloneresults due to cross-realm constructor mismatch (#15959)[@jest/expect-utils]PreventtoMatchObject/subset matching from throwing when encountering exotic iterables (#15952)[fake-timers]ConvertDateto milliseconds before passing to@sinonjs/fake-timers(#16029)[jest]ExportGlobalConfigandProjectConfigTypeScript types (#16132)[jest-circus]Prevent crash whenasyncErroris undefined for non-Error throws (#16003)[jest-circus, jest-jasmine2]IncludeError.causein JSONfailureMessagesoutput (#15967)[jest-config]Fix preset path resolution on Windows when the preset uses subpathexports(#15961)[jest-config]AllowcollectCoverageandcoverageProviderin project config without a validation warning (#16132)[jest-config]Project config validator now emits "is not supported in an individual project configuration" instead of "probably a typing mistake" for known global-only options (#16132)[jest-environment-node]Fix--localstorage-filewarning on Node 25+ (#16086)[jest-reporters]Apply global coverage threshold to unmatched pattern files in addition to glob/path thresholds (#16137)[jest-reporters, jest-runner, jest-runtime, jest-transform]Fix coverage report not showing correct code coverage when usingprojectsconfig option (#16140)[jest-runtime]Resolveexpectand@jest/expectfrom the internal module registry so test-file imports share the sameJestAssertionErroras the globalexpect(#16130)[jest-runtime]Improve CJS-from-ESM interop:__esModule/Babel default unwrap, broader named-export coverage, and shared CJS singleton across importers (#16050)[jest-runtime]Load.jsfiles with ESM syntax but no"type":"module"marker as native ESM (#16050)[jest-runtime]Extend the.js-with-ESM-syntax fallback torequire()on Node v24.9+ - falls back torequire(esm)when the CJS parser rejects ESM syntax (#16078)[jest-runtime]Fix deadlocks and double-evaluation in concurrent ESM and wasm imports (#16050)[jest-runtime]Fix error whenrequire()is called after the Jest environment has been torn down (#15951)[jest-runtime]Fix missing error whenimport()is called after the Jest environment has been torn down (#16080)[jest-runtime]Fix virtualunstable_mockModuleregistrations not respected in ESM (#16081)[jest-runtime]ApplymoduleNameMapperwhen resolving modules withrequire.resolve()and thepathsoption (#16135)
Chore & Maintenance
[@jest/fake-timers]Upgrade@sinonjs/fake-timers(#16139)[jest-runtime]Use synchronouslinkRequests/instantiatefor ESM linking on Node v24.9+ (#16063)
New Contributors
- @alexander-turner made their first contribution in #16006
- @jmuransky made their first contribution in #16050
- @afiiif made their first contribution in #16047
- @JamieMagee made their first contribution in #15959
- @Gdhanush-13 made their first contribution in #16029
- @ashoknarayan made their first contribution in #16003
- @domarmstrong made their first contribution in #15994
- @ragini-pandey made their first contribution in #15951
- @manthansubhash01 made their first contribution in #16005
- @cedricherzog-passbolt made their first contribution in #16021
- @jcwatson11 made their first contribution in #15984
- @umeshmore45 made their first contribution in #15961
- @mhughes2012 made their first contribution in #15952
- @kimsuyeon0916 made their first contribution in #16135
Full Changelog: v30.3.0...v30.4.0