jest-util

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 on Node 24.9+ (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.

Due to all the changes, there might be regressions that snuck in. Please report them!

Full list of changes below

Features

• babel-jest: Support collecting coverage from .mts, .cts (and other) files

• [jest-circus, jest-cli, jest-config, jest-core, jest-jasmine2, jest-types] Add --collect-tests flag to discover and list tests without executing them

• jest-config, jest-runner, jest-worker: Add workerGracefulExitTimeout config option to control how long workers are given to exit before being force-killed

• jest-config: Add support for jest.config.mts as a valid configuration file

• [jest-config, jest-core, jest-reporters, jest-runner] verbose and silent can now be set per-project; the project-level value overrides the global value for that project's tests

• @jest/fake-timers: Accept Temporal.Duration in jest.advanceTimersByTime() and jest.advanceTimersByTimeAsync()

• @jest/fake-timers: Accept Temporal.Instant and Temporal.ZonedDateTime in jest.setSystemTime() and useFakeTimers({now})

• @jest/fake-timers: Support faking Temporal.Now.*

• jest-mock: Add clearMocksOnScope(scope) on ModuleMocker for clearing every mock function exposed on a scope object

• jest-resolve: Add canResolveSync() on Resolver so callers can detect when a user-configured resolver only exports an async hook

• jest-runtime: Use synchronous evaluate() for ES modules without top-level await on Node versions that support it (v24.9+), and prefer the synchronous transform path when a sync transformer is configured

• jest-runtime: Support require() of ES modules on Node v24.9+

• jest-runtime: Validate TC39 import attributes (with { type: 'json' }) on ESM imports

• @jest/transform: Add canTransformSync(filename) on ScriptTransformer so callers can pick the sync vs async transform path

• jest-util: Add isError helper

• pretty-format: Support React 19

Fixes

• expect-utils: Fix toStrictEqual failing on structuredClone results due to cross-realm constructor mismatch

• @jest/expect-utils: Prevent toMatchObject/subset matching from throwing when encountering exotic iterables

• fake-timers: Convert Date to milliseconds before passing to @sinonjs/fake-timers

• jest: Export GlobalConfig and ProjectConfig TypeScript types

• jest-circus: Prevent crash when asyncError is undefined for non-Error throws

• jest-circus, jest-jasmine2: Include Error.cause in JSON failureMessages output

• jest-config: Fix preset path resolution on Windows when the preset uses subpath exports

• jest-config: Allow collectCoverage and coverageProvider in project config without a validation warning

• 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

• jest-environment-node: Fix --localstorage-file warning on Node 25+

• jest-reporters: Apply global coverage threshold to unmatched pattern files in addition to glob/path thresholds

• [jest-reporters, jest-runner, jest-runtime, jest-transform] Fix coverage report not showing correct code coverage when using projects config option

• jest-runtime: Resolve expect and @jest/expect from the internal module registry so test-file imports share the same JestAssertionError as the global expect

• jest-runtime: Improve CJS-from-ESM interop: __esModule/Babel default unwrap, broader named-export coverage, and shared CJS singleton across importers

• jest-runtime: Load .js files with ESM syntax but no "type":"module" marker as native ESM

• jest-runtime: Extend the .js-with-ESM-syntax fallback to require() on Node v24.9+ - falls back to require(esm) when the CJS parser rejects ESM syntax

• jest-runtime: Fix deadlocks and double-evaluation in concurrent ESM and wasm imports

• jest-runtime: Fix error when require() is called after the Jest environment has been torn down

• jest-runtime: Fix missing error when import() is called after the Jest environment has been torn down

• jest-runtime: Fix virtual unstable_mockModule registrations not respected in ESM

• jest-runtime: Apply moduleNameMapper when resolving modules with require.resolve() and the paths option