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npm · #932 most downloaded on npm
This module exports some utils for the `expect` function used in [Jest](https://jestjs.io/).
Last release 16 days ago
18 Sep 2026
Release timing varies
gaps range from 8 days to 5 months
Nearly every release is documented
notes for 43 of 43 stable releases
Nothing withdrawn
no release was ever pulled
5 years old
73 releases · first in 2022
One column per quarter.
[jest-worker] Add JestWorkerFarm helper type
[jest-serializer] Remove deprecated module from source tree
[jest-resolve] Expose ResolverOptions type (#12736)[expect] Add missing dependency jest-util (#12744)[jest-circus] Improve test.concurrent (#12748)[jest-resolve] Correctly throw an error if jsdom test environment is used, but not installed (#12749)[jest-serializer] Remove deprecated module from source tree (#12735)Full Changelog: https://github.com/facebook/jest/compare/v28.0.0...v28.0.1
[jest-config] [BREAKING] Do not normalize long deprecated configuration options preprocessorIgnorePatterns, scriptPreprocessor, setupTestFrameworkScri…
Blog post: https://jestjs.io/blog/2022/04/25/jest-28
[babel-jest] Export createTransformer function (#12399)[expect] Expose AsymmetricMatchers, MatcherFunction and MatcherFunctionWithState interfaces (#12363, #12376)[jest-circus] Support error logging before retry (#12201)[jest-circus, jest-jasmine2] Allowed classes and functions as describe and it/test names (#12484)[jest-cli, jest-config] [BREAKING] Remove testURL config, use testEnvironmentOptions.url instead (#10797)[jest-cli, jest-core] Add --shard parameter for distributed parallel test execution (#12546)[jest-cli] [BREAKING] Remove undocumented --timers option (#12572)[jest-config] [BREAKING] Stop shipping jest-environment-jsdom by default (#12354)[jest-config] [BREAKING] Stop shipping jest-jasmine2 by default (#12355)[jest-config, @jest/types] Add ci to GlobalConfig (#12378)[jest-config] [BREAKING] Rename moduleLoader to runtime (#10817)[jest-config] [BREAKING] Rename extraGlobals to sandboxInjectedGlobals (#10817)[jest-config] [BREAKING] Throw an error instead of showing a warning if multiple configs are used (#12510)[jest-config] [BREAKING] Do not normalize long deprecated configuration options preprocessorIgnorePatterns, scriptPreprocessor, setupTestFrameworkScriptFile and testPathDirs (#12701)[jest-cli, jest-core] Add --ignoreProjects CLI argument to ignore test suites by project name (#12620)[jest-core] Pass project config to globalSetup/globalTeardown function as second argument (#12440)[jest-core] Stabilize test runners with event emitters (#12641)[jest-core, jest-watcher] [BREAKING] Move TestWatcher class to jest-watcher package (#12652)[jest-core] Allow using Summary Reporter as stand-alone reporter (#12687)[jest-environment-jsdom] [BREAKING] Upgrade jsdom to 19.0.0 (#12290)[jest-environment-jsdom] [BREAKING] Add default browser condition to exportConditions for jsdom environment (#11924)[jest-environment-jsdom] [BREAKING] Pass global config to Jest environment constructor for jsdom environment (#12461)[jest-environment-jsdom] [BREAKING] Second argument context to constructor is mandatory (#12469)[jest-environment-node] [BREAKING] Add default node and node-addon conditions to exportConditions for node environment (#11924)[jest-environment-node] [BREAKING] Pass global config to Jest environment constructor for node environment (#12461)[jest-environment-node] [BREAKING] Second argument context to constructor is mandatory (#12469)[jest-environment-node] Add all available globals to test globals, not just explicit ones (#12642, #12696)[@jest/expect] New module which extends expect with jest-snapshot matchers (#12404, #12410, #12418)[@jest/expect-utils] New module exporting utils for expect (#12323)[@jest/fake-timers] [BREAKING] Rename timers configuration option to fakeTimers (#12572)[@jest/fake-timers] [BREAKING] Allow jest.useFakeTimers() and projectConfig.fakeTimers to take an options bag (#12572)[jest-haste-map] [BREAKING] HasteMap.create now returns a promise (#12008)[jest-haste-map] Add support for dependencyExtractor written in ESM (#12008)[jest-mock] [BREAKING] Rename exported utility types ClassLike, FunctionLike, ConstructorLikeKeys, MethodLikeKeys, PropertyLikeKeys; remove exports of utility types ArgumentsOf, ArgsType, ConstructorArgumentsOf - TS builtin utility types ConstructorParameters and Parameters should be used instead (#12435, #12489)[jest-mock] Improve isMockFunction to infer types of passed function (#12442)[jest-mock] [BREAKING] Improve the usage of jest.fn generic type argument (#12489)[jest-mock] Add support for auto-mocking async generator functions (#11080)[jest-mock] Add contexts member to mock functions (#12601)[@jest/reporters] Add GitHub Actions reporter (#11320, #12658)[@jest/reporters] Pass reporterContext to custom reporter constructors as third argument (#12657)[jest-resolve] [BREAKING] Add support for package.json exports (#11961, #12373)[jest-resolve] Support package self-reference (#12682)[jest-resolve, jest-runtime] Add support for data: URI import and mock (#12392)[jest-resolve, jest-runtime] Add support for async resolver (#11540)[jest-resolve] [BREAKING] Remove browser?: boolean from resolver options, conditions: ['browser'] should be used instead (#12707)[jest-resolve] Expose JestResolver, AsyncResolver, SyncResolver, PackageFilter, PathFilter and PackageJSON types (#12707, (#12712)[jest-runner] Allow setupFiles module to export an async function (#12042)[jest-runner] Allow passing testEnvironmentOptions via docblocks (#12470)[jest-runner] Expose CallbackTestRunner, EmittingTestRunner abstract classes and CallbackTestRunnerInterface, EmittingTestRunnerInterface to help typing third party runners (#12646, #12715)[jest-runner] Lock version of source-map-support to 0.5.13 (#12720)[jest-runtime] [BREAKING] Runtime.createHasteMap now returns a promise (#12008)[jest-runtime] Calling jest.resetModules function will clear FS and transform cache (#12531)[jest-runtime] [BREAKING] Remove Context type export, it must be imported from @jest/test-result (#12685)[jest-runtime] Add import.meta.jest (#12698)[@jest/schemas] New module for JSON schemas for Jest's config (#12384)[@jest/source-map] Migrate from source-map to @jridgewell/trace-mapping (#12692)[jest-transform] [BREAKING] Make it required for process() and processAsync() methods to always return structured data (#12638)[jest-test-result] Add duration property to JSON test output (#12518)[jest-watcher] [BREAKING] Make PatternPrompt class to take entityName as third constructor parameter instead of this._entityName (#12591)[jest-worker] [BREAKING] Allow only absolute workerPath (#12343)[jest-worker] [BREAKING] Default to advanced serialization when using child process workers (#10983)[pretty-format] New maxWidth parameter (#12402)[*] Use sha256 instead of md5 as hashing algortihm for compatibility with FIPS systems (#12722)[babel-jest] [BREAKING] Pass rootDir as root in Babel's options (#12689)[expect] Move typings of .not, .rejects and .resolves modifiers outside of Matchers interface (#12346)[expect] Throw useful error if expect.extend is called with invalid matchers (#12488)[expect] Fix iterableEquality ignores other properties (#8359)[expect] Fix print for the closeTo matcher (#12626)[jest-changed-files] Improve changedFilesWithAncestor pattern for Mercurial SCM (#12322)[jest-circus, @jest/types] Disallow undefined value in TestContext type (#12507)[jest-config] Correctly detect CI environment and update snapshots accordingly (#12378)[jest-config] Pass moduleTypes to ts-node to enforce CJS when transpiling (#12397)[jest-config] [BREAKING] Add mjs and cjs to default moduleFileExtensions config (#12578)[jest-config, jest-haste-map] Allow searching for tests in node_modules by exposing retainAllFiles (#11084)[jest-core] [BREAKING] Exit with status 1 if no tests are found with --findRelatedTests flag (#12487)[jest-core] Do not report unref-ed subprocesses as open handles (#12705)[jest-each] %# is not replaced with index of the test case (#12517)[jest-each] Fixes error message with incorrect count of missing arguments (#12464)[jest-environment-jsdom] Make jsdom accessible to extending environments again (#12232)[jest-environment-jsdom] Log JSDOM errors more cleanly (#12386)[jest-environment-node] Add MessageChannel, MessageEvent to globals (#12553)[jest-environment-node] Add structuredClone to globals (#12631)[@jest/expect-utils] [BREAKING] Fix false positives when looking for undefined prop (#8923)[jest-haste-map] Don't use partial results if file crawl errors (#12420)[jest-haste-map] Make watchman existence check lazy+async (#12675)[jest-jasmine2, jest-types] [BREAKING] Move all jasmine specific types from @jest/types to its own package (#12125)[jest-jasmine2] Do not set duration to 0 for skipped tests (#12518)[jest-matcher-utils] Pass maxWidth to pretty-format to avoid printing every element in arrays by default (#12402)[jest-mock] Fix function overloads for spyOn to allow more correct type inference in complex object (#12442)[jest-mock] Handle overridden Function.name property (#12674)[@jest/reporters] Notifications generated by the --notify flag are no longer persistent in GNOME Shell. (#11733)[@jest/reporters] Move missing icon file which is needed for NotifyReporter class. (#12593)[@jest/reporters] Update v8-to-istanbul (#12697)[jest-resolver] Call custom resolver with core node.js modules (#12654)[jest-runner] Correctly resolve source-map-support (#12706)[jest-worker] Fix Farm execution results memory leak (#12497)[*] [BREAKING] Drop support for Node v10 and v15 and target first LTS 16.13.0 (#12220)[*] [BREAKING] Drop support for typescript@3.8, minimum version is now 4.3 (#11142, #12648)[*] Bundle all .d.ts files into a single index.d.ts per module (#12345)[*] Use globalThis instead of global (#12447)[babel-jest] [BREAKING] Only export createTransformer (#12407)[docs] Add note about not mixing done() with Promises (#11077)[docs, examples] Update React examples to match with the new React guidelines for code examples (#12217)[docs] Add clarity for module factory hoisting limitations (#12453)[docs] Add more information about how code transformers work (#12407)[docs] Add upgrading guide (#12633)[expect] [BREAKING] Remove support for importing build/utils (#12323)[expect] [BREAKING] Migrate to ESM (#12344)[expect] [BREAKING] Snapshot matcher types are moved to @jest/expect (#12404)[jest-cli] Update yargs to v17 (#12357)[jest-config] [BREAKING] Remove getTestEnvironment export (#12353)[jest-config] [BREAKING] Rename config option name to id (#11981)[jest-create-cache-key-function] Added README.md file with basic usage instructions (#12492)[@jest/core] Use index.ts instead of jest.ts as main export (#12329)[jest-environment-jsdom] [BREAKING] Migrate to ESM (#12340)[jest-environment-node] [BREAKING] Migrate to ESM (#12340)[jest-haste-map] Remove legacy isRegExpSupported (#12676)[@jest/fake-timers] Update @sinonjs/fake_timers to v9 (#12357)[jest-jasmine2, jest-runtime] [BREAKING] Use Symbol to pass jest.setTimeout value instead of jasmine specific logic (#12124)[jest-phabricator] [BREAKING] Migrate to ESM (#12341)[jest-resolve] [BREAKING] Make requireResolveFunction argument mandatory (#12353)[jest-runner] [BREAKING] Remove some type exports from @jest/test-result (#12353)[jest-runner] [BREAKING] Second argument to constructor (Context) is not optional (#12640)[jest-serializer] [BREAKING] Deprecate package in favour of using v8 APIs directly (#12391)[jest-snapshot] [BREAKING] Migrate to ESM (#12342)[jest-transform] Update write-file-atomic to v4 (#12357)[jest-types] [BREAKING] Remove Config.Glob and Config.Path (#12406)[jest] Use index.ts instead of jest.ts as main export (#12329)[jest-haste-map] [BREAKING] Default to node crawler over shelling out to find if watchman is not enabled (#12320)Full Changelog: https://github.com/facebook/jest/compare/v27.5.1...v28.0.0
[jest-core] Stabilize test runners with event emitters
[jest-core] Stabilize test runners with event emitters (#12641)[jest-core, jest-watcher] [BREAKING] Move TestWatcher class to jest-watcher package (#12652)[jest-core] Allow using Summary Reporter as stand-alone reporter (#12687)[jest-environment-node] Add all available globals to test globals, not just explicit ones (#12642)[@jest/reporters] Add GitHub Actions reporter (#12658)[@jest/reporters] Pass reporterContext to custom reporter constructors as third argument (#12657)[jest-resolve] Support package self-reference (#12682)[jest-runner] Exposing CallbackTestRunner, EmittingTestRunner abstract classes to help typing third party runners (#12646)[jest-runtime] [BREAKING] Remove Context type export, it must be imported from @jest/test-result (#12685)[jest-transform] [BREAKING] Make it required for process() and processAsync() methods to always return structured data (#12638)[expect] Fix print for the closeTo matcher (#12626)[jest-each] Fixes error message with incorrect count of missing arguments (#12464)[jest-haste-map] Make watchman existence check lazy+async (#12675)[jest-mock] Handle overridden Function.name property (#12674)[jest-resolver] Call custom resolver with core node.js modules (#12654)[*] [BREAKING] Drop support for typescript@4.2, minimum version is now 4.3 (#12648)[docs] Add upgrading guide (#12633)[jest-config] [BREAKING] Rename config option name to id (#11981)[jest-haste-map] Remove legacy isRegExpSupported (#12676)[jest-runner] [BREAKING] Second argument to constructor (Context) is not optional (#12640)Full Changelog: https://github.com/facebook/jest/compare/v28.0.0-alpha.8...v28.0.0-alpha.9
[jest-cli] [BREAKING] Remove undocumented --timers option
[jest-cli] [BREAKING] Remove undocumented --timers option (#12572)[jest-cli, jest-core] Add --ignoreProjects CLI argument to ignore test suites by project name (#12620)[@jest/fake-timers] [BREAKING] Rename timers configuration option to fakeTimers (#12572)[@jest/fake-timers] [BREAKING] Allow jest.useFakeTimers() and projectConfig.fakeTimers to take an options bag (#12572)[jest-mock] Add contexts member to mock functions (#12601)[jest-reporters] Add GitHub Actions reporter (#11320)[jest-watcher] [BREAKING] Make PatternPrompt class to take entityName as third constructor parameter instead of this._entityName (#12591)[jest-config] [BREAKING] Add mjs and cjs to default moduleFileExtensions config (#12578)[jest-environment-node] Add MessageChannel, MessageEvent to globals (#12553)[jest-environment-node] Add structuredClone to globals (#12631)[@jest/reporters] Move missing icon file which is needed for NotifyReporter class. (#12593)[babel-jest] [BREAKING] Only export createTransformer (#12407)[docs] Add more information about how code transformers work (#12407)Full Changelog: https://github.com/facebook/jest/compare/v28.0.0-alpha.7...v28.0.0-alpha.8
[jest-cli, jest-core] Add --shard parameter for distributed parallel test execution
[jest-cli, jest-core] Add --shard parameter for distributed parallel test execution (#12546)[jest-runtime] Calling jest.resetModules function will clear FS and transform cache (#12531)[jest-test-result] Add duration property to JSON test output (#12518)[jest-jasmine2] Do not set duration to 0 for skipped tests (#12518)Full Changelog: https://github.com/facebook/jest/compare/v28.0.0-alpha.6...v28.0.0-alpha.7
[jest-config] [BREAKING] Throw an error instead of showing a warning if multiple configs are used
[jest-config] [BREAKING] Throw an error instead of showing a warning if multiple configs are used (#12510)[jest-mock] [BREAKING] Rename exported utility types ClassLike, FunctionLike, ConstructorLikeKeys, MethodLikeKeys, PropertyLikeKeys; remove exports of utility types ArgumentsOf, ArgsType, ConstructorArgumentsOf - TS builtin utility types ConstructorParameters and Parameters should be used instead (#12435, #12489)[jest-mock] [BREAKING] Improve the usage of jest.fn generic type argument (#12489)[jest-runner] Allow setupFiles module to export an async function (#12042)[jest-circus, @jest/types] Disallow undefined value in TestContext type (#12507)[jest-each] %# is not replaced with index of the test case (#12517)[jest-reporters] Notifications generated by the --notify flag are no longer persistent in GNOME Shell. (#11733)[jest-worker] Fix Farm execution results memory leak (#12497)[jest-create-cache-key-function] Added README.md file with basic usage instructions (#12492)Full Changelog: https://github.com/facebook/jest/compare/v28.0.0-alpha.5...v28.0.0-alpha.6
[jest-circus, jest-jasmine2] Allowed classes and functions as describe and it/test names
[jest-circus, jest-jasmine2] Allowed classes and functions as describe and it/test names (#12484)[jest-cli, jest-config] [BREAKING] Remove testURL config, use testEnvironmentOptions.url instead (#10797)[jest-config] [BREAKING] Rename moduleLoader to runtime (#10817)[jest-config] [BREAKING] Rename extraGlobals to sandboxInjectedGlobals (#10817)[jest-environment-jsdom] [BREAKING] Pass global config to Jest environment constructor for jsdom environment (#12461)[jest-environment-jsdom] [BREAKING] Second argument context to constructor is mandatory (#12469)[jest-environment-node] [BREAKING] Pass global config to Jest environment constructor for node environment (#12461)[jest-environment-node] [BREAKING] Second argument context to constructor is mandatory (#12469)[jest-haste-map] [BREAKING] HasteMap.create now returns a promise (#12008)[jest-haste-map] Add support for dependencyExtractor written in ESM (#12008)[jest-mock] [BREAKING] Rename exported utility types ConstructorLike, MethodLike, ConstructorLikeKeys, MethodLikeKeys, PropertyLikeKeys; remove exports of utility types ArgumentsOf, ArgsType, ConstructorArgumentsOf - TS builtin utility types ConstructorParameters and Parameters should be used instead (#12435)[jest-mock] Add support for auto-mocking async generator functions (#11080)[jest-runner] Allow passing testEnvironmentOptions via docblocks (#12470)[jest-runtime] [BREAKING] Runtime.createHasteMap now returns a promise (#12008)[expect] Throw useful error if expect.extend is called with invalid matchers (#12488)[expect] Fix iterableEquality ignores other properties (#8359)[jest-config, jest-haste-map] Allow searching for tests in node_modules by exposing retainAllFiles (#11084)[jest-core] [BREAKING] Exit with status 1 if no tests are found with --findRelatedTests flag (#12487)[jest-environment-jsdom] Log JSDOM errors more cleanly (#12386)[@jest/expect-utils] [BREAKING] Fix false positives when looking for undefined prop (#8923)Full Changelog: https://github.com/facebook/jest/compare/v28.0.0-alpha.4...v28.0.0-alpha.5
[jest-core] Pass project config to globalSetup/globalTeardown function as second argument
[jest-core] Pass project config to globalSetup/globalTeardown function as second argument (#12440)[jest-mock] Improve isMockFunction to infer types of passed function (#12442)[jest-resolve, jest-runtime] Add support for async resolver (#11540)[jest-haste-map] Don't use partial results if file crawl errors (#12420)[jest-mock] Fix function overloads for spyOn to allow more correct type inference in complex object (#12442)[*] Use globalThis instead of global (#12447)Full Changelog: https://github.com/facebook/jest/compare/v28.0.0-alpha.3...v28.0.0-alpha.4
[jest-resolve] Support directory remapping in package.json exports
[jest-resolve] Support directory remapping in package.json exports (#12373)Full Changelog: https://github.com/facebook/jest/compare/v28.0.0-alpha.2..v28.0.0-alpha.3
[@jest/expect] New module which extends expect with jest-snapshot matchers (#12404, #12410)
[@jest/expect] New module which extends expect with jest-snapshot matchers (#12404, #12410)[jest-resolve, jest-runtime] Add support for data: URI import and mock (#12392)[pretty-format] New maxWidth parameter (#12402)[jest-matcher-utils] Pass maxWidth to pretty-format to avoid printing every element in arrays by default (#12402)[expect] [BREAKING] Snapshot matcher types are moved to @jest/expect (#12404)Full Changelog: https://github.com/facebook/jest/compare/v28.0.0-alpha.1...v28.0.0-alpha.2
[jest-serializer] [BREAKING] Deprecate package in favour of using v8 APIs directly
[babel-jest] Export createTransformer function (#12399)[expect] Expose AsymmetricMatchers, MatcherFunction and MatcherFunctionWithState interfaces (#12363, #12376)[jest-config, @jest/types] Add ci to GlobalConfig (#12378)[@jest/schemas] New module for JSON schemas for Jest's config (#12384)[jest-config] Correctly detect CI environment and update snapshots accordingly (#12378)[jest-config] Pass moduleTypes to ts-node to enforce CJS when transpiling (#12397)[docs, examples] Update React examples to match with the new React guidelines for code examples (#12217)[docs] Add note about not mixing done() with Promises (#11077)[jest-serializer] [BREAKING] Deprecate package in favour of using v8 APIs directly (#12391)Full Changelog: https://github.com/facebook/jest/compare/v28.0.0-alpha.0...v28.0.0-alpha.1
[jest-config] [BREAKING] Stop shipping jest-environment-jsdom by default
[jest-config] [BREAKING] Stop shipping jest-environment-jsdom by default (#12354)[jest-config] [BREAKING] Stop shipping jest-jasmine2 by default (#12355)[jest-environment-jsdom] [BREAKING] Upgrade jsdom to 19.0.0 (#12290)[jest-environment-jsdom] [BREAKING] Add default browser condition to exportConditions for jsdom environment (#11924)[jest-environment-node] [BREAKING] Add default node and node-addon conditions to exportConditions for node environment (#11924)[@jest/expect-utils] New module exporting utils for expect (#12323)[jest-resolve] [BREAKING] Add support for package.json exports (#11961)[jest-worker] [BREAKING] Allow only absolute workerPath (#12343)[expect] Move typings of .not, .rejects and .resolves modifiers outside of Matchers interface (#12346)[jest-environment-jsdom] Make jsdom accessible to extending environments again (#12232)[jest-jasmine2, jest-types] [BREAKING] Move all jasmine specific types from @jest/types to its own package (#12125)[*] [BREAKING] Drop support for Node v10 and v15 and target first LTS 16.13.0 (#12220)[*] [BREAKING] Drop support for typescript@3.8, minimum version is now 4.2 (#11142)[*] Bundle all .d.ts files into a single index.d.ts per module (#12345)[expect] [BREAKING] Remove support for importing build/utils (#12323)[expect] [BREAKING] Migrate to ESM (#12344)[jest-cli] Update yargs to v17 (#12357)[jest-config] [BREAKING] Remove getTestEnvironment export (#12353)[@jest/core] Use index.ts instead of jest.ts as main export (#12329)[jest-environment-jsdom] [BREAKING] Migrate to ESM (#12340)[jest-environment-node] [BREAKING] Migrate to ESM (#12340)[@jest/fake-timers] Update @sinonjs/fake_timers to v9 (#12357)[jest-jasmine2, jest-runtime] [BREAKING] Use Symbol to pass jest.setTimeout value instead of jasmine specific logic (#12124)[jest-phabricator] [BREAKING] Migrate to ESM (#12341)[jest-resolve] [BREAKING] Make requireResolveFunction argument mandatory (#12353)[jest-runner] [BREAKING] Remove some type exports from @jest/test-result (#12353)[jest-snapshot] [BREAKING] Migrate to ESM (#12342)[jest-transform] Update write-file-atomic to v4 (#12357)[jest] Use index.ts instead of jest.ts as main export (#12329)[jest-haste-map] [BREAKING] Default to node crawler over shelling out to find if watchman is not enabled (#12320)Full Changelog: https://github.com/facebook/jest/compare/v27.5.1...v28.0.0-alpha.0
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