jest-cli
Advanced tools
Package description
The jest-cli npm package is the command line interface for Jest, a popular JavaScript testing framework. It allows developers to run tests, configure Jest options, and interact with Jest directly from the command line. Jest is widely used for testing React applications, but it can also be used for testing other JavaScript code.
Running Tests
Run all tests in a project. This is the most basic and commonly used command to start the Jest test runner.
jestRunning Tests in Watch Mode
Run Jest in watch mode. This command will re-run tests when files change, which is useful during development.
jest --watchRunning Specific Tests
Run tests in a specific file or files matching a pattern. This allows for more targeted testing.
jest testFileNameConfiguring Jest
Specify a configuration file for Jest. This allows developers to customize how Jest behaves, including setting up test environments, mock implementations, and more.
jest --config=jest.config.jsCoverage Reporting
Generate a test coverage report. This helps developers understand which parts of their codebase are covered by tests.
jest --coverageMocha is a feature-rich JavaScript test framework running on Node.js and in the browser, making asynchronous testing simple. It's often compared to Jest but is considered more flexible and less opinionated, though it requires more setup and configuration.
Jasmine is a behavior-driven development framework for testing JavaScript code. It does not require a DOM and has no dependencies, making it suited for websites, Node.js projects, or anywhere JavaScript can run. It's similar to Jest but has a different syntax and set of features.
AVA is a test runner for Node.js with a concise API, detailed error output, and process isolation that lets you develop with confidence. It's different from Jest in that it runs tests concurrently, which can be faster, but it may not be as feature-rich as Jest.
Tape is a tap-producing test harness for Node.js and browsers. It's minimalistic and straightforward, with less abstraction than Jest. It's suitable for small to medium-sized projects that don't need the extensive features Jest provides.
Readme
Painless JavaScript Unit Testing
Familiar Approach: Built on top of Jasmine test framework, a familiar BDD testing environment
Mock by Default: Automatically mocks CommonJS modules returned by require(), making most existing code testable
Short Feedback Loop: Tests run in parallel and DOM apis are mocked so you can run tests on the command line
Check out the Getting Started tutorial for more in-depth details.
<generated_api_start />
jest objectjest.autoMockOff()jest.autoMockOn()jest.clearAllTimers()jest.dontMock(module)jest.genMockFromModule(moduleObj)jest.genMockFunction()jest.genMockFn()jest.mock(moduleName)jest.runAllTicks()jest.runAllTimers()jest.runOnlyPendingTimers()jest.setMock(moduleName, moduleExports)mockFn.mock.callsmockFn.mock.instancesmockFn.mockClear()mockFn.mockImplementation(fn)mockFn.mockImpl(fn)mockFn.mockReturnThis()mockFn.mockReturnValue(value)mockFn.mockReturnValueOnce(value)config.collectCoverage [boolean]config.collectCoverageOnlyFrom [object]config.modulePathIgnorePatterns [array]config.rootDir [string]config.scriptPreprocessor [string]config.setupEnvScriptFile [string]config.setupTestFrameworkScriptFile [string]config.testFileExtensions [array]config.testPathDirs [array]config.testPathIgnorePatterns [array]config.unmockedModulePathPatterns [array]jestrequire(module)require.requireActual(module)describe(name, fn)beforeEach(fn)afterEach(fn)it(name, fn)it.only(name, fn) executes only this test. Useful when investigating a failurepit(name, fn) helper for promisesexpect(value).not inverse the next comparison.toThrow(?message).toBe(value) comparison using ===.toEqual(value) deep comparison. Use jasmine.any(type) to be softer.toBeFalsy().toBeTruthy().toBeNull().toBeUndefined().toBeDefined().toMatch(regexp).toContain(string).toBeCloseTo(number, delta).toBeGreaterThan(number).toBeLessThan(number).toBeCalled().toBeCalledWith(arg, um, ents).lastCalledWith(arg, um, ents)<generated_api_end />
FAQs
Delightful JavaScript Testing.
The npm package jest-cli receives a total of 17,460,317 weekly downloads. As such, jest-cli popularity was classified as popular.
We found that jest-cli demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 3 open source maintainers collaborating on the project.
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