/** * The `node:test` module provides a standalone testing module. * @see [source](https://github.com/nodejs/node/blob/v18.x/lib/test.js) */ declare module 'node:test' { /** * Programmatically start the test runner. * @since v18.9.0 * @param options Configuration options for running tests. * @returns A {@link TapStream} that emits events about the test execution. */ function run(options?: RunOptions): TapStream; /** * The `test()` function is the value imported from the test module. Each invocation of this * function results in the creation of a test point in the TAP output. * * The {@link TestContext} object passed to the fn argument can be used to perform actions * related to the current test. Examples include skipping the test, adding additional TAP * diagnostic information, or creating subtests. * * `test()` returns a {@link Promise} that resolves once the test completes. The return value * can usually be discarded for top level tests. However, the return value from subtests should * be used to prevent the parent test from finishing first and cancelling the subtest as shown * in the following example. * * ```js * test('top level test', async (t) => { * // The setTimeout() in the following subtest would cause it to outlive its * // parent test if 'await' is removed on the next line. Once the parent test * // completes, it will cancel any outstanding subtests. * await t.test('longer running subtest', async (t) => { * return new Promise((resolve, reject) => { * setTimeout(resolve, 1000); * }); * }); * }); * ``` * @since v18.0.0 * @param name The name of the test, which is displayed when reporting test results. * Default: The `name` property of fn, or `''` if `fn` does not have a name. * @param options Configuration options for the test * @param fn The function under test. The first argument to this function is a * {@link TestContext} object. If the test uses callbacks, the callback function is * passed as the second argument. Default: A no-op function. * @returns A {@link Promise} resolved with `undefined` once the test completes. */ function test(name?: string, fn?: TestFn): Promise; function test(name?: string, options?: TestOptions, fn?: TestFn): Promise; function test(options?: TestOptions, fn?: TestFn): Promise; function test(fn?: TestFn): Promise; /** * @since v18.6.0 * @param name The name of the suite, which is displayed when reporting suite results. * Default: The `name` property of fn, or `''` if `fn` does not have a name. * @param options Configuration options for the suite * @param fn The function under suite. Default: A no-op function. */ function describe(name?: string, options?: TestOptions, fn?: SuiteFn): void; function describe(name?: string, fn?: SuiteFn): void; function describe(options?: TestOptions, fn?: SuiteFn): void; function describe(fn?: SuiteFn): void; namespace describe { // Shorthand for skipping a suite, same as `describe([name], { skip: true }[, fn])`. function skip(name?: string, options?: TestOptions, fn?: SuiteFn): void; function skip(name?: string, fn?: SuiteFn): void; function skip(options?: TestOptions, fn?: SuiteFn): void; function skip(fn?: SuiteFn): void; // Shorthand for marking a suite as `TODO`, same as `describe([name], { todo: true }[, fn])`. function todo(name?: string, options?: TestOptions, fn?: SuiteFn): void; function todo(name?: string, fn?: SuiteFn): void; function todo(options?: TestOptions, fn?: SuiteFn): void; function todo(fn?: SuiteFn): void; } /** * @since v18.6.0 * @param name The name of the test, which is displayed when reporting test results. * Default: The `name` property of fn, or `''` if `fn` does not have a name. * @param options Configuration options for the test * @param fn The function under test. If the test uses callbacks, the callback function is * passed as the second argument. Default: A no-op function. */ function it(name?: string, options?: TestOptions, fn?: ItFn): void; function it(name?: string, fn?: ItFn): void; function it(options?: TestOptions, fn?: ItFn): void; function it(fn?: ItFn): void; namespace it { // Shorthand for skipping a test, same as `it([name], { skip: true }[, fn])`. function skip(name?: string, options?: TestOptions, fn?: ItFn): void; function skip(name?: string, fn?: ItFn): void; function skip(options?: TestOptions, fn?: ItFn): void; function skip(fn?: ItFn): void; // Shorthand for marking a test as `TODO`, same as `it([name], { todo: true }[, fn])`. function todo(name?: string, options?: TestOptions, fn?: ItFn): void; function todo(name?: string, fn?: ItFn): void; function todo(options?: TestOptions, fn?: ItFn): void; function todo(fn?: ItFn): void; } /** * The type of a function under test. The first argument to this function is a * {@link TestContext} object. If the test uses callbacks, the callback function is passed as * the second argument. */ type TestFn = (t: TestContext, done: (result?: any) => void) => any; /** * The type of a function under Suite. * If the test uses callbacks, the callback function is passed as an argument */ type SuiteFn = (done: (result?: any) => void) => void; /** * The type of a function under test. * If the test uses callbacks, the callback function is passed as an argument */ type ItFn = (done: (result?: any) => void) => any; interface RunOptions { /** * If a number is provided, then that many files would run in parallel. * If truthy, it would run (number of cpu cores - 1) files in parallel. * If falsy, it would only run one file at a time. * If unspecified, subtests inherit this value from their parent. * @default true */ concurrency?: number | boolean | undefined; /** * An array containing the list of files to run. * If unspecified, the test runner execution model will be used. */ files?: readonly string[] | undefined; /** * Allows aborting an in-progress test execution. * @default undefined */ signal?: AbortSignal | undefined; /** * A number of milliseconds the test will fail after. * If unspecified, subtests inherit this value from their parent. * @default Infinity */ timeout?: number | undefined; /** * Sets inspector port of test child process. * If a nullish value is provided, each process gets its own port, * incremented from the primary's `process.debugPort`. */ inspectPort?: number | (() => number) | undefined; } /** * A successful call of the `run()` method will return a new `TapStream` object, * streaming a [TAP](https://testanything.org/) output. * `TapStream` will emit events in the order of the tests' definitions. * @since v18.9.0 */ interface TapStream extends NodeJS.ReadableStream { addListener(event: 'test:diagnostic', listener: (message: string) => void): this; addListener(event: 'test:fail', listener: (data: TestFail) => void): this; addListener(event: 'test:pass', listener: (data: TestPass) => void): this; addListener(event: string, listener: (...args: any[]) => void): this; emit(event: 'test:diagnostic', message: string): boolean; emit(event: 'test:fail', data: TestFail): boolean; emit(event: 'test:pass', data: TestPass): boolean; emit(event: string | symbol, ...args: any[]): boolean; on(event: 'test:diagnostic', listener: (message: string) => void): this; on(event: 'test:fail', listener: (data: TestFail) => void): this; on(event: 'test:pass', listener: (data: TestPass) => void): this; on(event: string, listener: (...args: any[]) => void): this; once(event: 'test:diagnostic', listener: (message: string) => void): this; once(event: 'test:fail', listener: (data: TestFail) => void): this; once(event: 'test:pass', listener: (data: TestPass) => void): this; once(event: string, listener: (...args: any[]) => void): this; prependListener(event: 'test:diagnostic', listener: (message: string) => void): this; prependListener(event: 'test:fail', listener: (data: TestFail) => void): this; prependListener(event: 'test:pass', listener: (data: TestPass) => void): this; prependListener(event: string, listener: (...args: any[]) => void): this; prependOnceListener(event: 'test:diagnostic', listener: (message: string) => void): this; prependOnceListener(event: 'test:fail', listener: (data: TestFail) => void): this; prependOnceListener(event: 'test:pass', listener: (data: TestPass) => void): this; prependOnceListener(event: string, listener: (...args: any[]) => void): this; } interface TestFail { /** * The test duration. */ duration: number; /** * The failure casing test to fail. */ error: Error; /** * The test name. */ name: string; /** * The ordinal number of the test. */ testNumber: number; /** * Present if `context.todo` is called. */ todo?: string; /** * Present if `context.skip` is called. */ skip?: string; } interface TestPass { /** * The test duration. */ duration: number; /** * The test name. */ name: string; /** * The ordinal number of the test. */ testNumber: number; /** * Present if `context.todo` is called. */ todo?: string; /** * Present if `context.skip` is called. */ skip?: string; } /** * An instance of `TestContext` is passed to each test function in order to interact with the * test runner. However, the `TestContext` constructor is not exposed as part of the API. * @since v18.0.0 */ interface TestContext { /** * This function is used to create a hook running before each subtest of the current test. * @param fn The hook function. If the hook uses callbacks, the callback function is passed as * the second argument. Default: A no-op function. * @param options Configuration options for the hook. * @since v18.8.0 */ beforeEach: typeof beforeEach; /** * This function is used to create a hook that runs after the current test finishes. * @param fn The hook function. If the hook uses callbacks, the callback function is passed as * the second argument. Default: A no-op function. * @param options Configuration options for the hook. * @since v18.13.0 */ after: typeof after; /** * This function is used to create a hook running after each subtest of the current test. * @param fn The hook function. If the hook uses callbacks, the callback function is passed as * the second argument. Default: A no-op function. * @param options Configuration options for the hook. * @since v18.8.0 */ afterEach: typeof afterEach; /** * This function is used to write TAP diagnostics to the output. Any diagnostic information is * included at the end of the test's results. This function does not return a value. * @param message Message to be displayed as a TAP diagnostic. * @since v18.0.0 */ diagnostic(message: string): void; /** * The name of the test. * @since v18.8.0 */ readonly name: string; /** * If `shouldRunOnlyTests` is truthy, the test context will only run tests that have the `only` * option set. Otherwise, all tests are run. If Node.js was not started with the `--test-only` * command-line option, this function is a no-op. * @param shouldRunOnlyTests Whether or not to run `only` tests. * @since v18.0.0 */ runOnly(shouldRunOnlyTests: boolean): void; /** * Can be used to abort test subtasks when the test has been aborted. * @since v18.7.0 */ readonly signal: AbortSignal; /** * This function causes the test's output to indicate the test as skipped. If `message` is * provided, it is included in the TAP output. Calling `skip()` does not terminate execution of * the test function. This function does not return a value. * @param message Optional skip message to be displayed in TAP output. * @since v18.0.0 */ skip(message?: string): void; /** * This function adds a `TODO` directive to the test's output. If `message` is provided, it is * included in the TAP output. Calling `todo()` does not terminate execution of the test * function. This function does not return a value. * @param message Optional `TODO` message to be displayed in TAP output. * @since v18.0.0 */ todo(message?: string): void; /** * This function is used to create subtests under the current test. This function behaves in * the same fashion as the top level {@link test} function. * @since v18.0.0 * @param name The name of the test, which is displayed when reporting test results. * Default: The `name` property of fn, or `''` if `fn` does not have a name. * @param options Configuration options for the test * @param fn The function under test. This first argument to this function is a * {@link TestContext} object. If the test uses callbacks, the callback function is * passed as the second argument. Default: A no-op function. * @returns A {@link Promise} resolved with `undefined` once the test completes. */ test: typeof test; /** * Each test provides its own MockTracker instance. */ readonly mock: MockTracker; } interface TestOptions { /** * If a number is provided, then that many tests would run in parallel. * If truthy, it would run (number of cpu cores - 1) tests in parallel. * For subtests, it will be `Infinity` tests in parallel. * If falsy, it would only run one test at a time. * If unspecified, subtests inherit this value from their parent. * @default false */ concurrency?: number | boolean | undefined; /** * If truthy, and the test context is configured to run `only` tests, then this test will be * run. Otherwise, the test is skipped. * @default false */ only?: boolean | undefined; /** * Allows aborting an in-progress test. * @since v18.8.0 */ signal?: AbortSignal | undefined; /** * If truthy, the test is skipped. If a string is provided, that string is displayed in the * test results as the reason for skipping the test. * @default false */ skip?: boolean | string | undefined; /** * A number of milliseconds the test will fail after. If unspecified, subtests inherit this * value from their parent. * @default Infinity * @since v18.7.0 */ timeout?: number | undefined; /** * If truthy, the test marked as `TODO`. If a string is provided, that string is displayed in * the test results as the reason why the test is `TODO`. * @default false */ todo?: boolean | string | undefined; } /** * This function is used to create a hook running before running a suite. * @param fn The hook function. If the hook uses callbacks, the callback function is passed as * the second argument. Default: A no-op function. * @param options Configuration options for the hook. * @since v18.8.0 */ function before(fn?: HookFn, options?: HookOptions): void; /** * This function is used to create a hook running after running a suite. * @param fn The hook function. If the hook uses callbacks, the callback function is passed as * the second argument. Default: A no-op function. * @param options Configuration options for the hook. * @since v18.8.0 */ function after(fn?: HookFn, options?: HookOptions): void; /** * This function is used to create a hook running before each subtest of the current suite. * @param fn The hook function. If the hook uses callbacks, the callback function is passed as * the second argument. Default: A no-op function. * @param options Configuration options for the hook. * @since v18.8.0 */ function beforeEach(fn?: HookFn, options?: HookOptions): void; /** * This function is used to create a hook running after each subtest of the current test. * @param fn The hook function. If the hook uses callbacks, the callback function is passed as * the second argument. Default: A no-op function. * @param options Configuration options for the hook. * @since v18.8.0 */ function afterEach(fn?: HookFn, options?: HookOptions): void; /** * The hook function. If the hook uses callbacks, the callback function is passed as the * second argument. */ type HookFn = (done: (result?: any) => void) => any; /** * Configuration options for hooks. * @since v18.8.0 */ interface HookOptions { /** * Allows aborting an in-progress hook. */ signal?: AbortSignal | undefined; /** * A number of milliseconds the hook will fail after. If unspecified, subtests inherit this * value from their parent. * @default Infinity */ timeout?: number | undefined; } interface MockFunctionOptions { /** * The number of times that the mock will use the behavior of `implementation`. * Once the mock function has been called `times` times, * it will automatically restore the behavior of `original`. * This value must be an integer greater than zero. * @default Infinity */ times?: number | undefined; } interface MockMethodOptions extends MockFunctionOptions { /** * If `true`, `object[methodName]` is treated as a getter. * This option cannot be used with the `setter` option. */ getter?: boolean | undefined; /** * If `true`, `object[methodName]` is treated as a setter. * This option cannot be used with the `getter` option. */ setter?: boolean | undefined; } type Mock = F & { mock: MockFunctionContext; }; type NoOpFunction = (...args: any[]) => undefined; type FunctionPropertyNames = { [K in keyof T]: T[K] extends Function ? K : never; }[keyof T]; interface MockTracker { /** * This function is used to create a mock function. * @param original An optional function to create a mock on. * @param implementation An optional function used as the mock implementation for `original`. * This is useful for creating mocks that exhibit one behavior for a specified number of calls and then restore the behavior of `original`. * @param options Optional configuration options for the mock function. */ fn(original?: F, options?: MockFunctionOptions): Mock; fn(original?: F, implementation?: Implementation, options?: MockFunctionOptions): Mock; /** * This function is used to create a mock on an existing object method. * @param object The object whose method is being mocked. * @param methodName The identifier of the method on `object` to mock. If `object[methodName]` is not a function, an error is thrown. * @param implementation An optional function used as the mock implementation for `object[methodName]`. * @param options Optional configuration options for the mock method. */ method< MockedObject extends object, MethodName extends FunctionPropertyNames, >( object: MockedObject, methodName: MethodName, options?: MockFunctionOptions, ): MockedObject[MethodName] extends Function ? Mock : never; method< MockedObject extends object, MethodName extends FunctionPropertyNames, Implementation extends Function, >( object: MockedObject, methodName: MethodName, implementation: Implementation, options?: MockFunctionOptions, ): MockedObject[MethodName] extends Function ? Mock : never; method( object: MockedObject, methodName: keyof MockedObject, options: MockMethodOptions, ): Mock; method( object: MockedObject, methodName: keyof MockedObject, implementation: Function, options: MockMethodOptions, ): Mock; /** * This function is syntax sugar for {@link MockTracker.method} with `options.getter` set to `true`. */ getter< MockedObject extends object, MethodName extends keyof MockedObject, >( object: MockedObject, methodName: MethodName, options?: MockFunctionOptions, ): Mock<() => MockedObject[MethodName]>; getter< MockedObject extends object, MethodName extends keyof MockedObject, Implementation extends Function, >( object: MockedObject, methodName: MethodName, implementation?: Implementation, options?: MockFunctionOptions, ): Mock<(() => MockedObject[MethodName]) | Implementation>; /** * This function is syntax sugar for {@link MockTracker.method} with `options.setter` set to `true`. */ setter< MockedObject extends object, MethodName extends keyof MockedObject, >( object: MockedObject, methodName: MethodName, options?: MockFunctionOptions, ): Mock<(value: MockedObject[MethodName]) => void>; setter< MockedObject extends object, MethodName extends keyof MockedObject, Implementation extends Function, >( object: MockedObject, methodName: MethodName, implementation?: Implementation, options?: MockFunctionOptions, ): Mock<((value: MockedObject[MethodName]) => void) | Implementation>; /** * This function restores the default behavior of all mocks that were previously created by this `MockTracker` * and disassociates the mocks from the `MockTracker` instance. Once disassociated, the mocks can still be used, * but the `MockTracker` instance can no longer be used to reset their behavior or otherwise interact with them. * * After each test completes, this function is called on the test context's `MockTracker`. * If the global `MockTracker` is used extensively, calling this function manually is recommended. */ reset(): void; /** * This function restores the default behavior of all mocks that were previously created by this `MockTracker`. * Unlike `mock.reset()`, `mock.restoreAll()` does not disassociate the mocks from the `MockTracker` instance. */ restoreAll(): void; } const mock: MockTracker; interface MockFunctionCall< F extends Function, ReturnType = F extends (...args: any) => infer T ? T : F extends abstract new (...args: any) => infer T ? T : unknown, Args = F extends (...args: infer Y) => any ? Y : F extends abstract new (...args: infer Y) => any ? Y : unknown[], > { /** * An array of the arguments passed to the mock function. */ arguments: Args; /** * If the mocked function threw then this property contains the thrown value. */ error: unknown | undefined; /** * The value returned by the mocked function. * * If the mocked function threw, it will be `undefined`. */ result: ReturnType | undefined; /** * An `Error` object whose stack can be used to determine the callsite of the mocked function invocation. */ stack: Error; /** * If the mocked function is a constructor, this field contains the class being constructed. * Otherwise this will be `undefined`. */ target: F extends abstract new (...args: any) => any ? F : undefined; /** * The mocked function's `this` value. */ this: unknown; } interface MockFunctionContext { /** * A getter that returns a copy of the internal array used to track calls to the mock. */ readonly calls: Array>; /** * This function returns the number of times that this mock has been invoked. * This function is more efficient than checking `ctx.calls.length` * because `ctx.calls` is a getter that creates a copy of the internal call tracking array. */ callCount(): number; /** * This function is used to change the behavior of an existing mock. * @param implementation The function to be used as the mock's new implementation. */ mockImplementation(implementation: Function): void; /** * This function is used to change the behavior of an existing mock for a single invocation. * Once invocation `onCall` has occurred, the mock will revert to whatever behavior * it would have used had `mockImplementationOnce()` not been called. * @param implementation The function to be used as the mock's implementation for the invocation number specified by `onCall`. * @param onCall The invocation number that will use `implementation`. * If the specified invocation has already occurred then an exception is thrown. */ mockImplementationOnce(implementation: Function, onCall?: number): void; /** * Resets the call history of the mock function. */ resetCalls(): void; /** * Resets the implementation of the mock function to its original behavior. * The mock can still be used after calling this function. */ restore(): void; } export { test as default, run, test, describe, it, before, after, beforeEach, afterEach, mock }; }