/**
 * The `node:test` module provides a standalone testing module.
 * @see [source](https://github.com/nodejs/node/blob/v16.17.0/lib/test.js)
 */
declare module "node:test" {
    /**
     * 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 v16.17.0
     * @param name The name of the test, which is displayed when reporting test results.
     *    Default: The `name` property of fn, or `'<anonymous>'` 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<void>;
    function test(name?: string, options?: TestOptions, fn?: TestFn): Promise<void>;
    function test(options?: TestOptions, fn?: TestFn): Promise<void>;
    function test(fn?: TestFn): Promise<void>;

    /*
     * @since v16.17.0
     * @param name The name of the suite, which is displayed when reporting suite results.
     *    Default: The `name` property of fn, or `'<anonymous>'` 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;

    /*
     * @since v16.17.0
     * @param name The name of the test, which is displayed when reporting test results.
     *    Default: The `name` property of fn, or `'<anonymous>'` 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;

    /**
     * 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;

    /**
     * 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 v16.17.0
     */
    interface TestContext {
        /**
         * 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 v16.17.0
         */
        diagnostic(message: string): void;

        /**
         * 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 v16.17.0
         */
        runOnly(shouldRunOnlyTests: boolean): void;

        /**
         * 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 v16.17.0
         */
        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 v16.17.0
         */
        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 v16.17.0
         * @param name The name of the test, which is displayed when reporting test results.
         *    Default: The `name` property of fn, or `'<anonymous>'` 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;
    }

    interface TestOptions {
        /**
         * The number of tests that can be run at the same time. If unspecified, subtests inherit this
         * value from their parent.
         * @default 1
         */
        concurrency?: number;

        /**
         * 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;

        /**
         * Allows aborting an in-progress test.
         * @since v16.17.0
         */
        signal?: AbortSignal;

        /**
         * 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;

        /**
         * A number of milliseconds the test will fail after. If unspecified, subtests inherit this
         * value from their parent.
         * @default Infinity
         * @since v16.17.0
         */
        timeout?: number;

        /**
         * 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;
    }

    export { describe, it, test, test as default };
}
