jest.config.ts

import type { Config } from "@jest/types";

export default async (): Promise<Config.InitialOptions> => {
  return {
    // The root of your source code, typically /src
    // `<rootDir>` is a token Jest substitutes
    roots: ["<rootDir>/src"],

    // Jest transformations -- this adds support for TypeScript
    // using ts-jest
    transform: {
      "^.+\\.tsx?$": "ts-jest",
    },

    // Runs special logic, such as cleaning up components
    // when using React Testing Library and adds special
    // extended assertions to Jest
    setupFilesAfterEnv: [
      // "@testing-library/react/cleanup-after-each",
      "@testing-library/jest-dom/extend-expect",
      "jest-canvas-mock",
    ],

    // Test spec file resolution pattern
    // Matches parent folder `__tests__` and filename
    // should contain `test` or `spec`.
    testRegex: "(/__tests__/.*|(\\.|/)(test|spec))\\.tsx?$",

    // Module file extensions for importing
    moduleFileExtensions: ["ts", "tsx", "js", "jsx", "json", "node"],

    // All imported modules in your tests should be mocked automatically
    // automock: false,

    // Stop running tests after `n` failures
    // bail: 0,

    // The directory where Jest should store its cached dependency information
    // cacheDirectory: "/private/var/folders/t5/3rr3f6y11j33hb3zrmm66nh80000gn/T/jest_dx",

    // Automatically clear mock calls and instances between every test
    // clearMocks: true,

    // Indicates whether the coverage information should be collected while executing the test
    // collectCoverage: false,

    // An array of glob patterns indicating a set of files for which coverage information should be collected
    // collectCoverageFrom: undefined,

    // The directory where Jest should output its coverage files
    coverageDirectory: "coverage",

    // An array of regexp pattern strings used to skip coverage collection
    // coveragePathIgnorePatterns: [
    //   "/node_modules/"
    // ],

    // A list of reporter names that Jest uses when writing coverage reports
    // coverageReporters: [
    //   "json",
    //   "text",
    //   "lcov",
    //   "clover"
    // ],

    // An object that configures minimum threshold enforcement for coverage results
    // coverageThreshold: undefined,

    // A path to a custom dependency extractor
    // dependencyExtractor: undefined,

    // Make calling deprecated APIs throw helpful error messages
    // errorOnDeprecated: false,

    // Force coverage collection from ignored files using an array of glob patterns
    // forceCoverageMatch: [],

    // A path to a module which exports an async function that is triggered once before all test suites
    // globalSetup: undefined,

    // A path to a module which exports an async function that is triggered once after all test suites
    // globalTeardown: undefined,

    // A set of global variables that need to be available in all test environments
    globals: {
      "ts-jest": {
        diagnostics: false,
      },
    },

    // The maximum amount of workers used to run your tests. Can be specified as % or a number. E.g. maxWorkers: 10% will use 10% of your CPU amount + 1 as the maximum worker number. maxWorkers: 2 will use a maximum of 2 workers.
    // maxWorkers: "50%",

    // An array of directory names to be searched recursively up from the requiring module's location
    // moduleDirectories: [
    //   "node_modules"
    // ],

    // An array of file extensions your modules use
    // moduleFileExtensions: [
    //   "js",
    //   "json",
    //   "jsx",
    //   "ts",
    //   "tsx",
    //   "node"
    // ],

    // A map from regular expressions to module names or to arrays of module names that allow to stub out resources with a single module
    // moduleNameMapper: {},

    // An array of regexp pattern strings, matched against all module paths before considered 'visible' to the module loader
    // modulePathIgnorePatterns: [],

    // Activates notifications for test results
    // notify: false,

    // An enum that specifies notification mode. Requires { notify: true }
    // notifyMode: "failure-change",

    // A preset that is used as a base for Jest's configuration
    // preset: undefined,

    // Run tests from one or more projects
    // projects: undefined,

    // Use this configuration option to add custom reporters to Jest
    // reporters: undefined,

    // Automatically reset mock state between every test
    // resetMocks: false,

    // Reset the module registry before running each individual test
    // resetModules: false,

    // A path to a custom resolver
    // resolver: undefined,

    // Automatically restore mock state between every test
    // restoreMocks: false,

    // The root directory that Jest should scan for tests and modules within
    // rootDir: undefined,

    // A list of paths to directories that Jest should use to search for files in
    // roots: [
    //   "<rootDir>"
    // ],

    // Allows you to use a custom runner instead of Jest's default test runner
    // runner: "jest-runner",

    // The paths to modules that run some code to configure or set up the testing environment before each test
    // setupFiles: [],

    // A list of paths to snapshot serializer modules Jest should use for snapshot testing
    // snapshotSerializers: [],

    // The test environment that will be used for testing
    // testEnvironment: "jest-environment-jsdom",

    // Options that will be passed to the testEnvironment
    // testEnvironmentOptions: {},

    // Adds a location field to test results
    // testLocationInResults: false,

    // The glob patterns Jest uses to detect test files
    // testMatch: [
    //   "**/__tests__/**/*.[jt]s?(x)",
    //   "**/?(*.)+(spec|test).[tj]s?(x)"
    // ],

    // An array of regexp pattern strings that are matched against all test paths, matched tests are skipped
    // testPathIgnorePatterns: [
    //   "/node_modules/"
    // ],

    // The regexp pattern or array of patterns that Jest uses to detect test files
    // testRegex: [],

    // This option allows the use of a custom results processor
    // testResultsProcessor: undefined,

    // This option allows use of a custom test runner
    // testRunner: "jasmine2",

    // This option sets the URL for the jsdom environment. It is reflected in properties such as location.href
    // testURL: "http://localhost",

    // Setting this value to "fake" allows the use of fake timers for functions such as "setTimeout"
    // timers: "real",

    // A map from regular expressions to paths to transformers
    // transform: undefined,

    // An array of regexp pattern strings that are matched against all source file paths, matched files will skip transformation
    // transformIgnorePatterns: [
    //   "/node_modules/"
    // ],

    // An array of regexp pattern strings that are matched against all modules before the module loader will automatically return a mock for them
    // unmockedModulePathPatterns: undefined,

    // Indicates whether each individual test should be reported during the run
    // verbose: undefined,

    // An array of regexp patterns that are matched against all source file paths before re-running tests in watch mode
    // watchPathIgnorePatterns: [],

    // Whether to use watchman for file crawling
    // watchman: true,
  };
};