jest.config.mjs

import * as fs from 'fs/promises';
import * as path from 'path';
import * as url from 'url';
/*
 * For a detailed explanation regarding each configuration property, visit:
 * https://jestjs.io/docs/configuration
 */
const tsconfig = JSON.parse(
  (
    await fs.readFile(
      path.join(path.dirname(url.fileURLToPath(import.meta.url)), 'tsconfig.json'),
      'utf8',
    )
  ).replace(/\/\*.*\*\//g, ''),
);

const pathsToModuleNameMapper = (pathMap) =>
  Object.fromEntries(
    Object.entries(pathMap).map(([key, paths]) => {
      if (paths.length !== 1) throw new Error('dunno what to do');

      let prefix = process.cwd();
      // go up to the root of the monorepo
      if (prefix.includes('packages')) prefix = path.join(prefix, '..', '..');

      const regexKey = `^${key.replace(/\*$/, '(.*?)(\\.js)?')}$`;
      const remappedPath = path.join(prefix, paths[0].replace(/\*$/, '$1'));
      return [regexKey, remappedPath];
    }),
  );

export default {
  // 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/46/ysxpl3s947l59zlrydtlsgq00000gn/T/jest_dx",

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

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

  // An array of glob patterns indicating a set of files for which coverage information should be collected
  collectCoverageFrom: ['src/**/*.{js,jsx,ts,tsx}', '!src/**/*.test.ts'],

  // 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/"
  // ],

  // Indicates which provider should be used to instrument code for coverage
  // coverageProvider: "babel",

  // 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: '<rootDir>/jest.setup.mjs',

  // 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: {},

  // 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: ['ts', 'js', 'mjs', 'cjs', 'json', '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

  // 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: 'ts-jest',

  // 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 before every test
  resetMocks: true,

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

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

  // Automatically restore mock state and implementation before every test
  // restoreMocks: false,

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

  // 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 modules that run some code to configure or set up the testing framework before each test
  // setupFilesAfterEnv: [],

  // The number of seconds after which a test is considered as slow and reported as such in the results.
  // slowTestThreshold: 5,

  // 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-node",

  // 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: ['**/?(*.)+(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: "jest-circus/runner",

  // 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: {
    '^.+\\.(t|j)sx?$': [
      '@swc/jest',
      {
        jsc: {
          // baseUrl: '.',
          // paths: {
          //   '@/shared/*': ['./packages/shared/src/*'],
          // },
          parser: {
            syntax: 'typescript',
            tsx: false,
            decorators: true,
          },
          transform: {
            legacyDecorator: true,
            decoratorMetadata: true,
          },
        },
      },
    ],
  },

  moduleNameMapper: {
    ...pathsToModuleNameMapper(tsconfig.compilerOptions.paths),
  },

  // An array of regexp pattern strings that are matched against all source file paths, matched files will skip transformation
  transformIgnorePatterns: ['/node_modules/.pnpm/(?!(superjson))'],

  // 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,
};