TypeScriptでJestを使うための設定
インストール
TypeScriptがインストール済みの場合、jest、@types/jest、ts-jestをインストールします。
npm install --save-dev jest @types/jest ts-jest
設定ファイル (tsconfig.json)
以下を実行すると、いくつか質問があります。 それらに回答すると、jest.config.tsファイルが作成されます。
npx jest --init
以下でも可能です。
./node_modules/.bin/jest --init
例 全て No で回答
npx jest --init The following questions will help Jest to create a suitable configuration for your project ✔ Would you like to use Typescript for the configuration file? … no ✔ Choose the test environment that will be used for testing › node ✔ Do you want Jest to add coverage reports? … no ✔ Which provider should be used to instrument code for coverage? › v8 ✔ Automatically clear mock calls and instances between every test? … no �� Configuration file created at /home/vagrant/git/prog/js/ts/basic/jest.config.js注意 最初の質問は、Jestの設定ファイルをtsファイルにするか、jsファイルにするかの質問です。
サンプル
jsファイルの場合、ファイル名は jest.config.jsで、中身は以下のようになります。
/* * For a detailed explanation regarding each configuration property, visit: * https://jestjs.io/docs/configuration */ module.exports = { // 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: "/tmp/jest_rs", // Automatically clear mock calls and instances between every test // clearMocks: false, // 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: undefined, // 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: "v8", // 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: {}, // 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", // "jsx", // "ts", // "tsx", // "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 // 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 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: [ // "**/__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: "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: undefined, // An array of regexp pattern strings that are matched against all source file paths, matched files will skip transformation // transformIgnorePatterns: [ // "/node_modules/", // "\\.pnp\\.[^\\/]+$" // ], // 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, };