test-repo/jest.config.js

import path from "node:path";
import createEsmUtils from "esm-utils";
import installBrowser from "./tests/config/install-browser.js";
import installPrettier from "./tests/config/install-prettier.js";

const { dirname: PROJECT_ROOT } = createEsmUtils(import.meta);
const isProduction = process.env.NODE_ENV === "production";
// Disabled https://github.com/nicolo-ribaudo/jest-light-runner/pull/13
// const ENABLE_CODE_COVERAGE = Boolean(process.env.ENABLE_CODE_COVERAGE);
const TEST_STANDALONE = Boolean(process.env.TEST_STANDALONE);
const INSTALL_PACKAGE = Boolean(process.env.INSTALL_PACKAGE);
const TEST_RUNTIME = process.env.TEST_RUNTIME ?? "nodejs";
// When debugging production test, this flag can skip installing package
const SKIP_PRODUCTION_INSTALL = Boolean(process.env.SKIP_PRODUCTION_INSTALL);
const nodejsMajorVersion = Number(process.versions.node.split(".")[0]);

let PRETTIER_DIR = isProduction
  ? path.join(PROJECT_ROOT, "dist/prettier")
  : PROJECT_ROOT;
let PRETTIER_INSTALLED_DIR = "";
if (
  INSTALL_PACKAGE ||
  (isProduction &&
    !TEST_STANDALONE &&
    !SKIP_PRODUCTION_INSTALL &&
    TEST_RUNTIME === "nodejs")
) {
  PRETTIER_INSTALLED_DIR = installPrettier(PRETTIER_DIR);
  PRETTIER_DIR = path.join(PRETTIER_INSTALLED_DIR, "node_modules/prettier");
}
if (TEST_RUNTIME === "browser") {
  installBrowser();
}
process.env.PRETTIER_INSTALLED_DIR = PRETTIER_INSTALLED_DIR;
process.env.PRETTIER_DIR = PRETTIER_DIR;

const testPathIgnorePatterns = [];
if (TEST_STANDALONE || TEST_RUNTIME !== "nodejs") {
  testPathIgnorePatterns.push("tests/integration/");
}
if (isProduction) {
  // Only run unit test for development
  testPathIgnorePatterns.push("tests/unit/");
} else {
  // Only test bundles for production
  testPathIgnorePatterns.push("tests/integration/__tests__/bundle.js");
}

// Currently can't load plugins in browser
if (TEST_RUNTIME === "browser") {
  testPathIgnorePatterns.push(
    "tests/format/misc/front-matter/with-plugins/format.test.js",
    "tests/format/misc/plugins/embed-async-printer/format.test.js",
    "tests/format/misc/errors/broken-plugin/format.test.js",
    "tests/format/vue/with-plugins/format.test.js",
    "tests/format/misc/plugins/async-printer/format.test.js",
    "tests/format/handlebars/front-matter/toml/format.test.js",
    "tests/format/markdown/broken-plugins/format.test.js",
    "tests/format/vue/broken-plugins/format.test.js",
  );
}

if (nodejsMajorVersion <= 18) {
  // Uses import attributes and `Array#toSorted()`
  testPathIgnorePatterns.push("tests/integration/__tests__/help-options.js");
}

if (nodejsMajorVersion <= 14) {
  testPathIgnorePatterns.push(
    "tests/integration/__tests__/plugin-parsers.js",
    "tests/integration/__tests__/normalize-doc.js",
    "tests/integration/__tests__/doc-utilities-clean-doc.js",
    "tests/integration/__tests__/config-invalid.js",
    // `@prettier/cli` uses `node:stream/consumers`, not available on Node.js v14
    "tests/integration/__tests__/experimental-cli.js",
    // Fails on Node.js v14
    "tests/dts/unit/run.js",
  );
}

const config = {
  setupFiles: [
    "<rootDir>/tests/config/format-test-setup.js",
    "<rootDir>/tests/integration/integration-test-setup.js",
  ],
  runner: "jest-light-runner/child-process",
  testEnvironmentOptions: {
    customExportConditions: ["development"],
  },
  snapshotSerializers: [
    "jest-snapshot-serializer-raw",
    "jest-snapshot-serializer-ansi",
  ],
  testMatch: [
    "<rootDir>/tests/format/**/format.test.js",
    "<rootDir>/tests/integration/__tests__/**/*.js",
    "<rootDir>/tests/unit/**/*.js",
    "<rootDir>/tests/dts/unit/**/*.js",
  ],
  testPathIgnorePatterns: testPathIgnorePatterns.map(
    (file) => `<rootDir>/${file}`,
  ),
  // collectCoverage: ENABLE_CODE_COVERAGE,
  collectCoverageFrom: ["<rootDir>/src/**/*.js", "<rootDir>/bin/**/*.js"],
  coveragePathIgnorePatterns: [
    "<rootDir>/src/standalone.js",
    "<rootDir>/src/document/debug.js",
  ],
  coverageReporters: ["text", "lcov"],
  moduleNameMapper: {
    "prettier-local": "<rootDir>/tests/config/prettier-entry.js",
    "prettier-standalone": "<rootDir>/tests/config/require-standalone.cjs",
  },
  modulePathIgnorePatterns: [
    "<rootDir>/dist",
    "<rootDir>/website",
    "<rootDir>/scripts/release",
  ],
  transform: {},
  watchPlugins: [
    "jest-watch-typeahead/filename",
    "jest-watch-typeahead/testname",
  ],
};

export default config;