Add type:"module" to package.json (#12272)

.eslintrc.cjs

@@ -7,6 +7,10 @@ module.exports = {
     es2021: true,
     node: true,
   },
+  parserOptions: {
+    ecmaVersion: "latest",
+    sourceType: "module",
+  },
   reportUnusedDisableDirectives: true,
   extends: ["eslint:recommended", "prettier"],
   plugins: [
@@ -87,7 +91,6 @@ module.exports = {
       },
     ],
     "require-await": "error",
-    strict: "error",
     "symbol-description": "error",
     yoda: [
       "error",
@@ -98,12 +101,13 @@ module.exports = {
     ],
 
     "import/extensions": ["error", "ignorePackages"],
-    "import/no-extraneous-dependencies": [
-      "error",
-      {
-        devDependencies: ["jest.config.mjs", "tests/**", "scripts/**"],
-      },
-    ],
+    // TODO[@fisker]: Fix this
+    // "import/no-extraneous-dependencies": [
+    //   "error",
+    //   {
+    //     devDependencies: ["jest.config.mjs", "tests/**", "scripts/**"],
+    //   },
+    // ],
     "import/order": "error",
     "import/no-anonymous-default-export": "error",
 
@@ -142,6 +146,8 @@ module.exports = {
     "unicorn/prefer-array-some": "error",
     "unicorn/prefer-includes": "error",
     "unicorn/prefer-json-parse-buffer": "error",
+    "unicorn/prefer-module": "error",
+    "unicorn/prefer-node-protocol": "error",
     "unicorn/prefer-number-properties": "error",
     "unicorn/prefer-optional-catch-binding": "error",
     "unicorn/prefer-regexp-test": "error",
@@ -155,6 +161,7 @@ module.exports = {
     {
       files: [
         "scripts/**/*.js",
+        "scripts/**/*.cjs",
         "scripts/**/*.mjs",
         "tests/config/install-prettier.js",
       ],
@@ -162,25 +169,33 @@ module.exports = {
         "no-console": "off",
       },
     },
+    // CommonJS modules
     {
       files: [
-        "**/*.mjs",
-        "scripts/release/**/*.js",
-        "tests/**/*.js",
-        "bin/**/*.js",
-        "src/cli/**/*.js",
-      ],
-      excludedFiles: [
+        "**/*.cjs",
+        "src/*.js",
+        "src/common/**/*.js",
+        "src/config/**/*.js",
+        "src/document/**/*.js",
+        "src/language-css/**/*.js",
+        "src/language-graphql/**/*.js",
+        "src/language-handlebars/**/*.js",
+        "src/language-html/**/*.js",
+        "src/language-js/**/*.js",
+        "src/language-markdown/**/*.js",
+        "src/language-yaml/**/*.js",
+        "src/main/**/*.js",
+        "src/utils/**/*.js",
+        "scripts/tools/eslint-plugin-prettier-internal-rules/**/*.js",
+        "website/**/*.js",
         "tests/integration/plugins/automatic/prettier-plugin-bar.js",
       ],
       parserOptions: {
-        sourceType: "module",
+        sourceType: "script",
       },
       rules: {
-        "unicorn/prefer-module": "error",
-        "unicorn/prefer-node-protocol": "error",
-        // TODO[@fisker]: Fix this
-        "import/no-extraneous-dependencies": "off",
+        strict: "error",
+        "unicorn/prefer-module": "off",
       },
     },
     // `esbuild` don't support
@@ -226,7 +241,6 @@ module.exports = {
     {
       files: ["tests/**/*.js"],
       rules: {
-        strict: "off",
         "import/no-extraneous-dependencies": "off",
         "unicorn/prefer-array-flat": "off",
         "unicorn/prefer-array-flat-map": "off",
@@ -329,5 +343,11 @@ module.exports = {
         sourceType: "module",
       },
     },
+    {
+      files: ["scripts/tools/eslint-plugin-prettier-internal-rules/**/*.js"],
+      rules: {
+        "import/no-extraneous-dependencies": "error",
+      },
+    },
   ],
 };

CONTRIBUTING.md

@@ -53,7 +53,7 @@ Parameters:
 
 The implementation of `run_spec` can be found in [`tests/config/format-test.js`](tests/config/format-test.js).
 
-`tests/format/flow-repo/` contains the Flow test suite and is not supposed to be edited by hand. To update it, clone the Flow repo next to the Prettier repo and run: `node scripts/sync-flow-tests.js ../flow/tests/`.
+`tests/format/flow-repo/` contains the Flow test suite and is not supposed to be edited by hand. To update it, clone the Flow repo next to the Prettier repo and run: `node scripts/sync-flow-tests.cjs ../flow/tests/`.
 
 ## Debugging
 

bin/package.json

@@ -1,3 +0,0 @@
-{
-  "type": "module"
-}

index.js

@@ -1,3 +1 @@
-"use strict";
-
-module.exports = require("./src/index.js");
+export { default } from "./src/index.js";

jest-format-test.config.mjs

@@ -4,7 +4,7 @@ const config = {
   ...baseConfig,
   runner: "./tests/config/jest-light-runner",
   testRegex: "tests/format/.*/jsfmt\\.spec\\.js$",
-  setupFiles: ["<rootDir>/tests/config/setup.js"],
+  setupFiles: ["<rootDir>/tests/config/format-test-setup.js"],
   projects: [],
 };
 

jest-integration-test.config.mjs

@@ -4,6 +4,10 @@ const config = {
   ...baseConfig,
   testRegex: "tests/integration/__tests__/.*\\.js$",
   projects: [],
+  moduleNameMapper: {
+    ...baseConfig.moduleNameMapper,
+    "prettier-local": "<rootDir>/tests/config/prettier-entry.common.cjs",
+  },
 };
 
 export default config;

jest.config.mjs

@@ -46,7 +46,7 @@ const config = {
   ],
   coverageReporters: ["text", "lcov"],
   moduleNameMapper: {
-    "prettier-local": "<rootDir>/tests/config/require-prettier.cjs",
+    "prettier-local": "<rootDir>/tests/config/prettier-entry.js",
     "prettier-standalone": "<rootDir>/tests/config/require-standalone.cjs",
   },
   modulePathIgnorePatterns: [

package.json

@@ -7,6 +7,7 @@
   "funding": "https://github.com/prettier/prettier?sponsor=1",
   "homepage": "https://prettier.io",
   "author": "James Long",
+  "type": "module",
   "license": "MIT",
   "main": "./index.js",
   "browser": "./standalone.js",

scripts/build-website.mjs

@@ -55,13 +55,14 @@ async function buildPlaygroundFiles() {
   const parsers = {};
   for (const fileName of files) {
     const file = path.join(PRETTIER_DIR, fileName);
-    await copyFile(file, path.join(PLAYGROUND_PRETTIER_DIR, fileName));
+    const dist = path.join(PLAYGROUND_PRETTIER_DIR, fileName);
+    await copyFile(file, dist);
 
     if (fileName === "standalone.js") {
       continue;
     }
 
-    const plugin = require(file);
+    const plugin = require(dist);
     // We add plugins to the global `prettierPlugins` object
     // the name after `parser-` is used as property
     // For example to get parsers in `parser-babel.js` via `prettierPlugins.babel`

scripts/build/build.mjs

@@ -164,6 +164,7 @@ async function preparePackage() {
   delete packageJson.dependencies;
   delete packageJson.devDependencies;
   delete packageJson.browserslist;
+  delete packageJson.type;
   packageJson.scripts = {
     prepublishOnly:
       "node -e \"assert.equal(require('.').version, require('..').version)\"",

scripts/build/bundler.mjs

@@ -49,10 +49,15 @@ function* getEsbuildOptions(bundle, buildOptions) {
   const replaceModule = {};
   // Replace other bundled files
   if (bundle.target === "node") {
-    // Replace package.json with dynamic `require("./package.json")`
+    // TODO[@fisker]: Fix this later, currently esbuild resolve it as ESM
+    // // Replace package.json with dynamic `require("./package.json")`
+    // replaceModule[path.join(PROJECT_ROOT, "package.json")] = {
+    //   path: "./package.json",
+    //   external: true,
+    // };
     replaceModule[path.join(PROJECT_ROOT, "package.json")] = {
-      path: "./package.json",
-      external: true,
+      contents: JSON.stringify({ version: packageJson.version }),
+      loader: "json",
     };
 
     // Dynamic require bundled files

scripts/generate-schema.mjs

@@ -1,7 +1,7 @@
 #!/usr/bin/env node
 
 import prettier from "../index.js";
-import generateSchema from "./utils/generate-schema.js";
+import generateSchema from "./utils/generate-schema.mjs";
 
 console.log(
   prettier.format(

scripts/sync-flow-tests.cjs

@@ -79,7 +79,7 @@ function run(argv) {
     console.error(
       [
         "You must provide the path to a flow tests directory to sync from!",
-        "Example: node scripts/sync-flow-tests.js ../flow/tests/",
+        "Example: node scripts/sync-flow-tests.cjs ../flow/tests/",
       ].join("\n")
     );
     return 1;

scripts/tools/eslint-plugin-prettier-internal-rules/package.json

@@ -3,6 +3,7 @@
   "version": "1.0.3",
   "description": "Prettier internal eslint rules",
   "private": true,
+  "type": "commonjs",
   "author": "fisker",
   "main": "./index.js",
   "license": "MIT",

scripts/utils/generate-schema.mjs

@@ -1,7 +1,3 @@
-"use strict";
-
-module.exports = generateSchema;
-
 function generateSchema(options) {
   return {
     $schema: "http://json-schema.org/draft-04/schema#",
@@ -116,3 +112,5 @@ function optionTypeToSchemaType(optionType) {
 function choiceToSchema(choice) {
   return { enum: [choice.value], description: choice.description };
 }
+
+export default generateSchema;

src/cli/package.json

@@ -1,3 +1,5 @@
 {
-  "type": "module"
+  "//TODO": "Remove this file when we close #10157",
+  "type": "module",
+  "description": "A package.json file to use `.js` files in this directory as ES module."
 }

src/package.json

@@ -0,0 +1,5 @@
+{
+  "//TODO": "Remove this file when we close #10157",
+  "type": "commonjs",
+  "description": "A package.json file to use `.js` files in this directory as CommonJS module."
+}

standalone.js

@@ -1,3 +1 @@
-"use strict";
-
-module.exports = require("./src/standalone.js");
+export { default } from "./src/standalone.js";

tests/config/format-test-setup.js

@@ -0,0 +1,19 @@
+import createEsmUtils from "esm-utils";
+import getPrettier from "./get-prettier.js";
+import runSpec from "./format-test.js";
+
+async function setup() {
+  const { TEST_STANDALONE } = process.env;
+
+  const prettier = TEST_STANDALONE
+    ? createEsmUtils(import.meta).require("./require-standalone.cjs")
+    : await getPrettier();
+
+  runSpec.prettier = prettier;
+
+  globalThis.run_spec = runSpec;
+}
+
+// `await`ed in `./jest-light-runner/worker-runner.js`
+// Use top-level await in `./prettier-entry.js` when we drop support for Node.js 12
+export { setup };

tests/config/format-test.js

@@ -8,12 +8,9 @@ import visualizeEndOfLine from "./utils/visualize-end-of-line.js";
 import consistentEndOfLine from "./utils/consistent-end-of-line.js";
 import stringifyOptionsForTitle from "./utils/stringify-options-for-title.js";
 
-const { require, __dirname } = createEsmUtils(import.meta);
+const { __dirname } = createEsmUtils(import.meta);
 
-const { TEST_STANDALONE } = process.env;
-const prettier = !TEST_STANDALONE
-  ? require("./require-prettier.cjs")
-  : require("./require-standalone.cjs");
+let prettier;
 
 const { FULL_TEST } = process.env;
 const BOM = "\uFEFF";
@@ -454,4 +451,13 @@ function format(originalText, originalOptions) {
   };
 }
 
+Object.defineProperty(runSpec, "prettier", {
+  get() {
+    return prettier;
+  },
+  set(prettierModule) {
+    prettier = prettierModule;
+  },
+  configurable: true,
+});
 export default runSpec;

tests/config/get-prettier.js

@@ -0,0 +1,12 @@
+import { pathToFileURL } from "node:url";
+import path from "node:path";
+
+const entry = pathToFileURL(path.join(process.env.PRETTIER_DIR, "index.js"));
+
+const getPrettier = async () => {
+  const { default: prettier } = await import(entry);
+
+  return prettier;
+};
+
+export default getPrettier;

tests/config/jest-light-runner/src/worker-runner.js

@@ -28,7 +28,11 @@ export default async function ({ test, updateSnapshot, port }) {
 
   const {setupFiles, snapshotSerializers} = test.context.config;
   for (const path of setupFiles) {
-    await import(pathToFileURL(path));
+    const { setup } = await import(pathToFileURL(path));
+
+    if (typeof setup === "function") {
+      await setup();
+    }
   }
   for (const path of snapshotSerializers) {
     const {default: serializer} = await import(pathToFileURL(path));

tests/config/prettier-entry.common.cjs

@@ -0,0 +1,7 @@
+"use strict";
+
+// This file exists because plugins for test use `require('prettier-local')`
+
+const path = require("path");
+
+module.exports = require(path.join(process.env.PRETTIER_DIR, "index.js"));

tests/config/prettier-entry.js

@@ -0,0 +1,3 @@
+import getPrettier from "./get-prettier.js";
+
+export default await getPrettier();

tests/config/require-prettier.cjs

@@ -1,5 +0,0 @@
-"use strict";
-
-const prettier = require(process.env.PRETTIER_DIR);
-
-module.exports = prettier;

tests/config/setup.js

@@ -1,3 +0,0 @@
-import run_spec from "./format-test.js";
-
-globalThis.run_spec = run_spec;

tests/format/js/cursor/jsfmt.spec.js

@@ -1,4 +1,6 @@
-import prettier from "../../../config/require-prettier.cjs";
+// TODO: Use this when we drop support for Node.js 12
+// import prettier from "../../../config/prettier-entry.js";
+const { prettier } = run_spec;
 
 run_spec(import.meta, ["babel", "typescript", "flow"]);
 

tests/format/misc/empty/jsfmt.spec.js

@@ -1,4 +1,4 @@
-import prettier from "../../../config/require-prettier.cjs";
+import prettier from "../../../../index.js";
 
 const parsers = prettier
   .getSupportInfo()

tests/integration/__tests__/schema.js

@@ -1,5 +1,5 @@
 import prettier from "prettier-local";
-import generateSchema from "../../../scripts/utils/generate-schema.js";
+import generateSchema from "../../../scripts/utils/generate-schema.mjs";
 
 test("schema", () => {
   expect(generateSchema(prettier.getSupportInfo().options)).toMatchSnapshot();

tests/package.json

@@ -1,3 +0,0 @@
-{
-  "type": "module"
-}

vendors/package.json

@@ -0,0 +1,5 @@
+{
+  "//TODO": "Remove this file when we close #10157",
+  "type": "commonjs",
+  "description": "A package.json file to use `.js` files in this directory as CommonJS module."
+}

website/package.json

@@ -1,4 +1,5 @@
 {
+  "private": true,
   "license": "MIT",
   "scripts": {
     "build": "webpack --mode=production && docusaurus-build",