feat(puppeteer): export esm modules in package.json

Signed-off-by: Randolf Jung <jrandolf@chromium.org>

compat/README.md

@@ -0,0 +1,16 @@
+# Compatibility layer
+
+This directory provides an additional compatibility layer between ES modules and CommonJS.
+
+## Why?
+
+Both `./cjs/compat.ts` and `./esm/compat.ts` are written as ES modules, but `./cjs/compat.ts` can additionally use NodeJS CommonJS globals such as `__dirname` and `require` while these are disabled in ES module mode. For more information, see [Differences between ES modules and CommonJS](https://nodejs.org/api/esm.html#differences-between-es-modules-and-commonjs).
+
+## Adding exports
+
+In order to add exports, two things need to be done:
+
+- The exports must be declared in `src/compat.ts`.
+- The exports must be realized in `./cjs/compat.ts` and `./esm/compat.ts`.
+
+In the event `compat.ts` becomes too large, you can place declarations in another file. Just make sure `./cjs`, `./esm`, and `src` have the same structure.

compat/cjs/compat.ts

@@ -0,0 +1 @@
+export const puppeteerDirname = __dirname;

compat/cjs/tsconfig.json

@@ -0,0 +1,11 @@
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "composite": true,
+    "outDir": "../../lib/cjs/puppeteer",
+    "module": "CommonJS"
+  },
+  "references": [
+    { "path": "../../vendor/tsconfig.cjs.json"}
+  ]
+}

compat/esm/compat.ts

@@ -0,0 +1,4 @@
+import { dirname } from 'path';
+import { fileURLToPath } from 'url';
+
+export const puppeteerDirname = dirname(fileURLToPath(import.meta.url));

compat/esm/tsconfig.json

@@ -0,0 +1,9 @@
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "composite": true,
+    "outDir": "../../lib/esm/puppeteer",
+    "module": "esnext"
+  },
+  "references": [{ "path": "../../vendor/tsconfig.esm.json" }]
+}

package.json

@@ -2,7 +2,12 @@
   "name": "puppeteer",
   "version": "13.2.0",
   "description": "A high-level API to control headless Chrome over the DevTools Protocol",
+  "type": "commonjs",
   "main": "./cjs-entry.js",
+  "exports": {
+    "import": "./lib/esm/puppeteer/node.js",
+    "require": "./cjs-entry.js"
+  },
   "types": "lib/types.d.ts",
   "repository": "github:puppeteer/puppeteer",
   "engines": {
@@ -29,15 +34,18 @@
     "lint": "npm run eslint && npm run build && npm run doc && npm run markdownlint",
     "doc": "node utils/doclint/cli.js",
     "clean-lib": "rimraf lib",
-    "build": "npm run tsc && npm run generate-d-ts",
-    "tsc": "npm run clean-lib && tsc --version && npm run tsc-cjs && npm run tsc-esm",
+    "build": "npm run tsc && npm run generate-d-ts && npm run generate-pkg-json",
+    "tsc": "npm run clean-lib && tsc --version && (npm run tsc-cjs & npm run tsc-esm) && (npm run tsc-compat-cjs & npm run tsc-compat-esm)",
     "tsc-cjs": "tsc -b src/tsconfig.cjs.json",
     "tsc-esm": "tsc -b src/tsconfig.esm.json",
+    "tsc-compat-cjs": "tsc -b compat/cjs/tsconfig.json",
+    "tsc-compat-esm": "tsc -b compat/esm/tsconfig.json",
     "apply-next-version": "node utils/apply_next_version.js",
     "test-install": "scripts/test-install.sh",
     "clean-docs": "rimraf website/docs && rimraf docs-api-json",
     "generate-d-ts": "npm run clean-docs && api-extractor run --local --verbose",
     "generate-docs": "npm run generate-d-ts && api-documenter markdown -i docs-api-json -o website/docs && node utils/remove-tag.js",
+    "generate-pkg-json": "echo '{\"type\": \"module\"}' > lib/esm/package.json",
     "ensure-correct-devtools-protocol-revision": "ts-node -s scripts/ensure-correct-devtools-protocol-package",
     "ensure-pinned-deps": "ts-node -s scripts/ensure-pinned-deps",
     "test-types-file": "ts-node -s scripts/test-ts-definition-files.ts",

src/common/Debug.ts

@@ -55,7 +55,9 @@ import { isNode } from '../environment.js';
 export const debug = (prefix: string): ((...args: unknown[]) => void) => {
   if (isNode) {
     // eslint-disable-next-line @typescript-eslint/no-var-requires
-    return require('debug')(prefix);
+    return async (...logArgs: unknown[]) => {
+      (await import('debug')).default(prefix)(logArgs);
+    };
   }
 
   return (...logArgs: unknown[]): void => {

src/compat.ts

@@ -0,0 +1,3 @@
+declare const puppeteerDirname: string;
+
+export { puppeteerDirname };

src/initialize-node.ts

@@ -18,9 +18,10 @@ import { PuppeteerNode } from './node/Puppeteer.js';
 import { PUPPETEER_REVISIONS } from './revisions.js';
 import pkgDir from 'pkg-dir';
 import { Product } from './common/Product.js';
+import { puppeteerDirname } from './compat.js';
 
 export const initializePuppeteerNode = (packageName: string): PuppeteerNode => {
-  const puppeteerRootDirectory = pkgDir.sync(__dirname);
+  const puppeteerRootDirectory = pkgDir.sync(puppeteerDirname);
 
   let preferredRevision = PUPPETEER_REVISIONS.chromium;
   const isPuppeteerCore = packageName === 'puppeteer-core';

tsconfig.json

@@ -12,5 +12,5 @@
      */
     "module": "esnext"
   },
-  "include": ["src"]
+  "include": ["src"],
 }