fix: wider compat TS types and CI checks to ensure correct type defs (#…

…6855)

* fix: wider compat TS types and CI checks to ensure correct type defs

This PR improves our TS types further to make sure they are usable in a
TS environment where ES Modules are the target output. Our use of
`export =` is problematic this environment as TypeScript does not allow
`export =` to be used and it errors.

The fix for the type issues to avoid `export =` is to instead define the
functions that you gain access to when you import Puppeteer as top level
functions in our `types.d.ts` file. We can do this by declaring them
explicitly in `src/node.ts`. These are then rolled into `lib/types.d.ts`
at build time. The downside to this is that we have to keep those
declarations in sync with the Puppeteer API; should we add a new method
to the `Puppeteer` class, we must add it to the `nodes.ts` declarations.
However, this could easily be automated by a small script that walks the
AST and generates these. I will do that in a follow-up PR, but I
consider this low risk given how rarely the very top level API of
Puppeteer changes. The nice thing about this approach is we no longer
need our script that hacks on changes to `lib/types.d.ts`.

To avoid yet more releases to fix issues in one particular TS
environment, this PR also includes a suite of example setups that we
test on each CI run. Each sample folder contains `good.ts`, which should
have no TS errors, and `bad.ts`, which should have some errors. The test
first packs Puppeteer into a tar, and then installs it from that tar
into each project. This should replicate how the published package
behaves when it is installed. We then check that we get no errors on
`good.ts`, and the expected errors on `bad.ts`.

We have a variety of test projects that cover both TS and JS source
code, and CJS and ESM imports and outputs.

.eslintignore

@@ -12,3 +12,4 @@ lib/
 utils/doclint/generate_types/test/test.ts
 vendor/
 web-test-runner.config.mjs
+test-ts-types/

.github/workflows/main.yml

@@ -45,6 +45,7 @@ jobs:
           npm run lint
           npm run generate-docs
           npm run ensure-correct-devtools-protocol-revision
+          npm run test-types-file
 
       - name: Run unit tests
         env:

.github/workflows/publish-on-tag.yml

@@ -3,7 +3,7 @@ name: publish-on-tag
 on:
   push:
     tags:
-    - '*'
+      - '*'
 
 jobs:
   publish:

.gitignore

@@ -1,4 +1,6 @@
 /node_modules/
+test-ts-types/**/node_modules
+test-ts-types/**/dist/
 /test/output-chromium
 /test/output-firefox
 /test/test-user-data-dir*
@@ -18,3 +20,4 @@ test/coverage.json
 temp/
 puppeteer-core-*.tgz
 new-docs/
+puppeteer-*.tgz

package.json

@@ -33,9 +33,10 @@
     "tsc-esm": "tsc -b src/tsconfig.esm.json",
     "apply-next-version": "node utils/apply_next_version.js",
     "test-install": "scripts/test-install.sh",
-    "generate-d-ts": "npm run tsc && api-extractor run --local --verbose && ts-node -s scripts/add-default-export-to-types.ts",
+    "generate-d-ts": "api-extractor run --local --verbose",
     "generate-docs": "npm run generate-d-ts && api-documenter markdown -i temp -o new-docs",
     "ensure-correct-devtools-protocol-revision": "ts-node -s scripts/ensure-correct-devtools-protocol-package",
+    "test-types-file": "ts-node -s scripts/test-ts-definition-files.ts",
     "release": "node utils/remove_version_suffix.js && standard-version --commit-all"
   },
   "files": [

scripts/test-ts-definition-files.ts

@@ -0,0 +1,187 @@
+import { spawnSync } from 'child_process';
+import { version } from '../package.json';
+import path from 'path';
+const PROJECT_FOLDERS_ROOT = 'test-ts-types';
+const EXPECTED_ERRORS = new Map<string, string[]>([
+  [
+    'ts-esm-import-esm-output',
+    [
+      "bad.ts(6,35): error TS2551: Property 'launh' does not exist on type",
+      "bad.ts(8,29): error TS2551: Property 'devics' does not exist on type",
+      'bad.ts(12,39): error TS2554: Expected 0 arguments, but got 1.',
+    ],
+  ],
+  [
+    'ts-esm-import-cjs-output',
+    [
+      "bad.ts(6,35): error TS2551: Property 'launh' does not exist on type",
+      "bad.ts(8,29): error TS2551: Property 'devics' does not exist on type",
+      'bad.ts(12,39): error TS2554: Expected 0 arguments, but got 1.',
+    ],
+  ],
+  [
+    'ts-cjs-import-cjs-output',
+    [
+      "bad.ts(5,35): error TS2551: Property 'launh' does not exist on type",
+      "bad.ts(7,29): error TS2551: Property 'devics' does not exist on type",
+      'bad.ts(11,39): error TS2554: Expected 0 arguments, but got 1.',
+    ],
+  ],
+  [
+    'js-esm-import-cjs-output',
+    [
+      "bad.js(5,35): error TS2551: Property 'launh' does not exist on type",
+      "bad.js(7,29): error TS2551: Property 'devics' does not exist on type",
+      'bad.js(11,39): error TS2554: Expected 0 arguments, but got 1.',
+      "bad.js(15,9): error TS2322: Type 'ElementHandle<Element> | null' is not assignable to type 'ElementHandle<HTMLElement>'",
+    ],
+  ],
+  [
+    'js-cjs-import-esm-output',
+    [
+      "bad.js(5,35): error TS2551: Property 'launh' does not exist on type",
+      "bad.js(7,29): error TS2551: Property 'devics' does not exist on type",
+      'bad.js(11,39): error TS2554: Expected 0 arguments, but got 1.',
+      "bad.js(15,9): error TS2322: Type 'ElementHandle<Element> | null' is not assignable to type 'ElementHandle<HTMLElement>'",
+    ],
+  ],
+  [
+    'js-esm-import-esm-output',
+    [
+      "bad.js(5,35): error TS2551: Property 'launh' does not exist on type",
+      "bad.js(7,29): error TS2551: Property 'devics' does not exist on type",
+      'bad.js(11,39): error TS2554: Expected 0 arguments, but got 1.',
+      "bad.js(15,9): error TS2322: Type 'ElementHandle<Element> | null' is not assignable to type 'ElementHandle<HTMLElement>'",
+    ],
+  ],
+  [
+    'js-cjs-import-cjs-output',
+    [
+      "bad.js(5,35): error TS2551: Property 'launh' does not exist on type",
+      "bad.js(7,29): error TS2551: Property 'devics' does not exist on type",
+      'bad.js(11,39): error TS2554: Expected 0 arguments, but got 1.',
+      "bad.js(15,9): error TS2322: Type 'ElementHandle<Element> | null' is not assignable to type 'ElementHandle<HTMLElement>'",
+    ],
+  ],
+]);
+const PROJECT_FOLDERS = [...EXPECTED_ERRORS.keys()];
+
+function packPuppeteer() {
+  console.log('Packing Puppeteer');
+  const result = spawnSync('npm', ['pack'], {
+    encoding: 'utf-8',
+  });
+
+  if (result.status !== 0) {
+    console.log('Failed to pack Puppeteer', result.stderr);
+    process.exit(1);
+  }
+
+  return `puppeteer-${version}.tgz`;
+}
+
+const tar = packPuppeteer();
+const tarPath = path.join(process.cwd(), tar);
+
+function compileAndCatchErrors(projectLocation) {
+  const { status, stdout, stderr } = spawnSync('npm', ['run', 'compile'], {
+    cwd: projectLocation,
+    encoding: 'utf-8',
+  });
+  const tsErrorMesssage = stdout.split('\n');
+
+  if (status === 0) {
+    console.error(
+      `Running tsc on ${projectLocation} succeeded without triggering the expected errors.`
+    );
+    console.log(stdout, stderr);
+    process.exit(1);
+  }
+
+  return {
+    tsErrorMesssage,
+  };
+}
+
+function testProject(folder: string) {
+  console.log('\nTesting:', folder);
+  const projectLocation = path.join(
+    process.cwd(),
+    PROJECT_FOLDERS_ROOT,
+    folder
+  );
+
+  const tarLocation = path.relative(projectLocation, tarPath);
+  console.log('===> Installing Puppeteer from tar file');
+  const { status, stderr, stdout } = spawnSync(
+    'npm',
+    ['install', '--no-package-lock', tarLocation],
+    {
+      env: {
+        PUPPETEER_SKIP_DOWNLOAD: '1',
+      },
+      cwd: projectLocation,
+      encoding: 'utf-8',
+    }
+  );
+
+  if (status > 0) {
+    console.error(
+      'Installing the tar file unexpectedly failed',
+      stdout,
+      stderr
+    );
+    process.exit(status);
+  }
+  console.log('===> Running compile to ensure expected errors only.');
+  const result = compileAndCatchErrors(projectLocation);
+  const expectedErrors = EXPECTED_ERRORS.get(folder) || [];
+  if (
+    result.tsErrorMesssage.find(
+      (line) => line.includes('good.ts') || line.includes('good.js')
+    )
+  ) {
+    console.error(
+      `Error for ${projectLocation} contained unexpected failures in good.ts/good.js:\n${result.tsErrorMesssage.join(
+        '\n'
+      )}`
+    );
+    process.exit(1);
+  }
+  const errorsInTsMessage = result.tsErrorMesssage.filter(
+    (line) => line.includes('bad.ts') || line.includes('bad.js')
+  );
+  const expectedErrorsThatHaveOccurred = new Set<string>();
+  const unexpectedErrors = errorsInTsMessage.filter((message) => {
+    const isExpected = expectedErrors.some((expectedError) => {
+      const isExpected = message.startsWith(expectedError);
+      if (isExpected) {
+        expectedErrorsThatHaveOccurred.add(expectedError);
+      }
+      return isExpected;
+    });
+    return !isExpected;
+  });
+
+  if (unexpectedErrors.length) {
+    console.error(
+      `${projectLocation} had unexpected TS errors: ${unexpectedErrors.join(
+        '\n'
+      )}`
+    );
+    process.exit(1);
+  }
+  expectedErrors.forEach((expected) => {
+    if (!expectedErrorsThatHaveOccurred.has(expected)) {
+      console.error(
+        `${projectLocation} expected error that was not thrown: ${expected}`
+      );
+      process.exit(1);
+    }
+  });
+  console.log('===> ✅ Type-checked correctly.');
+}
+
+PROJECT_FOLDERS.forEach((folder) => {
+  testProject(folder);
+});

src/api-docs-entry.ts

@@ -14,6 +14,16 @@
  * limitations under the License.
  */
 
+import { LaunchOptions, ChromeArgOptions } from './node/LaunchOptions.js';
+import { BrowserOptions } from './common/BrowserConnector.js';
+import { Product } from './common/Product.js';
+import { Browser } from './common/Browser.js';
+import { ConnectOptions } from './common/Puppeteer.js';
+import { DevicesMap } from './common/DeviceDescriptors.js';
+import { PuppeteerErrors } from './common/Errors.js';
+import { PredefinedNetworkConditions } from './common/NetworkConditions.js';
+import { CustomQueryHandler } from './common/QueryHandler.js';
+
 /*
  * This file re-exports any APIs that we want to have documentation generated
  * for. It is used by API Extractor to determine what parts of the system to
@@ -62,4 +72,75 @@ export * from './common/PDFOptions.js';
 export * from './common/TimeoutSettings.js';
 export * from './common/LifecycleWatcher.js';
 export * from './common/QueryHandler.js';
+export * from './common/NetworkConditions.js';
 export * from 'devtools-protocol/types/protocol';
+
+/*
+ * We maintain a namespace that emulates the API of the Puppeteer instance you
+ * get when you `import puppeteer from 'puppeteer'.
+ *
+ * We do this as a namespace because export = PuppeteerDefault where
+ * PuppeteerDefault is a namespace seems to make sure that the types work in
+ * both ESM and CJS contexts.
+ *
+ * This namespace must be kept in sync with the public API offered by the
+ * PuppeteerNode class.
+ */
+
+/**
+ * @public
+ * {@inheritDoc PuppeteerNode.launch}
+ */
+export declare function launch(
+  options?: LaunchOptions &
+    ChromeArgOptions &
+    BrowserOptions & {
+      product?: Product;
+      extraPrefsFirefox?: Record<string, unknown>;
+    }
+): Promise<Browser>;
+
+/**
+ * @public
+ * {@inheritDoc PuppeteerNode.connect}
+ */
+export declare function connect(options: ConnectOptions): Promise<Browser>;
+
+/**
+ * @public
+ * {@inheritDoc Puppeteer.devices}
+ */
+export let devices: DevicesMap;
+/**
+ * @public
+ */
+export let errors: PuppeteerErrors;
+/**
+ * @public
+ */
+export let networkConditions: PredefinedNetworkConditions;
+
+/**
+ * @public
+ * {@inheritDoc Puppeteer.registerCustomQueryHandler}
+ */
+export declare function registerCustomQueryHandler(
+  name: string,
+  queryHandler: CustomQueryHandler
+): void;
+
+/**
+ * @public
+ * {@inheritDoc Puppeteer.unregisterCustomQueryHandler}
+ */
+export declare function unregisterCustomQueryHandler(name: string): void;
+/**
+ * @public
+ * {@inheritDoc Puppeteer.customQueryHandlerNames}
+ */
+export declare function customQueryHandlerNames(): string[];
+/**
+ * @public
+ * {@inheritDoc Puppeteer.clearCustomQueryHandlers}
+ */
+export declare function clearCustomQueryHandlers(): void;

src/common/NetworkConditions.ts

@@ -16,8 +16,14 @@
 
 import { NetworkConditions } from './NetworkManager.js';
 
+/**
+ * @public
+ */
 export type PredefinedNetworkConditions = { [name: string]: NetworkConditions };
 
+/**
+ * @public
+ */
 export const networkConditions: PredefinedNetworkConditions = {
   'Slow 3G': {
     download: ((500 * 1000) / 8) * 0.8,

test-ts-types/js-cjs-import-cjs-output/bad.js

@@ -0,0 +1,18 @@
+const puppeteer = require('puppeteer');
+
+async function run() {
+  // Typo in "launch"
+  const browser = await puppeteer.launh();
+  // Typo: "devices"
+  const devices = puppeteer.devics;
+  console.log(devices);
+  const browser2 = await puppeteer.launch();
+  // 'foo' is invalid argument
+  const page = await browser2.newPage('foo');
+  /**
+   * @type {puppeteer.ElementHandle<HTMLElement>}
+   */
+  const div = await page.$('div');
+  console.log('got a div!', div);
+}
+run();