fix: use error-like (#8504)

.gitignore

@@ -14,7 +14,7 @@ test-ts-types/**/dist/
 package-lock.json
 yarn.lock
 /node6
-/lib
+lib
 test/coverage.json
 temp/
 new-docs/

src/common/BrowserConnector.ts

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import { debugError } from '../common/helper.js';
+import { debugError, isErrorLike } from '../common/helper.js';
 import { isNode } from '../environment.js';
 import { assert } from './assert.js';
 import {
@@ -138,7 +138,7 @@ async function getWSEndpoint(browserURL: string): Promise<string> {
     const data = await result.json();
     return data.webSocketDebuggerUrl;
   } catch (error) {
-    if (error instanceof Error) {
+    if (isErrorLike(error)) {
       error.message =
         `Failed to fetch browser webSocket URL from ${endpointURL}: ` +
         error.message;

src/common/FrameManager.ts

@@ -16,7 +16,7 @@
 
 import { EventEmitter } from './EventEmitter.js';
 import { assert } from './assert.js';
-import { helper, debugError } from './helper.js';
+import { helper, debugError, isErrorLike } from './helper.js';
 import { ExecutionContext, EVALUATION_SCRIPT_URL } from './ExecutionContext.js';
 import {
   LifecycleWatcher,
@@ -163,7 +163,7 @@ export class FrameManager extends EventEmitter {
     } catch (error) {
       // The target might have been closed before the initialization finished.
       if (
-        error instanceof Error &&
+        isErrorLike(error) &&
         (error.message.includes('Target closed') ||
           error.message.includes('Session closed'))
       ) {
@@ -226,7 +226,7 @@ export class FrameManager extends EventEmitter {
           ? new Error(`${response.errorText} at ${url}`)
           : null;
       } catch (error) {
-        if (error instanceof Error) {
+        if (isErrorLike(error)) {
           return error;
         }
         throw error;

src/common/Page.ts

@@ -43,7 +43,7 @@ import {
   FrameManager,
   FrameManagerEmittedEvents,
 } from './FrameManager.js';
-import { debugError, helper } from './helper.js';
+import { debugError, helper, isErrorLike } from './helper.js';
 import { HTTPRequest } from './HTTPRequest.js';
 import { HTTPResponse } from './HTTPResponse.js';
 import { Keyboard, Mouse, MouseButton, Touchscreen } from './Input.js';
@@ -1578,7 +1578,7 @@ export class Page extends EventEmitter {
       const result = await pageBinding(...args);
       expression = helper.pageBindingDeliverResultString(name, seq, result);
     } catch (error) {
-      if (error instanceof Error)
+      if (isErrorLike(error))
         expression = helper.pageBindingDeliverErrorString(
           name,
           seq,
@@ -2360,8 +2360,9 @@ export class Page extends EventEmitter {
         timezoneId: timezoneId || '',
       });
     } catch (error) {
-      if (error instanceof Error && error.message.includes('Invalid timezone'))
+      if (isErrorLike(error) && error.message.includes('Invalid timezone')) {
         throw new Error(`Invalid timezone ID: ${timezoneId}`);
+      }
       throw error;
     }
   }

src/common/Tracing.ts

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 import { assert } from './assert.js';
-import { helper } from './helper.js';
+import { helper, isErrorLike } from './helper.js';
 import { CDPSession } from './Connection.js';
 
 /**
@@ -122,7 +122,7 @@ export class Tracing {
         const buffer = await helper.getReadableAsBuffer(readable, this._path);
         resolve(buffer ?? undefined);
       } catch (error) {
-        if (error instanceof Error) {
+        if (isErrorLike(error)) {
           reject(error);
         } else {
           reject(new Error(`Unknown error: ${error}`));

src/common/helper.ts

@@ -165,7 +165,9 @@ async function waitForEvent<T>(
       throw error;
     }
   );
-  if (result instanceof Error) throw result;
+  if (isErrorLike(result)) {
+    throw result;
+  }
 
   return result;
 }
@@ -378,6 +380,22 @@ async function getReadableFromProtocolStream(
   });
 }
 
+interface ErrorLike extends Error {
+  name: string;
+  message: string;
+}
+
+export function isErrorLike(obj: unknown): obj is ErrorLike {
+  return obj instanceof Object && 'name' in obj && 'message' in obj;
+}
+
+export function isErrnoException(obj: unknown): obj is NodeJS.ErrnoException {
+  return (
+    isErrorLike(obj) &&
+    ('errno' in obj || 'code' in obj || 'path' in obj || 'syscall' in obj)
+  );
+}
+
 export const helper = {
   evaluationString,
   pageBindingInitString,

src/node/BrowserRunner.ts

@@ -28,6 +28,8 @@ import {
   helper,
   debugError,
   PuppeteerEventListener,
+  isErrorLike,
+  isErrnoException,
 } from '../common/helper.js';
 import { LaunchOptions } from './LaunchOptions.js';
 import { Connection } from '../common/Connection.js';
@@ -216,7 +218,7 @@ export class BrowserRunner {
       } catch (error) {
         throw new Error(
           `${PROCESS_ERROR_EXPLANATION}\nError cause: ${
-            error instanceof Error ? error.stack : error
+            isErrorLike(error) ? error.stack : error
           }`
         );
       }
@@ -330,9 +332,8 @@ function pidExists(pid: number): boolean {
   try {
     return process.kill(pid, 0);
   } catch (error) {
-    if (error instanceof Error) {
+    if (isErrnoException(error)) {
-      const err = error as NodeJS.ErrnoException;
+      if (error.code && error.code === 'ESRCH') {
-      if (err.code && err.code === 'ESRCH') {
         return false;
       }
     }

test/mocha-utils.ts

@@ -14,24 +14,24 @@
  * limitations under the License.
  */
 
-import { TestServer } from '../utils/testserver/index.js';
+import Protocol from 'devtools-protocol';
-import * as path from 'path';
+import expect from 'expect';
 import * as fs from 'fs';
 import * as os from 'os';
+import * as path from 'path';
+import rimraf from 'rimraf';
 import sinon from 'sinon';
-import puppeteer from '../lib/cjs/puppeteer/puppeteer.js';
 import {
   Browser,
   BrowserContext,
 } from '../lib/cjs/puppeteer/common/Browser.js';
+import { isErrorLike } from '../lib/cjs/puppeteer/common/helper.js';
 import { Page } from '../lib/cjs/puppeteer/common/Page.js';
 import { PuppeteerNode } from '../lib/cjs/puppeteer/node/Puppeteer.js';
-import utils from './utils.js';
+import puppeteer from '../lib/cjs/puppeteer/puppeteer.js';
-import rimraf from 'rimraf';
+import { TestServer } from '../utils/testserver/index.js';
-import expect from 'expect';
-
 import { trackCoverage } from './coverage-utils.js';
-import Protocol from 'devtools-protocol';
+import utils from './utils.js';
 
 const setupServer = async () => {
   const assetsPath = path.join(__dirname, 'assets');
@@ -73,7 +73,7 @@ let extraLaunchOptions = {};
 try {
   extraLaunchOptions = JSON.parse(process.env['EXTRA_LAUNCH_OPTIONS'] || '{}');
 } catch (error) {
-  if (error instanceof Error) {
+  if (isErrorLike(error)) {
     console.warn(
       `Error parsing EXTRA_LAUNCH_OPTIONS: ${error.message}. Skipping.`
     );