From c2c2bb7e558cc0dfd2a6a7976891131f68e5a2c9 Mon Sep 17 00:00:00 2001
From: Jack Franklin <jacktfranklin@chromium.org>
Date: Mon, 19 Oct 2020 09:57:15 +0100
Subject: [PATCH] chore(agnostification): common/helper.ts (#6515)

* chore(agnostification): common/helper.ts

The `readProtocolStream` method uses `fs` only if you want to write to a
file. So we gate at the start of the function and ensure that if we got
given a path we are not in a Node environment.
---
 .travis.yml          |  2 ++
 package.json         |  2 +-
 src/common/helper.ts | 17 +++++++++++++----
 3 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 30b3fc31ce2..8fb8b9b2912 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -59,6 +59,8 @@ jobs:
 
     - node_js: "12.16.3"
       name: 'Browser tests: Linux/Chromium'
+      addons:
+        chrome: stable
       env:
         - CHROMIUM=true
       script:
diff --git a/package.json b/package.json
index 3a2a4cb3973..a0e8204581d 100644
--- a/package.json
+++ b/package.json
@@ -74,7 +74,7 @@
     "@types/ws": "^7.2.4",
     "@typescript-eslint/eslint-plugin": "^4.4.0",
     "@typescript-eslint/parser": "^4.4.0",
-    "@web/test-runner": "^0.8.4",
+    "@web/test-runner": "^0.9.2",
     "commonmark": "^0.28.1",
     "cross-env": "^7.0.2",
     "dependency-cruiser": "^9.7.0",
diff --git a/src/common/helper.ts b/src/common/helper.ts
index fd2e8190efc..dc6655d240b 100644
--- a/src/common/helper.ts
+++ b/src/common/helper.ts
@@ -15,11 +15,11 @@
  */
 import { TimeoutError } from './Errors.js';
 import { debug } from './Debug.js';
-import * as fs from 'fs';
 import { CDPSession } from './Connection.js';
 import { Protocol } from 'devtools-protocol';
 import { CommonEventEmitter } from './EventEmitter.js';
 import { assert } from './assert.js';
+import { isNode } from '../environment.js';
 
 export const debugError = debug('puppeteer:error');
 
@@ -309,9 +309,16 @@ async function readProtocolStream(
   handle: string,
   path?: string
 ): Promise<Buffer> {
+  if (!isNode && path) {
+    throw new Error('Cannot write to a path outside of Node.js environment.');
+  }
+
+  const fs = isNode ? await import('fs') : null;
+
   let eof = false;
-  let fileHandle: fs.promises.FileHandle;
-  if (path) {
+  let fileHandle: import('fs').promises.FileHandle;
+
+  if (path && fs) {
     fileHandle = await fs.promises.open(path, 'w');
   }
   const bufs = [];
@@ -323,7 +330,9 @@ async function readProtocolStream(
       response.base64Encoded ? 'base64' : undefined
     );
     bufs.push(buf);
-    if (path) await fs.promises.writeFile(fileHandle, buf);
+    if (path && fs) {
+      await fs.promises.writeFile(fileHandle, buf);
+    }
   }
   if (path) await fileHandle.close();
   await client.send('IO.close', { handle });