From 148d759a4c694ffd48852f4c8c7d37d47518e46e Mon Sep 17 00:00:00 2001
From: Yury Semikhatsky <yurys@chromium.org>
Date: Tue, 21 May 2024 12:49:47 -0700
Subject: [PATCH] fix(chromium): do not fetch intercepted request body from
 network (#30938)

Fixes https://github.com/microsoft/playwright/issues/30760
---
 .../src/server/chromium/crNetworkManager.ts   |  6 +++++
 tests/page/page-request-fulfill.spec.ts       | 27 +++++++++++++++++++
 2 files changed, 33 insertions(+)

diff --git a/packages/playwright-core/src/server/chromium/crNetworkManager.ts b/packages/playwright-core/src/server/chromium/crNetworkManager.ts
index 6411457a32..3752a5c06f 100644
--- a/packages/playwright-core/src/server/chromium/crNetworkManager.ts
+++ b/packages/playwright-core/src/server/chromium/crNetworkManager.ts
@@ -376,6 +376,10 @@ export class CRNetworkManager {
       if (response.body || !expectedLength)
         return Buffer.from(response.body, response.base64Encoded ? 'base64' : 'utf8');
 
+      // Make sure no network requests sent while reading the body for fulfilled requests.
+      if (request._route?._fulfilled)
+        return Buffer.from('');
+
       // For <link prefetch we are going to receive empty body with non-empty content-length expectation. Reach out for the actual content.
       const resource = await session.send('Network.loadNetworkResource', { url: request.request.url(), frameId: this._serviceWorker ? undefined : request.request.frame()!._id, options: { disableCache: false, includeCredentials: true } });
       const chunks: Buffer[] = [];
@@ -595,6 +599,7 @@ class RouteImpl implements network.RouteDelegate {
   private readonly _session: CRSession;
   private _interceptionId: string;
   _alreadyContinuedParams: Protocol.Fetch.continueRequestParameters | undefined;
+  _fulfilled: boolean = false;
 
   constructor(session: CRSession, interceptionId: string) {
     this._session = session;
@@ -615,6 +620,7 @@ class RouteImpl implements network.RouteDelegate {
   }
 
   async fulfill(response: types.NormalizedFulfillResponse) {
+    this._fulfilled = true;
     const body = response.isBase64 ? response.body : Buffer.from(response.body).toString('base64');
 
     const responseHeaders = splitSetCookieHeader(response.headers);
diff --git a/tests/page/page-request-fulfill.spec.ts b/tests/page/page-request-fulfill.spec.ts
index 16f559b467..7b78c07625 100644
--- a/tests/page/page-request-fulfill.spec.ts
+++ b/tests/page/page-request-fulfill.spec.ts
@@ -457,3 +457,30 @@ it('should fulfill with gzip and readback', {
   await expect(page.locator('body')).toHaveCSS('background-color', 'rgb(255, 192, 203)');
   expect(await response.text()).toContain(`<div>hello, world!</div>`);
 });
+
+it('should not go to the network for fulfilled requests body', {
+  annotation: { type: 'issue', description: 'https://github.com/microsoft/playwright/issues/30760' },
+}, async ({ page, server, browserName }) => {
+  await page.route('**/one-style.css', async route => {
+    return route.fulfill({
+      status: 404,
+      contentType: 'text/plain',
+      body: 'Not Found! (mocked)',
+    });
+  });
+
+  let serverHit = false;
+  server.setRoute('/one-style.css', (req, res) => {
+    serverHit = true;
+    res.setHeader('Content-Type', 'text/css');
+    res.end('body { background-color: green; }');
+  });
+
+  const responsePromise = page.waitForResponse('**/one-style.css');
+  await page.goto(server.PREFIX + '/one-style.html');
+  const response = await responsePromise;
+  const body = await response.body();
+  expect(body).toBeTruthy();
+  expect(serverHit).toBe(false);
+});
+