fix: honor OS-level PAC configuration in system proxy mode (#7766)

tests/proxy/system-pac/fixtures/collection/bruno.json

@@ -0,0 +1,6 @@
+{
+  "version": "1",
+  "name": "system-pac-proxy-test",
+  "type": "collection",
+  "ignore": []
+}

tests/proxy/system-pac/fixtures/collection/direct.bru

@@ -0,0 +1,21 @@
+meta {
+  name: direct
+  type: http
+  seq: 2
+}
+
+get {
+  url: http://localhost:19000/direct
+  body: none
+  auth: none
+}
+
+assert {
+  res.status: eq 200
+}
+
+tests {
+  test("request bypassed proxy (system PAC returned DIRECT)", function() {
+    expect(res.headers['x-proxied']).to.be.undefined;
+  });
+}

tests/proxy/system-pac/fixtures/collection/proxied.bru

@@ -0,0 +1,21 @@
+meta {
+  name: proxied
+  type: http
+  seq: 1
+}
+
+get {
+  url: http://localhost:19000/proxied
+  body: none
+  auth: none
+}
+
+assert {
+  res.status: eq 200
+}
+
+tests {
+  test("request was routed through system PAC proxy", function() {
+    expect(res.headers['x-proxied']).to.equal('test-proxy');
+  });
+}

tests/proxy/system-pac/init-user-data/preferences.json

@@ -0,0 +1,14 @@
+{
+  "maximized": false,
+  "lastOpenedCollections": ["{{projectRoot}}/tests/proxy/system-pac/fixtures/collection"],
+  "preferences": {
+    "onboarding": {
+      "hasLaunchedBefore": true,
+      "hasSeenWelcomeModal": true
+    },
+    "proxy": {
+      "source": "inherit",
+      "config": {}
+    }
+  }
+}

tests/proxy/system-pac/system-pac-proxy.spec.ts

@@ -0,0 +1,103 @@
+import * as path from 'path';
+import { execFileSync } from 'child_process';
+import { pathToFileURL } from 'url';
+import { test } from '../../../playwright';
+import { setSandboxMode, runCollection, validateRunnerResults } from '../../utils/page';
+import { startServers, stopServers, PAC_PORT, type TestServers } from '../pac/server';
+
+// GNOME's system-wide proxy schema — provided by gsettings-desktop-schemas.
+// Writes need an active dbus session (see CI workflow's dbus-run-session wrapper).
+const GNOME_PROXY_SCHEMA = 'org.gnome.system.proxy';
+
+function enableSystemPac(pacUrl: string) {
+  // Set URL first, then flip mode — otherwise auto mode briefly has no URL
+  execFileSync('gsettings', ['set', GNOME_PROXY_SCHEMA, 'autoconfig-url', pacUrl]);
+  execFileSync('gsettings', ['set', GNOME_PROXY_SCHEMA, 'mode', 'auto']);
+}
+
+function disableSystemPac() {
+  execFileSync('gsettings', ['reset', GNOME_PROXY_SCHEMA, 'mode']);
+  execFileSync('gsettings', ['reset', GNOME_PROXY_SCHEMA, 'autoconfig-url']);
+}
+
+// Detects schema availability so we can skip cleanly on minimal images
+// (e.g. containers without gsettings-desktop-schemas installed).
+function gnomeProxySchemaAvailable(): boolean {
+  try {
+    execFileSync('gsettings', ['get', GNOME_PROXY_SCHEMA, 'mode'], { stdio: 'ignore' });
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+test.describe('System Proxy with PAC', () => {
+  test.skip(
+    process.platform !== 'linux',
+    'Linux-only: relies on gsettings to set OS-level PAC'
+  );
+
+  test.skip(
+    process.platform === 'linux' && !gnomeProxySchemaAvailable(),
+    'Linux: skipping because the org.gnome.system.proxy GSettings schema is not available on this runner'
+  );
+
+  let servers: TestServers;
+
+  test.beforeAll(async () => {
+    servers = await startServers();
+  });
+
+  test.afterAll(async () => {
+    // Revert OS proxy settings even if a test failed, so the runner is left clean.
+    try {
+      disableSystemPac();
+    } finally {
+      if (servers) {
+        await stopServers(servers);
+      }
+    }
+  });
+
+  // Covers the common corporate setup: PAC hosted at an HTTP URL (e.g. WPAD).
+  test('resolves OS-level PAC URL in system proxy mode (HTTP PAC)', async ({ launchElectronApp }) => {
+    const pacUrl = `http://localhost:${PAC_PORT}/test.pac`;
+    enableSystemPac(pacUrl);
+
+    const initUserDataPath = path.join(__dirname, 'init-user-data');
+    const app = await launchElectronApp({ initUserDataPath });
+
+    const page = await app.firstWindow();
+    await page.locator('[data-app-state="loaded"]').waitFor({ timeout: 30000 });
+
+    await setSandboxMode(page, 'system-pac-proxy-test', 'developer');
+    await runCollection(page, 'system-pac-proxy-test');
+    await validateRunnerResults(page, {
+      totalRequests: 2,
+      passed: 2,
+      failed: 0,
+      skipped: 0
+    });
+  });
+
+  // Covers the local-file PAC case (user-selected .pac file on disk).
+  test('resolves OS-level PAC URL in system proxy mode (file:// PAC)', async ({ launchElectronApp }) => {
+    const pacUrl = pathToFileURL(path.join(__dirname, '..', 'pac', 'fixtures', 'pac-files', 'test.pac')).href;
+    enableSystemPac(pacUrl);
+
+    const initUserDataPath = path.join(__dirname, 'init-user-data');
+    const app = await launchElectronApp({ initUserDataPath });
+
+    const page = await app.firstWindow();
+    await page.locator('[data-app-state="loaded"]').waitFor({ timeout: 30000 });
+
+    await setSandboxMode(page, 'system-pac-proxy-test', 'developer');
+    await runCollection(page, 'system-pac-proxy-test');
+    await validateRunnerResults(page, {
+      totalRequests: 2,
+      passed: 2,
+      failed: 0,
+      skipped: 0
+    });
+  });
+});