--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hg-web/e2e/app_e2e_test.js	Sun Aug 02 10:07:40 2026 -0700
@@ -0,0 +1,332 @@
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const os = require('node:os');
+const path = require('node:path');
+const { spawn, spawnSync } = require('node:child_process');
+const { chromium } = require('playwright-core');
+
+const BASE_URL = 'http://127.0.0.1:6970';
+const RUNFILES = process.env.JS_BINARY__RUNFILES;
+const WORKSPACE = process.env.JS_BINARY__WORKSPACE;
+
+function run(command, args, options = {}) {
+  const result = spawnSync(command, args, {
+    encoding: 'utf8',
+    ...options,
+  });
+  if (result.status !== 0) {
+    throw new Error(
+      `${command} ${args.join(' ')} failed\n${result.stdout || ''}${result.stderr || ''}`,
+    );
+  }
+  return result.stdout.trim();
+}
+
+function mercurialEnvironment(home) {
+  return {
+    ...process.env,
+    HGPLAIN: '1',
+    HGRCPATH: '',
+    HOME: home,
+  };
+}
+
+function stopProcess(child) {
+  if (!child || child.exitCode !== null) return Promise.resolve();
+  child.kill('SIGTERM');
+  return new Promise(resolve => {
+    const timer = setTimeout(() => {
+      if (child.exitCode === null) child.kill('SIGKILL');
+    }, 3000);
+    child.once('exit', () => {
+      clearTimeout(timer);
+      resolve();
+    });
+  });
+}
+
+async function waitForHttp(url, child, logs) {
+  const deadline = Date.now() + 15000;
+  while (Date.now() < deadline) {
+    if (child.exitCode !== null) {
+      throw new Error(`Server exited early with ${child.exitCode}\n${logs.join('')}`);
+    }
+    try {
+      const response = await fetch(url);
+      if (response.ok) return;
+    } catch {
+      // Keep waiting for startup.
+    }
+    await new Promise(resolve => setTimeout(resolve, 100));
+  }
+  throw new Error(`Timed out waiting for ${url}\n${logs.join('')}`);
+}
+
+function createFixtureRepository(root) {
+  const options = { env: mercurialEnvironment(root) };
+  run('hg', ['init', root], options);
+  fs.mkdirSync(path.join(root, 'docs'), { recursive: true });
+  fs.mkdirSync(path.join(root, 'src'), { recursive: true });
+  fs.writeFileSync(
+    path.join(root, 'README.md'),
+    '# Fixture Repository\n\n<script>window.__hgWebXss = true</script>\n',
+  );
+  fs.writeFileSync(path.join(root, 'docs', 'README.md'), '# Documentation\n\nNested README.\n');
+  fs.writeFileSync(path.join(root, 'src', 'main.c'), 'int main(void) { return 0; }\n');
+  run('hg', ['--repository', root, 'add'], options);
+  run('hg', ['--repository', root, 'commit', '-u', 'Test User <[email protected]>', '-m', 'Initial fixture'], options);
+  const firstNode = run('hg', ['--repository', root, 'log', '-r', '.', '-T', '{node}'], options);
+
+  fs.appendFileSync(path.join(root, 'README.md'), '\nSecond revision.\n');
+  fs.writeFileSync(path.join(root, 'new-file.txt'), 'new file\n');
+  run('hg', ['add', 'new-file.txt'], { ...options, cwd: root });
+  run('hg', ['--repository', root, 'commit', '-u', 'Test User <[email protected]>', '-m', 'Update fixture'], options);
+  const tipNode = run('hg', ['--repository', root, 'log', '-r', '.', '-T', '{node}'], options);
+  return { firstNode, tipNode };
+}
+
+async function assertJson(pathname, status = 200) {
+  const response = await fetch(`${BASE_URL}${pathname}`);
+  const body = await response.text();
+  assert.equal(response.status, status, `${pathname} status: ${body}`);
+  return JSON.parse(body);
+}
+
+async function assertPageHasNoBrowserErrors(browser, pathname, assertion) {
+  const page = await browser.newPage();
+  const errors = [];
+  page.on('pageerror', error => errors.push(`pageerror: ${error.stack || error.message}`));
+  page.on('console', message => {
+    if (message.type() === 'error') errors.push(`console: ${message.text()}`);
+  });
+  page.on('requestfailed', request => {
+    errors.push(`requestfailed: ${request.url()} ${request.failure()?.errorText || ''}`);
+  });
+  page.on('response', response => {
+    if (response.status() >= 400) {
+      errors.push(`response: ${response.status()} ${response.url()}`);
+    }
+  });
+
+  const response = await page.goto(`${BASE_URL}${pathname}`, { waitUntil: 'networkidle' });
+  assert.equal(response.status(), 200, `${pathname} document status`);
+  await assertion(page);
+  if (errors.length > 0) {
+    throw new Error(`${pathname} browser errors\n${errors.join('\n')}`);
+  }
+  await page.close();
+}
+
+async function main() {
+  assert.ok(RUNFILES, 'rules_js runfiles path is required');
+  assert.ok(WORKSPACE, 'rules_js workspace name is required');
+
+  const fixtureRoot = fs.mkdtempSync(path.join(os.tmpdir(), 'hg-web-e2e-'));
+  const appLogs = [];
+  const hgLogs = [];
+  let hgServer;
+  let appServer;
+  let browser;
+
+  try {
+    const { firstNode, tipNode } = createFixtureRepository(fixtureRoot);
+    const runfilesWorkspace = path.join(RUNFILES, WORKSPACE);
+    const serverBinary = path.join(runfilesWorkspace, 'hg-web', 'hg_web_server');
+    const chromiumPath = path.resolve(process.env.CHROMIUM_PATH);
+
+    assert.ok(fs.existsSync(serverBinary), `missing server binary: ${serverBinary}`);
+    assert.ok(fs.existsSync(chromiumPath), `missing Chromium binary: ${chromiumPath}`);
+
+    hgServer = spawn(
+      'hg',
+      [
+        '--repository', fixtureRoot,
+        'serve',
+        '--address', '127.0.0.1',
+        '--port', '4444',
+        '--accesslog', '-',
+        '--errorlog', '-',
+      ],
+      {
+        env: mercurialEnvironment(fixtureRoot),
+        stdio: ['ignore', 'pipe', 'pipe'],
+      },
+    );
+    hgServer.stdout.on('data', chunk => hgLogs.push(chunk.toString()));
+    hgServer.stderr.on('data', chunk => hgLogs.push(chunk.toString()));
+
+    appServer = spawn(serverBinary, [], {
+      cwd: runfilesWorkspace,
+      stdio: ['ignore', 'pipe', 'pipe'],
+    });
+    appServer.stdout.on('data', chunk => appLogs.push(chunk.toString()));
+    appServer.stderr.on('data', chunk => appLogs.push(chunk.toString()));
+
+    await waitForHttp(`${BASE_URL}/`, appServer, appLogs);
+    if (hgServer.exitCode !== null) {
+      throw new Error(`Mercurial server exited early with ${hgServer.exitCode}\n${hgLogs.join('')}`);
+    }
+    await waitForHttp(`${BASE_URL}/api/repo/list`, hgServer, hgLogs);
+
+    for (const pathname of ['/', '/directory', '/directory?path=docs', '/graph', `/changeset/${tipNode}`]) {
+      const response = await fetch(`${BASE_URL}${pathname}`);
+      assert.equal(response.status, 200, `${pathname} shell route`);
+      assert.match(await response.text(), /<title>Zenbu Repository<\/title>/);
+    }
+    for (const pathname of ['/page.js', '/index.css', '/base.css', '/pencil_lines.png', '/panda.png']) {
+      const response = await fetch(`${BASE_URL}${pathname}`);
+      assert.equal(response.status, 200, `${pathname} static asset`);
+      assert.ok((await response.arrayBuffer()).byteLength > 0, `${pathname} is non-empty`);
+    }
+
+    const rootList = await assertJson('/api/repo/list');
+    assert.ok(rootList.directories.some(entry => entry.basename === 'docs'));
+    assert.ok(rootList.files.some(entry => entry.basename === 'README.md'));
+
+    const nestedList = await assertJson('/api/repo/list?path=docs');
+    assert.ok(nestedList.files.some(entry => entry.basename === 'README.md'));
+
+    const fileResponse = await fetch(`${BASE_URL}/api/repo/file?path=src%2Fmain.c`);
+    assert.equal(fileResponse.status, 200);
+    assert.match(await fileResponse.text(), /int main/);
+
+    const readmeResponse = await fetch(`${BASE_URL}/api/repo/readme?path=docs`);
+    assert.equal(readmeResponse.status, 200);
+    assert.match(await readmeResponse.text(), /Nested README/);
+    assert.equal((await fetch(`${BASE_URL}/api/repo/readme?path=src`)).status, 204);
+
+    const graph = await assertJson('/api/graph/tip?style=json');
+    assert.equal(graph.node, tipNode);
+    assert.ok(graph.changesets.length >= 2);
+
+    const changeset = await assertJson(`/api/changeset/${tipNode}`);
+    assert.equal(changeset.node, tipNode);
+    assert.equal(changeset.desc, 'Update fixture');
+    assert.ok(changeset.files.some(entry => entry.file === 'new-file.txt' && entry.status === 'added'));
+    assert.ok(changeset.diff.length > 0);
+
+    for (const pathname of [
+      '/api/repo/list?path=..%2Fetc',
+      '/api/repo/file?path=..%2FREADME.md',
+      '/api/graph/not-a-node?style=json',
+      '/api/changeset/not-a-node',
+    ]) {
+      const response = await fetch(`${BASE_URL}${pathname}`);
+      assert.equal(response.status, 400, `${pathname} rejects invalid input`);
+    }
+    assert.equal((await fetch(`${BASE_URL}/missing-route`)).status, 404);
+
+    const identify = run(
+      'hg',
+      ['identify', `${BASE_URL}/repo`],
+      { env: mercurialEnvironment(fixtureRoot) },
+    );
+    assert.match(identify, new RegExp(`^${tipNode.slice(0, 12)}`));
+
+    browser = await chromium.launch({
+      executablePath: chromiumPath,
+      headless: true,
+      args: ['--no-sandbox'],
+    });
+
+    await assertPageHasNoBrowserErrors(browser, '/', async page => {
+      await page.getByRole('heading', { name: 'Zenbu Repository' }).waitFor();
+      await page.getByText('Recent Commits').waitFor();
+      await page.getByText('Repository Files').waitFor();
+      assert.equal(await page.evaluate(() => window.__hgWebXss), undefined);
+      await page.locator('.theme-toggle').click();
+    });
+
+    await assertPageHasNoBrowserErrors(browser, '/directory', async page => {
+      await page.getByText('Repository Files').waitFor();
+      await page.getByRole('link', { name: 'README.md' }).first().click();
+      await page.getByText('Fixture Repository').waitFor();
+      assert.equal(await page.evaluate(() => window.__hgWebXss), undefined);
+      await page.keyboard.press('Escape');
+
+      let delayedReadmeRequested = false;
+      let markReadmeRequested;
+      const readmeRequested = new Promise(resolve => {
+        markReadmeRequested = resolve;
+      });
+      await page.route(/\/api\/repo\/readme\?path=/, async route => {
+        delayedReadmeRequested = true;
+        markReadmeRequested();
+        await new Promise(resolve => setTimeout(resolve, 500));
+        await route.continue();
+      });
+      await page.getByRole('link', { name: 'docs' }).click();
+      await Promise.race([
+        readmeRequested,
+        new Promise((_, reject) => {
+          setTimeout(() => reject(new Error('Timed out waiting for delayed README request')), 5000);
+        }),
+      ]);
+      await page.getByRole('link', { name: 'root' }).click();
+      await page.getByText('Fixture Repository').waitFor();
+      await page.waitForTimeout(600);
+      assert.equal(await page.getByText('Documentation').count(), 0);
+      assert.equal(delayedReadmeRequested, true);
+
+      await page.getByRole('link', { name: 'src' }).click();
+      await page.getByRole('link', { name: 'main.c' }).click();
+      await page.getByText('int main(void)').waitFor();
+      await page.keyboard.press('Escape');
+    });
+
+    await assertPageHasNoBrowserErrors(browser, '/directory?path=docs', async page => {
+      await page.getByText('Documentation').waitFor();
+      await page.getByRole('link', { name: 'README.md' }).click();
+      await page.getByText('Nested README.').waitFor();
+    });
+
+    await assertPageHasNoBrowserErrors(browser, '/graph', async page => {
+      await page.getByText('Commit Graph').waitFor();
+      await page.waitForFunction(() => new URL(window.location.href).searchParams.has('tip'));
+      const graphUrl = page.url();
+      const rows = page.locator('.graph-row');
+      await rows.first().click();
+      await page.waitForURL(/\/changeset\/[0-9a-f]+$/);
+      await page.getByRole('heading', { name: 'Update fixture' }).waitFor();
+      await page.getByRole('button', { name: 'Back', exact: true }).click();
+      await page.waitForFunction(expected => window.location.href === expected, graphUrl);
+      await page.getByText('Commit Graph').waitFor();
+    });
+
+    await assertPageHasNoBrowserErrors(browser, `/changeset/${tipNode}`, async page => {
+      await page.getByRole('heading', { name: 'Update fixture' }).waitFor();
+      await page.locator('.changeset-files code').filter({ hasText: 'new-file.txt' }).waitFor();
+      await page.getByText('added', { exact: true }).waitFor();
+      await page.getByRole('region', { name: 'Changeset diff' }).waitFor();
+      await page.getByRole('button', { name: firstNode.slice(0, 12) }).click();
+      await page.waitForFunction(
+        expectedPath => window.location.pathname === expectedPath,
+        `/changeset/${firstNode}`,
+      );
+      await page.getByRole('heading', { name: 'Initial fixture' }).waitFor();
+      await page.getByRole('button', { name: 'Back', exact: true }).click();
+      await page.getByRole('heading', { name: 'Update fixture' }).waitFor();
+      await page.getByRole('button', { name: 'Back', exact: true }).click();
+      await page.getByText('Commit Graph').waitFor();
+    });
+
+    await assertPageHasNoBrowserErrors(browser, '/changeset/not-a-node', async page => {
+      await page.getByText('Recent Commits').waitFor();
+    });
+
+    await stopProcess(hgServer);
+    const unavailable = await fetch(`${BASE_URL}/api/repo/list`);
+    assert.equal(unavailable.status, 502);
+    assert.equal((await fetch(`${BASE_URL}/`)).status, 200);
+  } finally {
+    if (browser) await browser.close();
+    await stopProcess(appServer);
+    await stopProcess(hgServer);
+    fs.rmSync(fixtureRoot, { recursive: true, force: true });
+  }
+}
+
+main().catch(error => {
+  console.error(error.stack || error);
+  process.exitCode = 1;
+});