fix: pick the highest Chromium version in a milestone, not the most recent release

src/utils/get-chromium-tags.ts

@@ -1,3 +1,5 @@
+import { compareChromiumVersions } from './compare-chromium-versions.js';
+
 type ReleaseType = 'Extended' | 'Stable' | 'Beta' | 'Dev' | 'Canary';
 
 export type ReleaseParams = {
@@ -30,5 +32,10 @@ export async function getChromiumReleases({
     throw new Error(`Failed to fetch Chromium releases: ${response.status}`);
   }
   const releases = (await response.json()) as Release[];
-  return releases.sort((a, b) => a.time - b.time).map((r) => r.version);
+  // Order by version rather than release time: channels (Extended, Stable,
+  // Beta, ...) and platforms within a milestone ship on their own schedules,
+  // so the most recently released entry is not necessarily the newest version.
+  return releases
+    .sort((a, b) => compareChromiumVersions(a.version, b.version))
+    .map((r) => r.version);
 }

tests/utils/get-chromium-tags.spec.ts

@@ -0,0 +1,92 @@
+import nock from 'nock';
+import { afterEach, describe, expect, it } from 'vitest';
+
+import { getChromiumReleases, Release } from '../../src/utils/get-chromium-tags.js';
+
+describe('getChromiumReleases', () => {
+  afterEach(() => {
+    nock.cleanAll();
+  });
+
+  function mockReleases(releases: Partial<Release>[]) {
+    return nock('https://chromiumdash.appspot.com')
+      .get('/fetch_releases')
+      .query(true)
+      .reply(200, releases);
+  }
+
+  it('orders releases by version rather than by release time', async () => {
+    // An Extended release can go out after a Stable or Beta release in the
+    // same milestone while still carrying an older version.
+    mockReleases([
+      {
+        channel: 'Extended',
+        platform: 'Windows',
+        milestone: 156,
+        time: 4000,
+        version: '156.0.8078.13',
+      },
+      {
+        channel: 'Stable',
+        platform: 'Windows',
+        milestone: 156,
+        time: 3000,
+        version: '156.0.8078.12',
+      },
+      {
+        channel: 'Beta',
+        platform: 'Windows',
+        milestone: 156,
+        time: 2000,
+        version: '156.0.8078.17',
+      },
+      { channel: 'Beta', platform: 'Mac', milestone: 156, time: 1000, version: '156.0.8078.4' },
+    ]);
+
+    const releases = await getChromiumReleases({ milestone: 156 });
+
+    expect(releases).toEqual(['156.0.8078.4', '156.0.8078.12', '156.0.8078.13', '156.0.8078.17']);
+    expect(releases[releases.length - 1]).toEqual('156.0.8078.17');
+  });
+
+  it('compares version components numerically', async () => {
+    mockReleases([
+      { channel: 'Stable', platform: 'Linux', milestone: 156, time: 2000, version: '156.0.8078.9' },
+      {
+        channel: 'Stable',
+        platform: 'Linux',
+        milestone: 156,
+        time: 1000,
+        version: '156.0.8078.10',
+      },
+    ]);
+
+    await expect(getChromiumReleases({ milestone: 156 })).resolves.toEqual([
+      '156.0.8078.9',
+      '156.0.8078.10',
+    ]);
+  });
+
+  it('passes the channel and milestone filters to chromiumdash', async () => {
+    const scope = nock('https://chromiumdash.appspot.com')
+      .get('/fetch_releases')
+      .query({
+        platform: 'Win32,Windows,Linux,Mac',
+        num: '10',
+        channel: 'Canary',
+        milestone: '157',
+      })
+      .reply(200, []);
+
+    await expect(getChromiumReleases({ channel: 'Canary', milestone: 157 })).resolves.toEqual([]);
+    expect(scope.isDone()).toBe(true);
+  });
+
+  it('throws when chromiumdash responds with an error', async () => {
+    nock('https://chromiumdash.appspot.com').get('/fetch_releases').query(true).reply(500);
+
+    await expect(getChromiumReleases({ milestone: 156 })).rejects.toThrow(
+      'Failed to fetch Chromium releases: 500',
+    );
+  });
+});