refactor(youtube): extract subtitle generation pipeline

launcher/youtube/progress.test.ts

@@ -0,0 +1,55 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+
+import { runLoggedYoutubePhase } from './progress';
+
+test('runLoggedYoutubePhase logs start and finish with elapsed time', async () => {
+  const entries: Array<{ level: 'info' | 'warn'; message: string }> = [];
+  let nowMs = 1_000;
+
+  const result = await runLoggedYoutubePhase(
+    {
+      startMessage: 'Starting subtitle probe',
+      finishMessage: 'Finished subtitle probe',
+      log: (level, message) => entries.push({ level, message }),
+      now: () => nowMs,
+    },
+    async () => {
+      nowMs = 2_500;
+      return 'ok';
+    },
+  );
+
+  assert.equal(result, 'ok');
+  assert.deepEqual(entries, [
+    { level: 'info', message: 'Starting subtitle probe' },
+    { level: 'info', message: 'Finished subtitle probe (1.5s)' },
+  ]);
+});
+
+test('runLoggedYoutubePhase logs failure with elapsed time and rethrows', async () => {
+  const entries: Array<{ level: 'info' | 'warn'; message: string }> = [];
+  let nowMs = 5_000;
+
+  await assert.rejects(
+    runLoggedYoutubePhase(
+      {
+        startMessage: 'Starting whisper primary',
+        finishMessage: 'Finished whisper primary',
+        failureMessage: 'Failed whisper primary',
+        log: (level, message) => entries.push({ level, message }),
+        now: () => nowMs,
+      },
+      async () => {
+        nowMs = 8_200;
+        throw new Error('boom');
+      },
+    ),
+    /boom/,
+  );
+
+  assert.deepEqual(entries, [
+    { level: 'info', message: 'Starting whisper primary' },
+    { level: 'warn', message: 'Failed whisper primary after 3.2s: boom' },
+  ]);
+});