Fix mpv tlang and profile parsing

src/core/services/subtitle-processing-controller.test.ts

@@ -0,0 +1,72 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { createSubtitleProcessingController } from './subtitle-processing-controller';
+import type { SubtitleData } from '../../types';
+
+function flushMicrotasks(): Promise<void> {
+  return new Promise((resolve) => setTimeout(resolve, 0));
+}
+
+test('subtitle processing emits plain subtitle immediately before tokenized payload', async () => {
+  const emitted: SubtitleData[] = [];
+  const controller = createSubtitleProcessingController({
+    tokenizeSubtitle: async (text) => ({ text, tokens: [] }),
+    emitSubtitle: (payload) => emitted.push(payload),
+  });
+
+  controller.onSubtitleChange('字幕');
+  assert.deepEqual(emitted[0], { text: '字幕', tokens: null });
+
+  await flushMicrotasks();
+  assert.deepEqual(emitted[1], { text: '字幕', tokens: [] });
+});
+
+test('subtitle processing drops stale tokenization and delivers latest subtitle only', async () => {
+  const emitted: SubtitleData[] = [];
+  let firstResolve: ((value: SubtitleData | null) => void) | undefined;
+  const controller = createSubtitleProcessingController({
+    tokenizeSubtitle: async (text) => {
+      if (text === 'first') {
+        return await new Promise<SubtitleData | null>((resolve) => {
+          firstResolve = resolve;
+        });
+      }
+      return { text, tokens: [] };
+    },
+    emitSubtitle: (payload) => emitted.push(payload),
+  });
+
+  controller.onSubtitleChange('first');
+  controller.onSubtitleChange('second');
+  assert.ok(firstResolve);
+  firstResolve({ text: 'first', tokens: [] });
+  await flushMicrotasks();
+  await flushMicrotasks();
+
+  assert.deepEqual(emitted, [
+    { text: 'first', tokens: null },
+    { text: 'second', tokens: null },
+    { text: 'second', tokens: [] },
+  ]);
+});
+
+test('subtitle processing skips duplicate plain subtitle emission', async () => {
+  const emitted: SubtitleData[] = [];
+  let tokenizeCalls = 0;
+  const controller = createSubtitleProcessingController({
+    tokenizeSubtitle: async (text) => {
+      tokenizeCalls += 1;
+      return { text, tokens: [] };
+    },
+    emitSubtitle: (payload) => emitted.push(payload),
+  });
+
+  controller.onSubtitleChange('same');
+  await flushMicrotasks();
+  controller.onSubtitleChange('same');
+  await flushMicrotasks();
+
+  const plainEmits = emitted.filter((entry) => entry.tokens === null);
+  assert.equal(plainEmits.length, 1);
+  assert.equal(tokenizeCalls, 1);
+});