feat(timeline): 支持拖拽调整时长与运镜/轨迹关键帧时间

src/editor/io/videoExport.test.ts

@@ -0,0 +1,46 @@
+import { beforeEach, expect, it } from "vitest";
+import { usePlaybackStore } from "../runtime/playbackStore";
+import { exportVideo } from "./videoExport";
+
+beforeEach(() => {
+  usePlaybackStore.setState({ isPlaying: false, playhead: 0, duration: 5, loop: false, editingObjectId: null });
+});
+
+/**
+ * jsdom 里既没有视口画布也没有 WebCodecs，导出会立刻失败 ——
+ * 但这里要测的正是「导出期间 / 导出之后」的播放状态收口，与导出是否成功无关。
+ */
+it("turns the playback loop off while exporting and puts it back afterwards", async () => {
+  usePlaybackStore.getState().setLoop(true);
+
+  const loopHistory: boolean[] = [];
+  const unsubscribe = usePlaybackStore.subscribe((state) => loopHistory.push(state.loop));
+
+  await expect(exportVideo("director")).rejects.toThrow();
+  unsubscribe();
+
+  // 导出一开始就关掉循环：导出永远只播一遍，不会录到回卷的一段
+  expect(loopHistory[0]).toBe(false);
+  // 导出结束后循环设置原样还回去
+  expect(usePlaybackStore.getState().loop).toBe(true);
+});
+
+it("stops playback after an export instead of resuming an endless loop", async () => {
+  // 导出前正在播放，而且开着循环 —— 这就是「播完一直循环播放」的现场
+  usePlaybackStore.getState().setLoop(true);
+  usePlaybackStore.getState().setPlaying(true);
+
+  await expect(exportVideo("director")).rejects.toThrow();
+
+  const state = usePlaybackStore.getState();
+  expect(state.isPlaying).toBe(false);
+  expect(state.loop).toBe(true);
+});
+
+it("keeps the playhead where the export found it", async () => {
+  usePlaybackStore.getState().setPlayhead(2.5);
+
+  await expect(exportVideo("director")).rejects.toThrow();
+
+  expect(usePlaybackStore.getState().playhead).toBe(2.5);
+});