8zbhzr21j: Read the video duration from videoDuration and test its m:ss format

tests/feed-view.test.ts

@@ -3,7 +3,7 @@ import { createElement } from "react";
 import { renderToStaticMarkup } from "react-dom/server";
 import { FeedView, type FeedViewProps } from "@/components/FeedView";
 import { fetchFeedPage, FeedLoadError } from "@/lib/feed-client";
-import { mergePosts, relativeTime, toCardPosts, upgradeVideos } from "@/lib/feed-model";
+import { formatDuration, mergePosts, relativeTime, toCardPost, toCardPosts, upgradeVideos } from "@/lib/feed-model";
 
 const NOW = Date.parse("2026-10-19T12:00:00Z");
 const post = (id: string, publishedAt: string, extra: Record<string, unknown> = {}) => ({
@@ -185,3 +185,21 @@ describe("video transcoding", () => {
     expect(live).toContain("<video");
   });
 });
+
+describe("video duration", () => {
+  it("reads videoDuration (seconds) first and formats it as m:ss", () => {
+    const [m] = toCardPost({ type: "post", post: { id: "v", author: {}, mediaItems: [{ mediaType: "video", videoDuration: 154, duration: 9 }] } })!.media;
+    expect(m.durationSeconds).toBe(154);
+    expect(formatDuration(154)).toBe("2:34");
+    expect(formatDuration(5)).toBe("0:05");
+    expect(formatDuration(3725)).toBe("1:02:05");
+    expect(formatDuration(0)).toBeNull();
+    expect(formatDuration(undefined)).toBeNull();
+  });
+  it("falls back to durationSeconds, then duration, else none", () => {
+    const dur = (item: object) => toCardPost({ type: "post", post: { id: "v", author: {}, mediaItems: [{ mediaType: "video", ...item }] } })!.media[0].durationSeconds;
+    expect(dur({ durationSeconds: 30 })).toBe(30);
+    expect(dur({ duration: 12 })).toBe(12);
+    expect(dur({})).toBeUndefined();
+  });
+});