1 files changed, 72 insertions, 0 deletions
diff --git a/apps/web/src/timeline/__tests__/update-pipeline.test.ts b/apps/web/src/timeline/__tests__/update-pipeline.test.ts
new file mode 100644
index 00000000..40a0e645
--- /dev/null
+++ b/apps/web/src/timeline/__tests__/update-pipeline.test.ts
@@ -0,0 +1,72 @@
+import { describe, expect, test } from "bun:test";
+import type { Transform } from "@/rendering";
+import type { SceneTracks, VideoElement } from "@/timeline";
+import { applyElementUpdate } from "@/timeline/update-pipeline";
+import { mediaTime, ZERO_MEDIA_TIME } from "@/wasm";
+
+function buildTransform(): Transform {
+	return {
+		scaleX: 1,
+		scaleY: 1,
+		position: { x: 0, y: 0 },
+		rotate: 0,
+	};
+}
+
+function buildVideoElement(overrides: Partial<VideoElement> = {}): VideoElement {
+	return {
+		id: "video-1",
+		type: "video",
+		name: "Video 1",
+		startTime: ZERO_MEDIA_TIME,
+		duration: mediaTime({ ticks: 10 }),
+		trimStart: ZERO_MEDIA_TIME,
+		trimEnd: ZERO_MEDIA_TIME,
+		mediaId: "media-1",
+		params: {
+			"transform.positionX": 0,
+			"transform.positionY": 0,
+			"transform.scaleX": 1,
+			"transform.scaleY": 1,
+			"transform.rotate": 0,
+			opacity: 1,
+		},
+		...overrides,
+	};
+}
+
+function buildTracks(element: VideoElement): SceneTracks {
+	return {
+		overlay: [],
+		main: {
+			id: "main-track",
+			type: "video",
+			name: "Main",
+			muted: false,
+			hidden: false,
+			elements: [element],
+		},
+		audio: [],
+	};
+}
+
+describe("applyElementUpdate", () => {
+	test("rounds retimed durations back to integer media time", () => {
+		const element = buildVideoElement();
+		const tracks = buildTracks(element);
+
+		const updatedElement = applyElementUpdate({
+			element,
+			patch: {
+				retime: { rate: 1.5 },
+			},
+			context: {
+				tracks,
+				trackId: tracks.main.id,
+			},
+		});
+
+		expect(updatedElement.duration).toBe(7);
+		expect(Number.isInteger(updatedElement.duration)).toBe(true);
+	});
+});