test(web): add unit tests for video-convert ffmpeg flow

Made-with: Cursor

Author: richiemcilroy

apps/web/__tests__/unit/video-convert.test.ts

@@ -0,0 +1,95 @@
+import { EventEmitter } from "node:events";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("ffmpeg-static", () => ({
+	default: "/usr/local/bin/ffmpeg",
+}));
+
+const mockReadFile = vi.fn(async (_path: string) => Buffer.from("video-data"));
+const mockUnlink = vi.fn(async (_path: string) => undefined);
+
+vi.mock("node:fs", async (importOriginal) => {
+	const actual = await importOriginal<typeof import("node:fs")>();
+	return {
+		...actual,
+		existsSync: (path: string) => path === "/usr/local/bin/ffmpeg",
+		promises: {
+			...actual.promises,
+			readFile: (path: string) => mockReadFile(path),
+			unlink: (path: string) => mockUnlink(path),
+		},
+	};
+});
+
+class MockChildProcess extends EventEmitter {
+	stderr = new EventEmitter();
+}
+
+let spawnedProcesses: MockChildProcess[] = [];
+let spawnArgs: { command: string; args: string[] }[] = [];
+
+vi.mock("node:child_process", () => ({
+	spawn: (command: string, args: string[]) => {
+		const proc = new MockChildProcess();
+		spawnedProcesses.push(proc);
+		spawnArgs.push({ command, args });
+		return proc;
+	},
+}));
+
+describe("video-convert", () => {
+	beforeEach(() => {
+		vi.clearAllMocks();
+		spawnedProcesses = [];
+		spawnArgs = [];
+	});
+
+	afterEach(() => {
+		vi.resetModules();
+	});
+
+	it("uses stream copy before transcoding", async () => {
+		const { convertRemoteVideoToMp4Buffer } = await import(
+			"@/lib/video-convert"
+		);
+
+		const resultPromise = convertRemoteVideoToMp4Buffer(
+			"https://example.com/video.m3u8",
+		);
+
+		setTimeout(() => {
+			spawnedProcesses[0]?.emit("close", 0);
+		}, 10);
+
+		const result = await resultPromise;
+
+		expect(result.toString()).toBe("video-data");
+		expect(spawnArgs).toHaveLength(1);
+		expect(spawnArgs[0]?.args).toContain("-c");
+		expect(spawnArgs[0]?.args).toContain("copy");
+	});
+
+	it("falls back to transcoding when stream copy fails", async () => {
+		const { convertRemoteVideoToMp4Buffer } = await import(
+			"@/lib/video-convert"
+		);
+
+		const resultPromise = convertRemoteVideoToMp4Buffer(
+			"https://example.com/video.m3u8",
+		);
+
+		setTimeout(() => {
+			spawnedProcesses[0]?.stderr.emit("data", Buffer.from("copy failed"));
+			spawnedProcesses[0]?.emit("close", 1);
+			setTimeout(() => {
+				spawnedProcesses[1]?.emit("close", 0);
+			}, 10);
+		}, 10);
+
+		await resultPromise;
+
+		expect(spawnArgs).toHaveLength(2);
+		expect(spawnArgs[1]?.args).toContain("libx264");
+		expect(spawnArgs[1]?.args).toContain("aac");
+	});
+});