Add CLI and infra test coverage

src/cli/relay_tmux.test.ts

@@ -0,0 +1,47 @@
+import { EventEmitter } from "node:events";
+
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("node:child_process", () => {
+	const spawn = vi.fn((_cmd: string, _args: string[]) => {
+		const proc = new EventEmitter() as EventEmitter & {
+			kill: ReturnType<typeof vi.fn>;
+		};
+		queueMicrotask(() => {
+			proc.emit("exit", 0);
+		});
+		proc.kill = vi.fn();
+		return proc;
+	});
+	return { spawn };
+});
+
+const { spawnRelayTmux } = await import("./relay_tmux.js");
+const { spawn } = await import("node:child_process");
+
+describe("spawnRelayTmux", () => {
+	beforeEach(() => {
+		vi.clearAllMocks();
+	});
+
+	it("kills old session, starts new one, and attaches", async () => {
+		const session = await spawnRelayTmux("echo hi", true, true);
+		expect(session).toBe("warelay-relay");
+		const spawnMock = spawn as unknown as vi.Mock;
+		expect(spawnMock.mock.calls.length).toBe(3);
+		const calls = spawnMock.mock.calls as Array<[string, string[], unknown]>;
+		expect(calls[0][0]).toBe("tmux"); // kill-session
+		expect(calls[1][2]?.cmd ?? "").not.toBeUndefined(); // new session
+		expect(calls[2][1][0]).toBe("attach-session");
+	});
+
+	it("can skip attach", async () => {
+		await spawnRelayTmux("echo hi", false, true);
+		const spawnMock = spawn as unknown as vi.Mock;
+		const hasAttach = spawnMock.mock.calls.some(
+			(c) =>
+				Array.isArray(c[1]) && (c[1] as string[]).includes("attach-session"),
+		);
+		expect(hasAttach).toBe(false);
+	});
+});