feat(pi): harden subagent lifecycle

modules/agents/pi/extensions/subagents/supervisor.test.ts

@@ -0,0 +1,111 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { Supervisor } from "./supervisor.ts";
+import type { ChildHandle, ChildRunner, RunnerEvents, SpawnRequest } from "./types.ts";
+
+class FakeHandle implements ChildHandle {
+  cancelCalls = 0;
+
+  async cancel(): Promise<void> {
+    this.cancelCalls += 1;
+  }
+}
+
+class FakeRunner implements ChildRunner {
+  starts: Array<{ id: string; request: SpawnRequest; events: RunnerEvents; handle: FakeHandle }> = [];
+  autoAccept = true;
+
+  async start(id: string, request: SpawnRequest, _cwd: string, events: RunnerEvents): Promise<ChildHandle> {
+    const handle = new FakeHandle();
+    this.starts.push({ id, request, events, handle });
+    if (this.autoAccept) events.accepted(`session-${id}`);
+    return handle;
+  }
+}
+
+const sleep = (ms: number) => new Promise((resolve) => setTimeout(resolve, ms));
+
+async function spawnStarted(supervisor: Supervisor, prompt = "work") {
+  const accepted = supervisor.spawn({ prompt });
+  await sleep(0);
+  return accepted;
+}
+
+test("cancel is idempotent and reaches cancelled", async () => {
+  const runner = new FakeRunner();
+  const supervisor = new Supervisor(runner, "/tmp");
+  const accepted = await spawnStarted(supervisor);
+
+  const first = await supervisor.cancel(accepted.id);
+  const second = await supervisor.cancel(accepted.id);
+
+  assert.equal(first.state, "cancelled");
+  assert.equal(second.state, "cancelled");
+  assert.equal(runner.starts[0].handle.cancelCalls, 1);
+});
+
+test("startup timeout reaches timed_out", async () => {
+  const runner = new FakeRunner();
+  runner.autoAccept = false;
+  const supervisor = new Supervisor(runner, "/tmp", { timeouts: { startMs: 5 } });
+  const accepted = await spawnStarted(supervisor);
+
+  await sleep(20);
+
+  const status = supervisor.status(accepted.id);
+  assert.equal(status.state, "timed_out");
+  assert.equal(status.stopReason, "start_timeout");
+  assert.equal(runner.starts[0].handle.cancelCalls, 1);
+});
+
+test("runtime timeout reaches timed_out", async () => {
+  const runner = new FakeRunner();
+  const supervisor = new Supervisor(runner, "/tmp", { timeouts: { runMs: 5 } });
+  const accepted = await spawnStarted(supervisor);
+
+  await sleep(20);
+
+  const status = supervisor.status(accepted.id);
+  assert.equal(status.state, "timed_out");
+  assert.equal(status.stopReason, "run_timeout");
+  assert.equal(runner.starts[0].handle.cancelCalls, 1);
+});
+
+test("process failure reaches failed with diagnostics", async () => {
+  const runner = new FakeRunner();
+  const supervisor = new Supervisor(runner, "/tmp");
+  const accepted = await spawnStarted(supervisor);
+
+  runner.starts[0].events.failed("process closed with code 1");
+
+  const status = supervisor.status(accepted.id);
+  assert.equal(status.state, "failed");
+  assert.equal(status.error, "process closed with code 1");
+});
+
+test("shutdown cancels running children", async () => {
+  const runner = new FakeRunner();
+  const supervisor = new Supervisor(runner, "/tmp");
+  const accepted = await spawnStarted(supervisor);
+
+  await supervisor.shutdown();
+
+  const status = supervisor.status(accepted.id);
+  assert.equal(status.state, "cancelled");
+  assert.equal(status.stopReason, "shutdown");
+  assert.equal(runner.starts[0].handle.cancelCalls, 1);
+});
+
+test("completed children ignore later cancel", async () => {
+  const runner = new FakeRunner();
+  const supervisor = new Supervisor(runner, "/tmp");
+  const accepted = await spawnStarted(supervisor);
+
+  runner.starts[0].events.completed("done", "agent_settled");
+  await supervisor.cancel(accepted.id);
+
+  const result = supervisor.result(accepted.id);
+  assert.equal(result.state, "completed");
+  assert.equal(result.result, "done");
+  assert.equal(runner.starts[0].handle.cancelCalls, 0);
+});