fix(daemon): let pi exit after a session has connected to the daemon (#40)

The client's daemon socket is kept open across sessions by design; in pi -p it was the last
handle keeping Node alive, so a run that had connected to the browser hung after its answer.
Unref the socket; in-flight requests hold their own timers.

Fixes #39

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/test/daemon/fixtures/transport-exit-fixture.ts b/test/daemon/fixtures/transport-exit-fixture.ts
new file mode 100644
index 0000000..2753866
--- /dev/null
+++ b/test/daemon/fixtures/transport-exit-fixture.ts
@@ -0,0 +1,28 @@
+// Connects a daemon transport to a fake daemon that lives in this same process, with every handle
+// the fake owns unref'd. The only thing that can keep this process alive afterwards is the
+// transport's own socket, so "does the process exit on its own" is the behavior under test.
+import { createServer } from "node:net";
+import { createInterface } from "node:readline";
+import { createDaemonTransport } from "../../../src/daemon/transport";
+import { deserialize, serialize } from "../../../src/daemon/protocol";
+
+const socketPath = process.argv[2];
+if (!socketPath) throw new Error("usage: fixture <socketPath>");
+
+const server = createServer((conn) => {
+  conn.unref();
+  const rl = createInterface({ input: conn, crlfDelay: Infinity });
+  rl.on("line", (line) => {
+    const msg = deserialize(line);
+    if (msg?.type === "control" && msg.action === "register" && msg.clientId !== undefined) {
+      conn.write(serialize({ type: "control", action: "registered", clientId: msg.clientId }) + "\n");
+    }
+  });
+});
+server.unref();
+server.listen(socketPath, async () => {
+  const transport = createDaemonTransport("fixture-client", socketPath);
+  const r = await transport.connect("");
+  console.log(r.success ? "connected" : `connect failed: ${r.error.message}`);
+  // No explicit exit: if the transport socket holds the event loop, this process never ends.
+});