subprocess-socket-tests

What problem does it solve?

Use this skill when tests spawn pumpkin_face.py or another TCP server in a subprocess and need deterministic readiness/cleanup across repeated runs.

Core Features & Use Cases

• Treat process-owned listening state as readiness: poll the child PID's listening ports instead of assuming "some process is listening" means the spawned server is ready.
• For command sockets that often return no payload, use a readiness teardown pattern where you ensure the server sees EOF and the client doesn't wait on a timeout.
• Centralize teardown in a helper (stop_server) so every test path terminates the spawned process the same way.
• Avoid readiness probes that consume the only pending TCP slot on a single-threaded server; if you must probe connectivity, do it after ownership is established or widen the server backlog.

Anti-Patterns

• Polling localhost:5000 until it opens without checking which PID owns the port.
• Duplicating ad hoc terminate()/wait()/kill() blocks in every test.
• Expecting no-response commands to complete quickly while keeping the write side of the socket open.

Quick Start

Run a deterministic test by spawning the server in a subprocess and verify readiness via the child process's listening ports.