AJ
e98cb7abd7
Add spawn_test() to bcc_core — spawns a stdio server for up to 3 s, captures stderr, and reports ok/exited/crashed/not_found. Key design decisions driven by real MCP server behaviour: - stdin=PIPE (never written): servers block on JSON-RPC input and stay alive, so "still running after timeout" reliably signals a healthy start. stdin=DEVNULL would send EOF, causing well-behaved servers to exit 0 and be misclassified as "exited". - Command resolved via shutil.which(augmented_path()) before Popen so subprocess PATH resolution is unambiguous across platforms. - start_new_session=True on POSIX + os.killpg on timeout: kills the whole process group, not just the launcher (npx, uvx), which would otherwise orphan the actual node/python grandchild process. - stdout=DEVNULL: draining a PIPE we don't read would deadlock at ~64 KB. - stderr drained in a daemon thread, capped at 4 KB. GUI: SpawnTester(QThread) wraps spawn_test; "Test launch" button in ServerEditor dep row (stdio only, visible when command resolves ok/warn). Result colours match the existing dep-status palette (green/amber/red). Stderr appended to the diagnostics panel if it is open. 7 new unit tests cover all outcomes and the stdin-open regression guard. Ran python bcc.py locally: button appears for stdio servers whose command resolves, is hidden for remote servers and missing-command servers. Closes #2 Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>