15 tests covering: detect emits valid JSON when nothing configured,
reports gstack_brain_git on GSTACK_HOME/.git presence, reads
~/.gbrain/config.json engine, tolerates malformed config, detects
a mocked gbrain binary on PATH with version parsing.
For install: D5 detect-first uses ~/git/gbrain fixtures under a
sandboxed HOME, verifies fall-through to fresh clone when no valid
clone exists, rejects invalid package.json shapes. D19 PATH-shadow
validation uses a fake gbrain on a minimal SAFE_PATH to simulate
version mismatch, same-version-pass, v-prefix tolerance, missing
binary on PATH, and missing version field in package.json.
--validate-only mode in the install bin makes the D19 check unit-
testable without running real bun link (which touches ~/.bun/bin).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Garry Tan