fix-busted-cached-so

name	fix-busted-cached-so
description	busted loads _insight.so from ~/.luarocks/lib first, not build/ — must copy .so after rebuild
source	auto-skill
extracted_at	2026-06-07T01:46:20.559Z

Busted Loads Cached .so from ~/.luarocks/lib

Problem

After rebuilding the Lua binding (make insight_lua), busted tests still use the OLD .so file. Direct luajit tests work fine, but busted fails.

Root cause: busted's launcher script (~/.luarocks/bin/busted) sets package.cpath to include ~/.luarocks/lib/lua/5.1/?.so FIRST. Even with LUA_CPATH="build/bindings/lua/?.so;;", the luarocks path takes precedence because the launcher explicitly sets package.cpath.

Symptom: Direct luajit test passes, but busted test fails with old behavior.

Diagnosis

# Check which _insight.so files exist and their timestamps
ls -la bindings/lua/_insight.so build/bindings/lua/_insight.so ~/.luarocks/lib/lua/5.1/_insight.so

# Check if new code is in the .so
strings build/bindings/lua/_insight.so | grep "your_new_string"
strings ~/.luarocks/lib/lua/5.1/_insight.so | grep "your_new_string"

Fix

After rebuilding, copy the new .so to the luarocks lib directory:

# Rebuild
make -j24 insight_lua

# Copy to luarocks lib (busted loads from here first)
cp build/bindings/lua/_insight.so ~/.luarocks/lib/lua/5.1/_insight.so
cp build/backends/cpu/libinsight_cpu_backend.so ~/.luarocks/lib/lua/5.1/libinsight_cpu_backend.so

Alternative: Force LUA_CPATH

If you don't want to copy, you can try setting LUA_CPATH before the busted launcher's package.cpath assignment. But this is fragile — copying is more reliable.

Key Files

• ~/.luarocks/bin/busted — launcher script, sets package.cpath
• ~/.luarocks/lib/lua/5.1/_insight.so — cached binding
• build/bindings/lua/_insight.so — freshly built binding
• bindings/lua/_insight.so — copy target (used by LUA_CPATH="bindings/lua/?.so;;")

Prevention

Add a post-build step to CMakeLists.txt that copies the .so to the luarocks lib directory automatically.