Add clang-tidy configuration and watch script for improved code quality checks

tools/clang_tidy_watch.sh

@@ -0,0 +1,73 @@
+#!/usr/bin/env bash
+set -u
+
+ROOT_DIR="$(cd "$(dirname "$0")/.." && pwd)"
+cd "$ROOT_DIR" || exit 1
+
+EXTRA_ARGS=(
+  -extra-arg=-isystem
+  -extra-arg=/opt/devkitpro/devkitARM/arm-none-eabi/include/c++/15.2.0
+  -extra-arg=-isystem
+  -extra-arg=/opt/devkitpro/devkitARM/arm-none-eabi/include/c++/15.2.0/arm-none-eabi
+  -extra-arg=-isystem
+  -extra-arg=/opt/devkitpro/devkitARM/arm-none-eabi/include/c++/15.2.0/backward
+  -extra-arg=-isystem
+  -extra-arg=/opt/devkitpro/devkitARM/lib/gcc/arm-none-eabi/15.2.0/include
+  -extra-arg=-isystem
+  -extra-arg=/opt/devkitpro/devkitARM/lib/gcc/arm-none-eabi/15.2.0/include-fixed
+  -extra-arg=-isystem
+  -extra-arg=/opt/devkitpro/devkitARM/arm-none-eabi/include
+)
+
+rebuild_tidy_db() {
+  mkdir -p .clang-tidy-db
+  sed 's/-mthumb-interwork//g' compile_commands.json > .clang-tidy-db/compile_commands.json
+}
+
+collect_sources() {
+  find source include -type f \( -name '*.c' -o -name '*.cc' -o -name '*.cpp' -o -name '*.cxx' \) 2>/dev/null | sort
+}
+
+declare -A mtimes
+last_cc_mtime=""
+
+while true; do
+  if [[ ! -f compile_commands.json ]]; then
+    echo "Waiting for compile_commands.json (run CMake configure/build once)..."
+    sleep 2
+    continue
+  fi
+
+  cc_mtime="$(stat -c %Y compile_commands.json 2>/dev/null || echo 0)"
+  db_regenerated=0
+  if [[ "$cc_mtime" != "$last_cc_mtime" ]]; then
+    rebuild_tidy_db
+    last_cc_mtime="$cc_mtime"
+    db_regenerated=1
+  fi
+
+  mapfile -t files < <(collect_sources)
+  changed=()
+
+  for f in "${files[@]}"; do
+    m="$(stat -c %Y "$f" 2>/dev/null || echo 0)"
+    if [[ "${mtimes[$f]:-}" != "$m" ]]; then
+      changed+=("$f")
+      mtimes["$f"]="$m"
+    fi
+  done
+
+  if [[ $db_regenerated -eq 1 && ${#files[@]} -gt 0 ]]; then
+    changed=("${files[@]}")
+  fi
+
+  if [[ ${#changed[@]} -gt 0 ]]; then
+    echo "TIDY-WATCH-BEGIN"
+    for f in "${changed[@]}"; do
+      clang-tidy -quiet -p .clang-tidy-db "$f" "${EXTRA_ARGS[@]}" || true
+    done
+    echo "TIDY-WATCH-END"
+  fi
+
+  sleep 1
+done