tools/ruff.sh: Allow restricting checking to specific subtrees

tools/ruff.sh

@@ -8,13 +8,37 @@ source "$(dirname "${BASH_SOURCE[0]}")/_functions.sh"
 
 require_installed
 
+PATHS=()
+
+# Parse given command line arguments
+while [[ $# -gt 0 ]]; do
+    case $1 in
+        *) PATHS+=("$1");shift;;
+    esac
+done
+
+if [[ -n "${PATHS}" ]]; then
+    # Check whether paths exist
+    for p in "${PATHS[@]}"; do
+        if [[ -e "${p%%::*}" ]]; then
+            RUFF_ARGS+=("${p}")
+        elif [[ -n "${p}" ]]; then
+            # If the path does not exist but was non-zero, show an error
+            echo -e "${p%%::*}: No such file or directory" | print_error
+            exit 1
+        fi
+    done
+else
+	PATHS=($BASE_DIR)
+fi
+
 # Run ruff as a pre-commit hook
 run_as_precommit "ruff check" "$@"
 run_as_precommit "ruff format --check" "$@"
 
 # Run ruff
 echo "Starting code linting and formatting with ruff..." | print_info
-ruff check --fix "${BASE_DIR}" || true
-ruff format "${BASE_DIR}"
+ruff check --fix "${PATHS[@]}" || true
+ruff format "${PATHS[@]}"
 
 echo "✔ Code formatting & linting finished" | print_success