diff --git a/scripts/ci/run_validate.sh b/scripts/ci/run_validate.sh
index f39279abe..543f1848f 100755
--- a/scripts/ci/run_validate.sh
+++ b/scripts/ci/run_validate.sh
@@ -100,7 +100,11 @@ if [ "$SCAN_MODE" = "incremental" ]; then
   EXISTING_PY_FILES=""
   for f in $CHANGED_PY_FILES; do
     if [ -f "$f" ]; then
-      EXISTING_PY_FILES="$EXISTING_PY_FILES $f"
+      if [ -z "$EXISTING_PY_FILES" ]; then
+        EXISTING_PY_FILES="$f"
+      else
+        EXISTING_PY_FILES="$EXISTING_PY_FILES $f"
+      fi
     fi
   done
   CHANGED_PY_FILES="$EXISTING_PY_FILES"
@@ -108,7 +112,7 @@ if [ "$SCAN_MODE" = "incremental" ]; then
   python3 -m compileall -q $CHANGED_PY_FILES
   python3 -m black --check --fast $CHANGED_PY_FILES
   python3 -m isort --check-only $CHANGED_PY_FILES
-  RUFF_FILES=$(echo "$CHANGED_PY_FILES" | tr ' ' '\n' | grep -v '^scripts/' | tr '\n' ' ')
+  RUFF_FILES=$(echo "$CHANGED_PY_FILES" | tr ' ' '\n' | grep -v '^scripts/' | grep -v '^$' | xargs)
   if [ -n "$RUFF_FILES" ]; then
     python3 -m ruff check $RUFF_FILES --statistics
   else