Handle no changed files correctly

bin/lint

@@ -5,4 +5,8 @@ import sys
 
 from sentry.lint.engine import check_files
 
-sys.exit(check_files(sys.argv[1:]))
+file_list = sys.argv[1:]
+if not file_list:
+    file_list = None
+
+sys.exit(check_files(file_list))

src/sentry/lint/engine.py

@@ -53,7 +53,7 @@ def check_files(file_list=None):
     ]
 
     try:
-        if not file_list:
+        if file_list is None:
             files_to_check = get_files('.')
 
         else: