Only check formatting on modified files (#1673)

* only check formatting on modified files (attempt 1)

* foreshadow maximum command string length being an issue and pass files list using a file

* rm temp file list otherwise it shows in git status and counts as a "formatting diff"...

* cheeky z_play modif

* format

format.py

@@ -9,6 +9,7 @@ import shutil
 import subprocess
 import sys
 import tempfile
+from pathlib import Path
 from functools import partial
 from typing import List
 
@@ -150,6 +151,15 @@ def main():
         action="store_true",
         help="Print the paths to the clang-* binaries used",
     )
+    parser.add_argument(
+        "--files-list",
+        dest="files_list",
+        help="A file listing the files to format",
+    )
+    parser.add_argument(
+        "--verbose",
+        action="store_true",
+    )
     parser.add_argument("files", metavar="file", nargs="*")
     parser.add_argument(
         "-j",
@@ -175,10 +185,18 @@ def main():
                 f"Error: neither clang-apply-replacements nor clang-apply-replacements-{CLANG_VER} found (required to use -j)"
             )
 
-    if args.files:
-        files = args.files
+    if args.files or args.files_list:
+        files = []
+        files.extend(args.files)
+        if args.files_list:
+            files.extend(Path(args.files_list).read_text().split())
+        files = list(files)
         extra_files = []
+        if args.verbose:
+            print("Formatting specific files:", len(files), files)
     else:
+        if args.verbose:
+            print("Formatting all files")
         files = glob.glob("src/**/*.c", recursive=True)
         extra_files = glob.glob("assets/**/*.xml", recursive=True)