[clang-format] Add null-terminated path option (#123921)

clang/tools/clang-format/git-clang-format

@@ -149,6 +149,15 @@ def main():
         action="store_true",
         help="print a diff instead of applying the changes",
     )
+    p.add_argument(
+        "--diff_from_common_commit",
+        action="store_true",
+        help=(
+            "diff from the last common commit for commits in "
+            "separate branches rather than the exact point of the "
+            "commits"
+        ),
+    )
     p.add_argument(
         "--diffstat",
         action="store_true",
@@ -171,6 +180,11 @@ def main():
     p.add_argument(
         "-p", "--patch", action="store_true", help="select hunks interactively"
     )
+    p.add_argument(
+        "--print0",
+        action="store_true",
+        help="end each printed filename with a null character",
+    )
     p.add_argument(
         "-q",
         "--quiet",
@@ -196,15 +210,6 @@ def main():
         default=0,
         help="print extra information",
     )
-    p.add_argument(
-        "--diff_from_common_commit",
-        action="store_true",
-        help=(
-            "diff from the last common commit for commits in "
-            "separate branches rather than the exact point of the "
-            "commits"
-        ),
-    )
     # We gather all the remaining positional arguments into 'args' since we need
     # to use some heuristics to determine whether or not <commit> was present.
     # However, to print pretty messages, we make use of metavar and help.
@@ -260,15 +265,13 @@ def main():
                 "Ignoring the following files (wrong extension, symlink, or "
                 "ignored by clang-format):"
             )
-            for filename in ignored_files:
-                print("    %s" % filename)
+            print_filenames(ignored_files, opts.print0)
         if changed_lines:
             print("Running clang-format on the following files:")
-            for filename in changed_lines:
-                print("    %s" % filename)
+            print_filenames(changed_lines, opts.print0)
 
     if not changed_lines:
-        if opts.verbose >= 0:
+        if opts.verbose >= 0 and not opts.print0:
             print("no modified files to format")
         return 0
 
@@ -289,7 +292,7 @@ def main():
         print("new tree: %s" % new_tree)
 
     if old_tree == new_tree:
-        if opts.verbose >= 0:
+        if opts.verbose >= 0 and not opts.print0:
             print("clang-format did not modify any files")
         return 0
 
@@ -302,9 +305,9 @@ def main():
         old_tree, new_tree, force=opts.force, patch_mode=opts.patch
     )
     if (opts.verbose >= 0 and not opts.patch) or opts.verbose >= 1:
-        print("changed files:")
-        for filename in changed_files:
-            print("    %s" % filename)
+        if not opts.print0:
+            print("changed files:")
+        print_filenames(changed_files, opts.print0)
 
     return 1
 
@@ -869,5 +872,13 @@ def convert_string(bytes_input):
         return str(bytes_input)
 
 
+def print_filenames(filenames, print0):
+    for filename in filenames:
+        if print0:
+            print(filename, end="\0")
+        else:
+            print(" " * 4 + filename)
+
+
 if __name__ == "__main__":
     sys.exit(main())