[clang] Add option to format a whole file using git-clang-format (PR #204336)

[via cfe-commits]

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@@ -190,6 +190,11 @@ def main():
         action="store_true",
         help="format lines in the stage instead of the working dir",
     )
+    p.add_argument(
+        "--whole-file",
+        action="store_true",
+        help="format whole file instead of only modified lines",
+    )
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owenca wrote:

Please move it down to right after "-v" to keep the options (mostly) sorted.

https://github.com/llvm/llvm-project/pull/204336