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

[via cfe-commits]

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@@ -456,11 +461,23 @@ def extract_lines(patch_file):
     zero lines of context.  The return value is a dict mapping filename to a
     list of line `Range`s."""
     matches = {}
+
+    if whole_file:
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eoineoineoin wrote:

The script runs `git cat-file` which takes arguments as repository-root relative paths, which is why you can run it from subdirectories. In [ae17aaa](https://github.com/llvm/llvm-project/pull/204336/commits/ae17aaac4a4ebc9b665947d2c254a3b074eb4752), I've taken a slightly different tack, which avoids any line-based filtering, so avoids the need to get these line numbers. Thanks.

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