[clang-tools-extra] [llvm] [clang] code-format: Improve the code-format-helper to be able to run as a git hook (PR #73957)

[Tobias Hieta via cfe-commits]

tru wrote:

This should be good now - a last look @boomanaiden154 ?

https://github.com/llvm/llvm-project/pull/73957