[clang] Add "clang-format-on-save-mode" minor mode to clang-format.el (PR #104533)

[Campbell Barton via cfe-commits]

ideasman42 wrote:

> I'm not an emacs user and I'm unsure if the other maintainers are. If you are happy to address any issues that might arise I'd be happy for this to land.

Yes, I'm happy to resolve any issues - for some context, I've been using a version of this for some years.
Originally from this answer https://emacs.stackexchange.com/q/48500/2418

The minor mode just makes it convenient to enable/disable - I find it especially when working on some projects that don't use clang-format to optionally check for `.clang-format` and only format-on-save in this case (that behavior can be configured too).


https://github.com/llvm/llvm-project/pull/104533