[clang] [clang-tools-extra] [Clang] [Diagnostics] Simplify filenames that contain '..' (PR #143520)

[via cfe-commits]

Sirraide wrote:

> The only suggestion I have might be terrible, but you could write some python to enumerate mount points, determine which ones are network drives, and then check the test path against the list of mount points.

I will say that I don’t think I know enough Python (basically none at all really) to implement this approach in a sane manner...

> Instead of operating in place, could you avoid the network mount entirely by creating the required structure under /tmp and running the test there?

We could try that (assuming that `/tmp` exists on every system but I sure hope so); it might run into issues if we somehow pick a file/directory name that something else is already using, but that’s probably not too likely.

https://github.com/llvm/llvm-project/pull/143520