[libcxx-commits] [libcxx] [libc++] Simplify how the global stream tests are written (PR #66842)

[Martin Storsjö via libcxx-commits]

mstorsjo wrote:

FYI, while the changed tests no longer require having an explicit `bash` available, the tests do require having an `echo` executable available (which on Windows often is provided at the same place as you get `bash`), so build configs that don't have `bash` available now try to execute them, as `UNSUPPORTED: executor-has-no-bash` was removed.

In most configs, we do have `bash` set up to be available when running tests on Windows, but I did run into one case in one setup where the tests previously were skipped but now execute and fail due to the missing `echo` executable.

(Or to make matters even more subtle - they did find some `echo` executable, but it didn't support the `-n` option, so with `echo -n 1234`, instead of echoing `1234`, it echoed `-n`. The environment where this happened, on GitHub Actions runners, just updated to a different base image a couple hours ago, where that `echo` no longer is in place any more though, so I haven't been able to figure out what `echo` executable it actually ended up using.)

https://github.com/llvm/llvm-project/pull/66842