[llvm] [llvm-lit] Add precommit test to verify current behavior of glob expansion in lit's internal shell (PR #106325)

[Alexander Richardson via llvm-commits]

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+## Tests glob pattern expansion by listing matching files.
+# RUN: echo %{inputs}/shtest-glob/example_file*.txt
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arichardson wrote:

I'm not too familiar with the structure of the lit internal test suite - I'd say keeping the tests in separate files matches the current layout more closely. Looking at the code mkdir handles globs already so if you just run something like `not mkdir %S/example_input%.input` you can verify the error output.



https://github.com/llvm/llvm-project/pull/106325