[llvm] [LIT] Add support for `%basename_s` to get base name of source file (PR #110993)

[Rahul Joshi via llvm-commits]

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@@ -0,0 +1,5 @@
+# Basic test for substitutions.
+#
+# RUN: echo %basename_s  | FileCheck %s --check-prefix=BASENAME
+#
+# BASENAME: substitutions.py
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jurahul wrote:

Thanks, changed it back to just CHECK. I did look at adding more checks, but some things like full path, it wasn't clear how to check that. So, restricting the test to just the new substitutions being added. if/when its extended for others, the check prefix can be updated.

https://github.com/llvm/llvm-project/pull/110993