[llvm] [lit] Implement builtin umask (PR #94621)

[Jay Foad via llvm-commits]

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@@ -0,0 +1,5 @@
+import lit.formats
+
+config.name = "shtest-umask"
+config.suffixes = [".txt"]
+config.test_format = lit.formats.ShTest(execute_external=False)
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jayfoad wrote:

Done. Can you please verify that it works? It's pretty annoying that the bots do not run `check-lit` and I have no access to a Windows box that can build LLVM.

https://github.com/llvm/llvm-project/pull/94621