[llvm] [llvm-lit][test] Adding tests for lit's built-in cat command (PR #101530)

[Paul Kirth via llvm-commits]

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@@ -0,0 +1,12 @@
+# RUN: cat %S/txt-files/newline | FileCheck %s
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ilovepi wrote:

Maybe direct this to a file w/ `> %t`, and then you can assert some things about the output? I was thinking verifying the length and other properties, but you could probably just diff it against the original file.

https://github.com/llvm/llvm-project/pull/101530