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

[Paul Kirth via llvm-commits]

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@@ -0,0 +1,31 @@
+## Test the cat command
+
+# RUN: not %{lit} -a -v %{inputs}/shtest-cat \
+# RUN: | FileCheck -match-full-lines %s --dump-input-context=1000
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ilovepi wrote:

Why is `--dump-input-context=1000` needed?

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