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

[via llvm-commits]

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@@ -0,0 +1,27 @@
+## Test the cat command
+
+# RUN: not %{lit} -a -v %{inputs}/shtest-cat \
+# RUN: | FileCheck -match-full-lines %s
+#
+# END.
+
+# CHECK: FAIL: shtest-cat :: cat-e.txt ({{[^)]*}})
+# CHECK: cat -e {{.+}}/allchars | FileCheck {{.*}}
+# CHECK: # executed command: cat -e {{.*}}
+# CHECK: # | Unsupported: 'cat':  option -e not recognized
+# CHECK: # error: command failed with exit status: {{.*}}
+# CHECK: # executed command: FileCheck {{.*}}
+# CHECK: # error: command failed with exit status: {{.*}}
+
+# CHECK: PASS: shtest-cat :: cat-v.txt ({{[^)]*}})
+# CHECK: cat -v {{.+}}/allchars | FileCheck {{.*}}
+# CHECK: # executed command: cat -v {{.*}}
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connieyzhu wrote:

done

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