[clang-tools-extra] [clang-tidy] Add avoid-pragma-once. (PR #140388)

[Tommy Chen via cfe-commits]

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@@ -0,0 +1,5 @@
+// RUN: %check_clang_tidy %s portability-avoid-pragma-once %t \
+// RUN:   -- -- -isystem %S/Inputs/avoid-pragma-once
+
+#include <lib.h>
+// CHECK-MESSAGES: :[[@LINE-1]]:1: warning: Avoid pragma once. [portability-avoid-pragma-once]
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dl8sd11 wrote:

Thanks for the pointer. I fixed the test! Feel free to take a look.

https://github.com/llvm/llvm-project/pull/140388