[clang-tools-extra] [clang-tidy] support expect no diagnosis test (PR #91293)

[Congcong Cai via cfe-commits]

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@@ -226,6 +236,10 @@ def run_clang_tidy(self):
         print("------------------------------------------------------------------")
         return clang_tidy_output
 
+    def check_no_diagnosis(self, clang_tidy_output):
+        if clang_tidy_output != "":
+            sys.exit("No diagnostics were expected, but found the ones above")
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HerrCai0907 wrote:

We don't need to print clang-tidy-output, it is already printed in https://github.com/llvm/llvm-project/pull/91293/files#diff-a05fb648cb6609a7ff1985264bfb61b73c3c226224ef0b40f3c72c9c8703daaeL213

https://github.com/llvm/llvm-project/pull/91293