[clang-tools-extra] [clang-tidy] support string::contains (PR #110351)

[Nicolas van Kempen via cfe-commits]

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@@ -453,3 +490,15 @@ void testOperandPermutations(std::map<int, int>& Map) {
   // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use 'contains' to check for membership [readability-container-contains]
   // CHECK-FIXES: if (!Map.contains(0)) {};
 }
+
+void testStringNops(std::string Str, std::string SubStr) {
+  if (Str.find("test") == std::string::npos) {};
+  // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use 'contains' to check for membership [readability-container-contains]
+  // CHECK-FIXES: if (!Str.contains("test")) {};
+
+  if (Str.find('c') != std::string::npos) {};
+  // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use 'contains' to check for membership [readability-container-contains]
+  // CHECK-FIXES: if (Str.contains('c')) {};
+  
+  if (Str.find(SubStr) != std::string::npos) {};
+}
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nicovank wrote:

Add `string_view` tests, and tests comparing to `Str.npos` instead of `std::string::npos`.

https://github.com/llvm/llvm-project/pull/110351