[clang-tools-extra] Add clang-tidy check to suggest replacement of conditional statement with std::min/std::max (PR #77816)

[via cfe-commits]

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@@ -0,0 +1,34 @@
+// RUN: %check_clang_tidy %s readability-use-std-min-max %t
+
+void foo() {
+  int value1,value2,value3;
+  short value4;
+
+  // CHECK-MESSAGES: :[[@LINE+1]]:3: warning: use `std::max` instead of `<` [readability-use-std-min-max]
+  if (value1 < value2)
+    value1 = value2; // CHECK-FIXES: value1 = std::max(value1, value2);
+
+  // CHECK-MESSAGES: :[[@LINE+1]]:3: warning: use `std::min` instead of `<` [readability-use-std-min-max]
+  if (value1 < value2)
+    value2 = value1; // CHECK-FIXES: value2 = std::min(value1, value2);
+
+  // CHECK-MESSAGES: :[[@LINE+1]]:3: warning: use `std::min` instead of `>` [readability-use-std-min-max]
+  if (value2 > value1)
+    value2 = value1; // CHECK-FIXES: value2 = std::min(value2, value1);
+
+  // CHECK-MESSAGES: :[[@LINE+1]]:3: warning: use `std::max` instead of `>` [readability-use-std-min-max
+  if (value2 > value1)
+    value1 = value2; // CHECK-FIXES: value1 = std::max(value2, value1);
+
+  // No suggestion needed here
+  if (value1 == value2)
+    value1 = value2;
+  
+  // CHECK-MESSAGES: :[[@LINE+1]]:3: warning: use `std::max` instead of `<` [readability-use-std-min-max]
+  if(value1<value4)
+    value1=value4; // CHECK-FIXES: value1 = std::max(value1, value4);
+  
+  // CHECK-MESSAGES: :[[@LINE+1]]:3: warning: use `std::min` instead of `<` [readability-use-std-min-max]
+  if(value1+value2<value3)
+    value3 = value1+value2; // CHECK-FIXES: value3 = std::min(value1+value2, value3);
+}
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EugeneZelenko wrote:

What about tests that involve constants, `constexpr` , macro?

https://github.com/llvm/llvm-project/pull/77816