[clang-tools-extra] [clang-tidy] Add bugprone-macro-condition check (PR #210768)

[Richard Thomson via cfe-commits]

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@@ -0,0 +1,87 @@
+// RUN: %check_clang_tidy %s bugprone-macro-condition %t
+
+#define USE_FOO 0
+// CHECK-MESSAGES: :[[@LINE-1]]:9: warning: Macro 'USE_FOO' defined here with a value and checked for definition
+
+#if defined(USE_FOO)
+// CHECK-MESSAGES: :[[@LINE-1]]:5: warning: Macro 'USE_FOO' defined with a value and checked here for definition
+void f()
+{
+  extern void foo();
+  foo();
+}
+#endif
+
+#if 0
+#elif OTHER_MACRO
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: Undefined macro 'OTHER_MACRO' checked here for value
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LegalizeAdulthood wrote:

I've added `-U` and `-D` test cases.

https://github.com/llvm/llvm-project/pull/210768