[clang-tidy] Allow renaming macro arguments (#87792)

Although the identifier-naming.cpp lit test expected macro arguments not
to be renamed, the code seemed to already allow it. The code was simply
not being exercised because a SourceManager argument wasn't being
provided. With this change, renaming of macro arguments that expand to
renamable decls is permitted.

Author: revane

clang-tools-extra/clang-tidy/utils/RenamerClangTidyCheck.cpp

@@ -489,7 +489,7 @@ void RenamerClangTidyCheck::checkNamedDecl(const NamedDecl *Decl,
   }
 
   Failure.Info = std::move(Info);
-  addUsage(Decl, Range);
+  addUsage(Decl, Range, &SourceMgr);
 }
 
 void RenamerClangTidyCheck::check(const MatchFinder::MatchResult &Result) {

clang-tools-extra/docs/ReleaseNotes.rst

@@ -268,7 +268,7 @@ Changes in existing checks
   <clang-tidy/checks/readability/identifier-naming>` check in `GetConfigPerFile`
   mode by resolving symbolic links to header files. Fixed handling of Hungarian
   Prefix when configured to `LowerCase`. Added support for renaming designated
-  initializers.
+  initializers. Added support for renaming macro arguments.
 
 - Improved :doc:`readability-implicit-bool-conversion
   <clang-tidy/checks/readability/implicit-bool-conversion>` check to provide

clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming.cpp

@@ -108,10 +108,12 @@ USER_NS::object g_s2;
 // NO warnings or fixes expected as USER_NS and object are declared in a header file
 
 SYSTEM_MACRO(var1);
-// NO warnings or fixes expected as var1 is from macro expansion
+// CHECK-MESSAGES: :[[@LINE-1]]:14: warning: invalid case style for global variable 'var1' [readability-identifier-naming]
+// CHECK-FIXES: {{^}}SYSTEM_MACRO(g_var1);
 
 USER_MACRO(var2);
-// NO warnings or fixes expected as var2 is declared in a macro expansion
+// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: invalid case style for global variable 'var2' [readability-identifier-naming]
+// CHECK-FIXES: {{^}}USER_MACRO(g_var2);
 
 #define BLA int FOO_bar
 BLA;
@@ -602,9 +604,20 @@ static void static_Function() {
 // CHECK-FIXES: {{^}}#define MY_TEST_MACRO(X) X()
 
 void MY_TEST_Macro(function) {}
-// CHECK-FIXES: {{^}}void MY_TEST_MACRO(function) {}
-}
-}
+// CHECK-MESSAGES: :[[@LINE-1]]:20: warning: invalid case style for global function 'function' [readability-identifier-naming]
+// CHECK-FIXES: {{^}}void MY_TEST_MACRO(Function) {}
+
+#define MY_CAT_IMPL(l, r) l ## r
+#define MY_CAT(l, r) MY_CAT_IMPL(l, r)
+#define MY_MACRO2(foo) int MY_CAT(awesome_, MY_CAT(foo, __COUNTER__)) = 0
+#define MY_MACRO3(foo) int MY_CAT(awesome_, foo) = 0
+MY_MACRO2(myglob);
+MY_MACRO3(myglob);
+// No suggestions should occur even though the resulting decl of awesome_myglob#
+// or awesome_myglob are not entirely within a macro argument.
+
+} // namespace InlineNamespace
+} // namespace FOO_NS
 
 template <typename t_t> struct a {
 // CHECK-MESSAGES: :[[@LINE-1]]:32: warning: invalid case style for struct 'a'