[clang-tools-extra] [clang-tidy] Fix support for typedefs in readability-identifier-naming (PR #66835)

[Piotr Zegar via cfe-commits]

https://github.com/PiotrZSL created https://github.com/llvm/llvm-project/pull/66835

Typedef rename were not properly handled when typedef were used behind pointer, or as a part of function type. Additionally because entire function were passed as an source-range, when function started with macro, such change were not marked for a fix.

Removed workaround and used proper TypedefTypeLoc instead.

Fixes #55156

>From c1c71f8b10cee9c355e5a76e3a3bcf5ac4f7d144 Mon Sep 17 00:00:00 2001
From: Piotr Zegar <me at piotrzegar.pl>
Date: Tue, 19 Sep 2023 21:22:42 +0000
Subject: [PATCH] [clang-tidy] Fix support for typedefs in
 readability-identifier-naming

Typedef rename were not properly handled when typedef were used
behind pointer, or as a part of function type. Additionally
because entire function were passed as an source-range, when
function started with macro, such change were not marked for a fix.

Removed workaround and used proper TypedefTypeLoc instead.
---
 .../utils/RenamerClangTidyCheck.cpp           | 25 ++++---------------
 clang-tools-extra/docs/ReleaseNotes.rst       |  4 ++-
 .../readability/identifier-naming.cpp         | 18 +++++++++++++
 3 files changed, 26 insertions(+), 21 deletions(-)

diff --git a/clang-tools-extra/clang-tidy/utils/RenamerClangTidyCheck.cpp b/clang-tools-extra/clang-tidy/utils/RenamerClangTidyCheck.cpp
index d24b7a65b1c4334..da1433aa2d05d47 100644
--- a/clang-tools-extra/clang-tidy/utils/RenamerClangTidyCheck.cpp
+++ b/clang-tools-extra/clang-tidy/utils/RenamerClangTidyCheck.cpp
@@ -256,26 +256,6 @@ class RenamerClangTidyVisitor
       return true;
     }
 
-    // Fix type aliases in value declarations.
-    if (const auto *Value = dyn_cast<ValueDecl>(Decl)) {
-      if (const Type *TypePtr = Value->getType().getTypePtrOrNull()) {
-        if (const auto *Typedef = TypePtr->getAs<TypedefType>())
-          Check->addUsage(Typedef->getDecl(), Value->getSourceRange(), SM);
-      }
-    }
-
-    // Fix type aliases in function declarations.
-    if (const auto *Value = dyn_cast<FunctionDecl>(Decl)) {
-      if (const auto *Typedef =
-              Value->getReturnType().getTypePtr()->getAs<TypedefType>())
-        Check->addUsage(Typedef->getDecl(), Value->getSourceRange(), SM);
-      for (const ParmVarDecl *Param : Value->parameters()) {
-        if (const TypedefType *Typedef =
-                Param->getType().getTypePtr()->getAs<TypedefType>())
-          Check->addUsage(Typedef->getDecl(), Value->getSourceRange(), SM);
-      }
-    }
-
     // Fix overridden methods
     if (const auto *Method = dyn_cast<CXXMethodDecl>(Decl)) {
       if (const CXXMethodDecl *Overridden = getOverrideMethod(Method)) {
@@ -340,6 +320,11 @@ class RenamerClangTidyVisitor
     return true;
   }
 
+  bool VisitTypedefTypeLoc(const TypedefTypeLoc &Loc) {
+    Check->addUsage(Loc.getTypedefNameDecl(), Loc.getSourceRange(), SM);
+    return true;
+  }
+
   bool VisitTagTypeLoc(const TagTypeLoc &Loc) {
     Check->addUsage(Loc.getDecl(), Loc.getSourceRange(), SM);
     return true;
diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index 6d6f51998a01e57..b8977a39239ffce 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -291,7 +291,9 @@ Changes in existing checks
   warnings when a type's forward declaration precedes its definition.
   Additionally, it now provides appropriate warnings for ``struct`` and
   ``union`` in C, while also incorporating support for the
-  ``Leading_upper_snake_case`` naming convention.
+  ``Leading_upper_snake_case`` naming convention. The handling of ``typedef``
+  has been enhanced, particularly within complex types like function pointers
+  and cases where style checks were omitted when functions started with macros.
 
 - Improved :doc:`readability-implicit-bool-conversion
   <clang-tidy/checks/readability/implicit-bool-conversion>` check to take
diff --git a/clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming.cpp b/clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming.cpp
index 3445a21bfdbc4aa..0f5fc1145f8791e 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming.cpp
+++ b/clang-tools-extra/test/clang-tidy/checkers/readability/identifier-naming.cpp
@@ -729,3 +729,21 @@ struct forward_declared_as_struct;
 class forward_declared_as_struct {
 };
 
+namespace pr55156 {
+
+typedef enum {
+  VALUE0,
+  VALUE1,
+} ValueType;
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: invalid case style for typedef 'ValueType' [readability-identifier-naming]
+// CHECK-FIXES: {{^}}} value_type_t;
+
+#define STATIC_MACRO static
+STATIC_MACRO void someFunc(ValueType a_v1, const ValueType& a_v2) {}
+// CHECK-FIXES: {{^}}STATIC_MACRO void someFunc(value_type_t a_v1, const value_type_t& a_v2) {}
+STATIC_MACRO void someFunc(const ValueType** p_a_v1, ValueType (*p_a_v2)()) {}
+// CHECK-FIXES: {{^}}STATIC_MACRO void someFunc(const value_type_t** p_a_v1, value_type_t (*p_a_v2)()) {}
+STATIC_MACRO ValueType someFunc() {}
+// CHECK-FIXES: {{^}}STATIC_MACRO value_type_t someFunc() {}
+#undef STATIC_MACRO
+}