[NFC] Merge two category name accessors

Author: beccadax

include/swift/AST/Decl.h

@@ -1912,11 +1912,6 @@ class ExtensionDecl final : public GenericContext, public Decl,
   /// \endcode
   bool isWrittenWithConstraints() const;
 
-  /// Returns the name of the category specified by the \c \@_objcImplementation
-  /// attribute, or \c None if the name is invalid or
-  /// \c isObjCImplementation() is false.
-  std::optional<Identifier> getCategoryNameForObjCImplementation() const;
-
   /// If this extension represents an imported Objective-C category, returns the
   /// category's name. Otherwise returns the empty identifier.
   Identifier getObjCCategoryName() const;

lib/AST/Decl.cpp

@@ -1891,16 +1891,6 @@ bool Decl::isObjCImplementation() const {
   return getAttrs().hasAttribute<ObjCImplementationAttr>(/*AllowInvalid=*/true);
 }
 
-std::optional<Identifier>
-ExtensionDecl::getCategoryNameForObjCImplementation() const {
-  auto attr = getAttrs()
-                  .getAttribute<ObjCImplementationAttr>(/*AllowInvalid=*/true);
-  if (!attr || attr->isCategoryNameInvalid())
-    return std::nullopt;
-
-  return attr->CategoryName;
-}
-
 PatternBindingDecl::PatternBindingDecl(SourceLoc StaticLoc,
                                        StaticSpellingKind StaticSpelling,
                                        SourceLoc VarLoc,

lib/ClangImporter/ClangImporter.cpp

@@ -5971,9 +5971,15 @@ struct OrderDecls {
 
 Identifier ExtensionDecl::getObjCCategoryName() const {
   // Could it be an imported category?
-  if (!hasClangNode())
-    // Nope, not imported.
+  if (!hasClangNode()) {
+    // Nope, not imported. Is it an @implementation extension?
+    auto attr = getAttrs()
+                    .getAttribute<ObjCImplementationAttr>(/*AllowInvalid=*/true);
+    if (attr && !attr->isCategoryNameInvalid())
+      return attr->CategoryName;
+
     return Identifier();
+  }
 
   auto category = dyn_cast<clang::ObjCCategoryDecl>(getClangDecl());
   if (!category)
@@ -6014,6 +6020,12 @@ constructResult(const llvm::TinyPtrVector<Decl *> &interfaces,
   return ObjCInterfaceAndImplementation(interfaces, impls.front());
 }
 
+static bool isCategoryNameValid(ExtensionDecl *ext) {
+  auto attr = ext->getAttrs()
+                .getAttribute<ObjCImplementationAttr>(/*AllowInvalid=*/true);
+  return attr && !attr->isCategoryNameInvalid();
+}
+
 static ObjCInterfaceAndImplementation
 findContextInterfaceAndImplementation(DeclContext *dc) {
   if (!dc)
@@ -6028,16 +6040,11 @@ findContextInterfaceAndImplementation(DeclContext *dc) {
   Identifier categoryName;
 
   if (auto ext = dyn_cast<ExtensionDecl>(dc)) {
-    if (ext->hasClangNode()) {
-      // This is either an interface, or it's not objcImpl at all.
-      categoryName = ext->getObjCCategoryName();
-    } else {
-      // This is either the implementation, or it's not objcImpl at all.
-      if (auto name = ext->getCategoryNameForObjCImplementation())
-        categoryName = *name;
-      else
-        return {};
-    }
+    assert(ext);
+    if (!ext->hasClangNode() && !isCategoryNameValid(ext))
+      return {};
+
+    categoryName = ext->getObjCCategoryName();
   } else {
     // Must be an imported class. Look for its main implementation.
     assert(isa_and_nonnull<ClassDecl>(dc));
@@ -6051,7 +6058,8 @@ findContextInterfaceAndImplementation(DeclContext *dc) {
   llvm::TinyPtrVector<Decl *> implDecls;
   for (ExtensionDecl *ext : classDecl->getExtensions()) {
     if (ext->isObjCImplementation()
-        && ext->getCategoryNameForObjCImplementation() == categoryName)
+          && ext->getObjCCategoryName() == categoryName
+          && isCategoryNameValid(ext))
       implDecls.push_back(ext);
   }
 

lib/IRGen/GenClass.cpp

@@ -1141,9 +1141,10 @@ namespace {
     std::optional<StringRef> getObjCImplCategoryName() const {
       if (!TheExtension || !TheExtension->isObjCImplementation())
         return std::nullopt;
-      if (auto ident = TheExtension->getCategoryNameForObjCImplementation()) {
-        assert(!ident->empty());
-        return ident->str();
+      assert(!TheExtension->hasClangNode());
+      auto ident = TheExtension->getObjCCategoryName();
+      if (!ident.empty()) {
+        return ident.str();
       }
       return std::nullopt;
     }

lib/IRGen/GenDecl.cpp

@@ -5860,7 +5860,7 @@ void IRGenModule::emitNestedTypeDecls(DeclRange members) {
 
 static bool shouldEmitCategory(IRGenModule &IGM, ExtensionDecl *ext) {
   if (ext->isObjCImplementation()) {
-    assert(ext->getCategoryNameForObjCImplementation() != Identifier());
+    assert(!ext->getObjCCategoryName().empty());
     return true;
   }
 
@@ -5904,8 +5904,7 @@ void IRGenModule::emitExtension(ExtensionDecl *ext) {
   if (!origClass)
     return;
 
-  if (ext->isObjCImplementation()
-        && ext->getCategoryNameForObjCImplementation() == Identifier()) {
+  if (ext->isObjCImplementation() && ext->getObjCCategoryName().empty()) {
     // This is the @_objcImplementation for the class--generate its class
     // metadata.
     emitClassDecl(origClass);

lib/Sema/TypeCheckStorage.cpp

@@ -3510,8 +3510,7 @@ static void finishStorageImplInfo(AbstractStorageDecl *storage,
 
       // @_objcImplementation extensions on a non-category can declare stored
       // properties; StoredPropertiesRequest knows to look for them there.
-      if (ext->isObjCImplementation() &&
-          ext->getCategoryNameForObjCImplementation() == Identifier())
+      if (ext->isObjCImplementation() && ext->getObjCCategoryName().empty())
         return;
 
       storage->diagnose(diag::extension_stored_property);