[ClangImporter] Add @available(*, renamed:) to imported async getters

The attribute was missing from functions with getters as their async
alternative. Only getters are imported like this, so no need to check
for the other accessors.

Resolves rdar://80612566

Author: bnbarham

lib/AST/Attr.cpp

@@ -878,7 +878,23 @@ bool DeclAttribute::printImpl(ASTPrinter &Printer, const PrintOptions &Options,
     if (!Attr->Rename.empty()) {
       Printer << ", renamed: \"" << Attr->Rename << "\"";
     } else if (Attr->RenameDecl) {
-      Printer << ", renamed: \"" << Attr->RenameDecl->getName() << "\"";
+      Printer << ", renamed: \"";
+      if (auto *Accessor = dyn_cast<AccessorDecl>(Attr->RenameDecl)) {
+        switch (Accessor->getAccessorKind()) {
+        case AccessorKind::Get:
+          Printer << "getter:";
+          break;
+        case AccessorKind::Set:
+          Printer << "setter:";
+          break;
+        default:
+          break;
+        }
+        Printer << Accessor->getStorage()->getName() << "()";
+      } else {
+        Printer << Attr->RenameDecl->getName();
+      }
+      Printer << "\"";
     }
 
     // If there's no message, but this is specifically an imported

lib/ClangImporter/ImportDecl.cpp

@@ -8087,11 +8087,18 @@ void addCompletionHandlerAttribute(Decl *asyncImport,
                                    ArrayRef<Decl *> members,
                                    ASTContext &SwiftContext) {
   auto *asyncFunc = dyn_cast_or_null<AbstractFunctionDecl>(asyncImport);
+  // Completion handler functions can be imported as getters, but the decl
+  // given back from the import is the property. Grab the underlying getter
+  if (auto *property = dyn_cast_or_null<AbstractStorageDecl>(asyncImport))
+    asyncFunc = property->getAccessor(AccessorKind::Get);
+
   if (!asyncFunc)
     return;
 
   for (auto *member : members) {
-    if (member != asyncImport) {
+    // Only add the attribute to functions that don't already have availability
+    if (member != asyncImport && isa<AbstractFunctionDecl>(member) &&
+        !member->getAttrs().hasAttribute<AvailableAttr>()) {
       member->getAttrs().add(
           AvailableAttr::createForAlternative(SwiftContext, asyncFunc));
     }

test/IDE/print_clang_objc_effectful_properties.swift

@@ -7,26 +7,32 @@
 // REQUIRES: objc_interop
 
 // CHECK-LABEL: class EffProps : NSObject {
-// CHECK:  func getDogWithCompletion(_ completionHandler: @escaping (NSObject) -> Void)
-// CHECK:  var doggo: NSObject { get async }
+// CHECK:       @available(*, renamed: "getter:doggo()")
+// CHECK-NEXT:  func getDogWithCompletion(_ completionHandler: @escaping (NSObject) -> Void)
+// CHECK:       var doggo: NSObject { get async }
 
-// CHECK:       func obtainCat(_ completionHandler: @escaping (NSObject?, Error?) -> Void)
+// CHECK:       @available(*, renamed: "getter:catto()")
+// CHECK-NEXT:  func obtainCat(_ completionHandler: @escaping (NSObject?, Error?) -> Void)
 // CHECK-NEXT:  var catto: NSObject? { get async throws }
 
-// CHECK:       func checkAvailability(completionHandler: @escaping (Bool) -> Void)
+// CHECK:       @available(*, renamed: "getter:available()")
+// CHECK-NEXT:  func checkAvailability(completionHandler: @escaping (Bool) -> Void)
 // CHECK-NEXT:  var available: Bool { get async }
 // CHECK-NEXT:  @available(swift, obsoleted: 3, renamed: "checkAvailability(completionHandler:)")
 // CHECK-NEXT:  func checkAvailabilityWithCompletionHandler(_ completionHandler: @escaping (Bool) -> Void)
 
-// CHECK:       func returnNothing(completion completionHandler: @escaping () -> Void)
+// CHECK:       @available(*, renamed: "getter:touch()")
+// CHECK-NEXT:  func returnNothing(completion completionHandler: @escaping () -> Void)
 // CHECK-NEXT:  var touch: Void { get async }
 // CHECK-NEXT:  @available(swift, obsoleted: 3, renamed: "returnNothing(completion:)")
 // CHECK-NEXT:  func returnNothingWithCompletion(_ completionHandler: @escaping () -> Void)
 
-// CHECK:       func nullableHandler(_ completion: ((String) -> Void)? = nil)
+// CHECK:       @available(*, renamed: "getter:fromNullableHandler()")
+// CHECK-NEXT:  func nullableHandler(_ completion: ((String) -> Void)? = nil)
 // CHECK-NEXT:  var fromNullableHandler: String { get async }
 
-// CHECK:  func getMainDog(_ completion: @escaping (String) -> Void)
+// CHECK:       @available(*, renamed: "getter:mainDogProp()")
+// CHECK-NEXT:  func getMainDog(_ completion: @escaping (String) -> Void)
 // CHECK-NEXT:  var mainDogProp: String { get async }
 
 // CHECK:       @available(*, renamed: "regularMainDog()")