[cxx-interop] Allow anonymous enums to be imported as non-constants.

lib/ClangImporter/ClangAdapter.cpp

@@ -711,7 +711,8 @@ bool importer::isObjCId(const clang::Decl *decl) {
 }
 
 bool importer::isUnavailableInSwift(
-    const clang::Decl *decl, const PlatformAvailability &platformAvailability,
+    const clang::Decl *decl,
+    const PlatformAvailability *platformAvailability,
     bool enableObjCInterop) {
   // 'id' is always unavailable in Swift.
   if (enableObjCInterop && isObjCId(decl))
@@ -724,7 +725,10 @@ bool importer::isUnavailableInSwift(
     if (attr->getPlatform()->getName() == "swift")
       return true;
 
-    if (!platformAvailability.isPlatformRelevant(
+    if (!platformAvailability)
+      continue;
+
+    if (!platformAvailability->isPlatformRelevant(
             attr->getPlatform()->getName())) {
       continue;
     }
@@ -733,7 +737,7 @@ bool importer::isUnavailableInSwift(
     llvm::VersionTuple version = attr->getDeprecated();
     if (version.empty())
       continue;
-    if (platformAvailability.treatDeprecatedAsUnavailable(
+    if (platformAvailability->treatDeprecatedAsUnavailable(
             decl, version, /*isAsync=*/false)) {
       return true;
     }

lib/ClangImporter/ClangAdapter.h

@@ -160,7 +160,7 @@ bool isObjCId(const clang::Decl *decl);
 
 /// Determine whether the given declaration is considered
 /// 'unavailable' in Swift.
-bool isUnavailableInSwift(const clang::Decl *decl, const PlatformAvailability &,
+bool isUnavailableInSwift(const clang::Decl *decl, const PlatformAvailability *,
                           bool enableObjCInterop);
 
 /// Determine the optionality of the given Clang parameter.

lib/ClangImporter/ImportEnumInfo.cpp

@@ -69,8 +69,16 @@ void EnumInfo::classifyEnum(const clang::EnumDecl *decl,
   // underlying type of the enum, because there is no way to conjure up a
   // name for the Swift type.
   if (!decl->hasNameForLinkage()) {
-    kind = EnumKind::Constants;
-    return;
+    // If this enum comes from a typedef, we can find a name.
+    if (!isa<clang::TypedefType>(decl->getIntegerType().getTypePtr()) ||
+        // If the typedef is available in Swift, the user will get ambiguity.
+        // It also means they may not have intended this API to be imported like this.
+        !importer::isUnavailableInSwift(
+            cast<clang::TypedefType>(decl->getIntegerType().getTypePtr())->getDecl(),
+            nullptr, true)) {
+      kind = EnumKind::Constants;
+      return;
+    }
   }
 
   // First, check for attributes that denote the classification.
@@ -339,7 +347,16 @@ void EnumInfo::determineConstantNamePrefix(const clang::EnumDecl *decl) {
 
     // Don't use importFullName() here, we want to ignore the swift_name
     // and swift_private attributes.
-    StringRef enumNameStr = decl->getName();
+    StringRef enumNameStr;
+    // If there's no name, this must be typedef. So use the typedef's name.
+    if (!decl->hasNameForLinkage()) {
+      auto typedefDecl = cast<clang::TypedefType>(
+                             decl->getIntegerType().getTypePtr())->getDecl();
+      enumNameStr = typedefDecl->getName();
+    } else {
+      enumNameStr = decl->getName();
+    }
+
     if (enumNameStr.empty())
       enumNameStr = decl->getTypedefNameForAnonDecl()->getName();
     assert(!enumNameStr.empty() && "should have been classified as Constants");

lib/ClangImporter/ImportName.cpp

@@ -1417,7 +1417,7 @@ bool NameImporter::hasErrorMethodNameCollision(
   // been marked NS_SWIFT_UNAVAILABLE, because it's actually marked unavailable,
   // or because it was deprecated before our API sunset. We can handle
   // "conflicts" where one form is unavailable.
-  return !isUnavailableInSwift(conflict, availability,
+  return !isUnavailableInSwift(conflict, &availability,
                                enableObjCInterop());
 }
 
@@ -1742,6 +1742,21 @@ ImportedName NameImporter::importNameImpl(const clang::NamedDecl *D,
       }
     }
 
+    // If this enum inherits from a typedef we can compute the name from the
+    // typedef (even if it's an anonymous enum).
+    if (auto enumDecl = dyn_cast<clang::EnumDecl>(D)) {
+      // Intentionally don't get the cannonical type here.
+      if (auto typedefType = dyn_cast<clang::TypedefType>(enumDecl->getIntegerType().getTypePtr())) {
+        // If the typedef is available in Swift, the user will get ambiguity.
+        // It also means they may not have intended this API to be imported like this.
+        if (importer::isUnavailableInSwift(typedefType->getDecl(), nullptr, true)) {
+          result.setDeclName(swiftCtx.getIdentifier(typedefType->getDecl()->getName()));
+          result.setEffectiveContext(D->getDeclContext());
+          return result;
+        }
+      }
+    }
+
     // Otherwise, for empty names, there is nothing to do.
     return result;
   }

lib/ClangImporter/ImporterImpl.h

@@ -1148,7 +1148,7 @@ class LLVM_LIBRARY_VISIBILITY ClangImporter::Implementation
   /// 'unavailable' in Swift.
   bool isUnavailableInSwift(const clang::Decl *decl) {
     return importer::isUnavailableInSwift(
-        decl, platformAvailability, SwiftContext.LangOpts.EnableObjCInterop);
+        decl, &platformAvailability, SwiftContext.LangOpts.EnableObjCInterop);
   }
 
   /// Add "Unavailable" annotation to the swift declaration.

test/Interop/Cxx/enum/Inputs/anonymous-with-swift-name.h

@@ -0,0 +1,22 @@
+#ifndef TEST_INTEROP_CXX_ENUM_INPUTS_ANONYMOUS_WITH_SWIFT_NAME_H
+#define TEST_INTEROP_CXX_ENUM_INPUTS_ANONYMOUS_WITH_SWIFT_NAME_H
+
+#define SOME_OPTIONS(_type, _name) __attribute__((availability(swift, unavailable))) _type _name; enum __attribute__((flag_enum,enum_extensibility(open))) : _name
+#define CF_OPTIONS(_type, _name) __attribute__((availability(swift, unavailable))) _type _name; enum : _name
+
+typedef SOME_OPTIONS(unsigned, SOColorMask) {
+    kSOColorMaskRed = (1 << 1),
+    kSOColorMaskGreen = (1 << 2),
+    kSOColorMaskBlue = (1 << 3),
+    kSOColorMaskAll = ~0U
+};
+
+
+typedef CF_OPTIONS(unsigned, CFColorMask) {
+  kCFColorMaskRed = (1 << 1),
+  kCFColorMaskGreen = (1 << 2),
+  kCFColorMaskBlue = (1 << 3),
+  kCFColorMaskAll = ~0U
+};
+
+#endif // TEST_INTEROP_CXX_ENUM_INPUTS_ANONYMOUS_WITH_SWIFT_NAME_H

test/Interop/Cxx/enum/Inputs/module.modulemap

@@ -7,3 +7,8 @@ module ScopedEnums {
   header "scoped-enums.h"
   requires cplusplus
 }
+
+module AnonymousWithSwiftName {
+  header "anonymous-with-swift-name.h"
+  requires cplusplus
+}

test/Interop/Cxx/enum/anonymous-with-swift-name-module-interface.swift

@@ -0,0 +1,55 @@
+// RUN: %target-swift-ide-test -print-module -module-to-print=AnonymousWithSwiftName -I %S/Inputs -source-filename=x -enable-experimental-cxx-interop | %FileCheck %s
+
+// CHECK: @available(*, unavailable, message: "Not available in Swift")
+// CHECK: typealias SOColorMask = UInt32
+
+// CHECK: struct SOColorMask : OptionSet, @unchecked Sendable {
+// CHECK:   init(rawValue: UInt32)
+// CHECK:   let rawValue: UInt32
+// CHECK:   typealias RawValue = UInt32
+// CHECK:   typealias Element = SOColorMask
+// CHECK:   typealias ArrayLiteralElement = SOColorMask
+
+// CHECK:   static var red: SOColorMask { get }
+// CHECK:   @available(swift, obsoleted: 3, renamed: "red")
+// CHECK:   static var Red: SOColorMask { get }
+
+// CHECK:   static var green: SOColorMask { get }
+// CHECK:   @available(swift, obsoleted: 3, renamed: "green")
+// CHECK:   static var Green: SOColorMask { get }
+
+// CHECK:   static var blue: SOColorMask { get }
+// CHECK:   @available(swift, obsoleted: 3, renamed: "blue")
+// CHECK:   static var Blue: SOColorMask { get }
+
+// CHECK:   static var all: SOColorMask { get }
+// CHECK:   @available(swift, obsoleted: 3, renamed: "all")
+// CHECK:   static var All: SOColorMask { get }
+// CHECK: }
+
+// CHECK: @available(*, unavailable, message: "Not available in Swift")
+// CHECK: typealias CFColorMask = UInt32
+
+// CHECK: struct CFColorMask : OptionSet {
+// CHECK:   init(rawValue: UInt32)
+// CHECK:   let rawValue: UInt32
+// CHECK:   typealias RawValue = UInt32
+// CHECK:   typealias Element = CFColorMask
+// CHECK:   typealias ArrayLiteralElement = CFColorMask
+
+// CHECK:   static var red: CFColorMask { get }
+// CHECK:   @available(swift, obsoleted: 3, renamed: "red")
+// CHECK:   static var Red: CFColorMask { get }
+
+// CHECK:   static var green: CFColorMask { get }
+// CHECK:   @available(swift, obsoleted: 3, renamed: "green")
+// CHECK:   static var Green: CFColorMask { get }
+
+// CHECK:   static var blue: CFColorMask { get }
+// CHECK:   @available(swift, obsoleted: 3, renamed: "blue")
+// CHECK:   static var Blue: CFColorMask { get }
+
+// CHECK:   static var all: CFColorMask { get }
+// CHECK:   @available(swift, obsoleted: 3, renamed: "all")
+// CHECK:   static var All: CFColorMask { get }
+// CHECK: }

test/Interop/Cxx/enum/anonymous-with-swift-name.swift

@@ -0,0 +1,34 @@
+// RUN: %target-run-simple-swift(-I %S/Inputs -Xfrontend -enable-experimental-cxx-interop)
+
+// REQUIRES: executable_test
+
+import AnonymousWithSwiftName
+import StdlibUnittest
+
+var AnonymousEnumsTestSuite = TestSuite("Anonymous Enums With Swift Name")
+
+AnonymousEnumsTestSuite.test("SOME_OPTIONS") {
+  let red: SOColorMask = .red
+  let green = SOColorMask.green
+  let blue = .blue as SOColorMask
+  let all: SOColorMask = .all
+
+  expectEqual(red.rawValue, 2)
+  expectEqual(green.rawValue, 4)
+  expectEqual(blue.rawValue, 8)
+   expectEqual(all.rawValue, ~CUnsignedInt(0))
+}
+
+AnonymousEnumsTestSuite.test("CF_OPTIONS") {
+  let red: SOColorMask = .red
+  let green = SOColorMask.green
+  let blue = .blue as SOColorMask
+  let all: SOColorMask = .all
+
+  expectEqual(red.rawValue, 2)
+  expectEqual(green.rawValue, 4)
+  expectEqual(blue.rawValue, 8)
+  expectEqual(all.rawValue, ~CUnsignedInt(0))
+}
+
+runAllTests()