Several small fixes for importing alternate names

include/swift/ClangImporter/ClangImporter.h

@@ -260,8 +260,7 @@ class ClangImporter final : public ClangModuleLoader {
   /// The return value may be an empty identifier, in which case the enum would
   /// not be imported.
   ///
-  /// This is mostly an implementation detail of the importer, but is also
-  /// used by the debugger.
+  /// This is not used by the importer itself, but is used by the debugger.
   Identifier getEnumConstantName(const clang::EnumConstantDecl *enumConstant);
 
   /// Writes the mangled name of \p clangDecl to \p os.

lib/ClangImporter/ImportDecl.cpp

@@ -2041,10 +2041,11 @@ namespace {
       decl->setImplicit();
     }
 
-    /// Create a typealias for the Swift 2 name of a Clang type declaration.
-    Decl *importSwift2TypeAlias(const clang::NamedDecl *decl,
-                                ImportedName swift2Name,
-                                ImportedName correctSwiftName);
+    /// Create a typealias for the name of a Clang type declaration in an
+    /// alternate version of Swift.
+    Decl *importCompatibilityTypeAlias(const clang::NamedDecl *decl,
+                                       ImportedName compatibilityName,
+                                       ImportedName correctSwiftName);
 
     /// Create a swift_newtype struct corresponding to a typedef. Returns
     /// nullptr if unable.
@@ -2062,7 +2063,8 @@ namespace {
       // If we've been asked to produce a Swift 2 stub, handle it via a
       // typealias.
       if (correctSwiftName)
-        return importSwift2TypeAlias(Decl, importedName, *correctSwiftName);
+        return importCompatibilityTypeAlias(Decl, importedName,
+                                            *correctSwiftName);
 
       Type SwiftType;
       if (Decl->getDeclContext()->getRedeclContext()->isTranslationUnit()) {
@@ -2277,7 +2279,8 @@ namespace {
       // If we've been asked to produce a Swift 2 stub, handle it via a
       // typealias.
       if (correctSwiftName)
-        return importSwift2TypeAlias(decl, importedName, *correctSwiftName);
+        return importCompatibilityTypeAlias(decl, importedName,
+                                            *correctSwiftName);
 
       auto dc =
           Impl.importDeclContextOf(decl, importedName.getEffectiveContext());
@@ -2693,7 +2696,8 @@ namespace {
       // If we've been asked to produce a Swift 2 stub, handle it via a
       // typealias.
       if (correctSwiftName)
-        return importSwift2TypeAlias(decl, importedName, *correctSwiftName);
+        return importCompatibilityTypeAlias(decl, importedName,
+                                            *correctSwiftName);
 
       auto dc =
           Impl.importDeclContextOf(decl, importedName.getEffectiveContext());
@@ -3957,7 +3961,8 @@ namespace {
       // If we've been asked to produce a Swift 2 stub, handle it via a
       // typealias.
       if (correctSwiftName)
-        return importSwift2TypeAlias(decl, importedName, *correctSwiftName);
+        return importCompatibilityTypeAlias(decl, importedName,
+                                            *correctSwiftName);
 
       Identifier name = importedName.getDeclName().getBaseName();
 
@@ -4092,7 +4097,8 @@ namespace {
       // If we've been asked to produce a Swift 2 stub, handle it via a
       // typealias.
       if (correctSwiftName)
-        return importSwift2TypeAlias(decl, importedName, *correctSwiftName);
+        return importCompatibilityTypeAlias(decl, importedName,
+                                            *correctSwiftName);
 
       auto name = importedName.getDeclName().getBaseName();
 
@@ -4630,9 +4636,10 @@ SwiftDeclConverter::importCFClassType(const clang::TypedefNameDecl *decl,
   return theClass;
 }
 
-Decl *SwiftDeclConverter::importSwift2TypeAlias(const clang::NamedDecl *decl,
-                                                ImportedName swift2Name,
-                                                ImportedName correctSwiftName) {
+Decl *SwiftDeclConverter::importCompatibilityTypeAlias(
+    const clang::NamedDecl *decl,
+    ImportedName compatibilityName,
+    ImportedName correctSwiftName) {
   // Import the referenced declaration. If it doesn't come in as a type,
   // we don't care.
   auto importedDecl = Impl.importDecl(decl, getActiveSwiftVersion());
@@ -4665,19 +4672,14 @@ Decl *SwiftDeclConverter::importSwift2TypeAlias(const clang::NamedDecl *decl,
 
   // Create the type alias.
   auto alias = Impl.createDeclWithClangNode<TypeAliasDecl>(
-      decl,
-      Accessibility::Public, Impl.importSourceLoc(decl->getLocStart()),
-      SourceLoc(), swift2Name.getDeclName().getBaseName(),
-      Impl.importSourceLoc(decl->getLocation()),
-      genericParams, dc);
+      decl, Accessibility::Public, Impl.importSourceLoc(decl->getLocStart()),
+      SourceLoc(), compatibilityName.getDeclName().getBaseName(),
+      Impl.importSourceLoc(decl->getLocation()), genericParams, dc);
   alias->setUnderlyingType(underlyingType);
   alias->setGenericEnvironment(genericEnv);
 
-  // Record that this is the Swift 2 version of this declaration.
-  Impl.ImportedDecls[{decl->getCanonicalDecl(), ImportNameVersion::Swift2}] =
-      alias;
-
-  // Mark it as the Swift 2 variant.
+  // Record that this is the official version of this declaration.
+  Impl.ImportedDecls[{decl->getCanonicalDecl(), getVersion()}] = alias;
   markAsVariant(alias, correctSwiftName);
   return alias;
 }
@@ -6516,7 +6518,7 @@ getSwiftNameFromClangName(StringRef replacement) {
   if (!clangDecl)
     return "";
 
-  auto importedName = importFullName(clangDecl, ImportNameVersion::Swift3);
+  auto importedName = importFullName(clangDecl, CurrentVersion);
   if (!importedName)
     return "";
 
@@ -6758,7 +6760,7 @@ ClangImporter::Implementation::importDeclImpl(const clang::NamedDecl *ClangDecl,
     Result = converter.Visit(ClangDecl);
     HadForwardDeclaration = converter.hadForwardDeclaration();
   }
-  if (!Result && version > ImportNameVersion::Swift2) {
+  if (!Result && version == CurrentVersion) {
     // If we couldn't import this Objective-C entity, determine
     // whether it was a required member of a protocol.
     bool hasMissingRequiredMember = false;
@@ -7568,7 +7570,7 @@ ClangImporter::Implementation::getSpecialTypedefKind(clang::TypedefNameDecl *dec
 
 Identifier
 ClangImporter::getEnumConstantName(const clang::EnumConstantDecl *enumConstant){
-  return Impl.importFullName(enumConstant, ImportNameVersion::Swift3)
+  return Impl.importFullName(enumConstant, Impl.CurrentVersion)
       .getDeclName()
       .getBaseName();
 }

lib/ClangImporter/ImportType.cpp

@@ -1626,7 +1626,7 @@ ParameterList *ClangImporter::Implementation::importFunctionParameterList(
     }
 
     // Figure out the name for this parameter.
-    Identifier bodyName = importFullName(param, ImportNameVersion::Swift3)
+    Identifier bodyName = importFullName(param, CurrentVersion)
                               .getDeclName()
                               .getBaseName();
 
@@ -2037,7 +2037,7 @@ Type ClangImporter::Implementation::importMethodType(
     }
 
     // Figure out the name for this parameter.
-    Identifier bodyName = importFullName(param, ImportNameVersion::Swift3)
+    Identifier bodyName = importFullName(param, CurrentVersion)
                               .getDeclName()
                               .getBaseName();
 
@@ -2194,7 +2194,7 @@ Type ClangImporter::Implementation::importAccessorMethodType(
 
   } else {
     const clang::ParmVarDecl *param = clangDecl->parameters().front();
-    ImportedName fullBodyName = importFullName(param,ImportNameVersion::Swift3);
+    ImportedName fullBodyName = importFullName(param, CurrentVersion);
     Identifier bodyName = fullBodyName.getDeclName().getBaseName();
     SourceLoc nameLoc = importSourceLoc(param->getLocation());
     Identifier argLabel = functionName.getDeclName().getArgumentNames().front();

test/APINotes/Inputs/custom-frameworks/APINotesFrameworkTest.framework/Headers/APINotesFrameworkTest.apinotes

@@ -79,7 +79,16 @@ SwiftVersions:
           - Name: accessorsOnlyRenamedRetypedClass
             PropertyKind:    Class
             SwiftImportAsAccessors: true
+    Protocols:
+      - Name: ProtoWithVersionedUnavailableMember
+        Methods:
+          - Selector: requirement
+            MethodKind: Instance
+            ResultType: 'ForwardClass * _Nullable'
     Functions:
       - Name: acceptDoublePointer
         SwiftName: 'acceptPointer(_:)'
         Nullability: [ O ]
+    Tags:
+      - Name: SomeCStruct
+        SwiftName: ImportantCStruct

test/APINotes/Inputs/custom-frameworks/APINotesFrameworkTest.framework/Headers/APINotesFrameworkTest.h

@@ -2,6 +2,8 @@ void jumpToLocation(double x, double y, double z);
 
 void acceptDoublePointer(double* _Nonnull ptr) __attribute__((swift_name("accept(_:)")));
 
+void oldAcceptDoublePointer(double* _Nonnull ptr) __attribute__((availability(swift, unavailable, replacement="acceptDoublePointer")));
+
 #ifdef __OBJC__
 
 __attribute__((objc_root_class))
@@ -13,5 +15,8 @@ __attribute__((objc_root_class))
 -(nonnull id)methodWithA:(nonnull id)a;
 @end
 
+#endif // __OBJC__
+
 #import <APINotesFrameworkTest/Properties.h>
-#endif
+#import <APINotesFrameworkTest/Protocols.h>
+#import <APINotesFrameworkTest/Types.h>

test/APINotes/Inputs/custom-frameworks/APINotesFrameworkTest.framework/Headers/Properties.h

@@ -1,3 +1,4 @@
+#ifdef __OBJC__
 #pragma clang assume_nonnull begin
 
 __attribute__((objc_root_class))
@@ -33,3 +34,4 @@ __attribute__((objc_root_class))
 @end
 
 #pragma clang assume_nonnull end
+#endif // __OBJC__

test/APINotes/Inputs/custom-frameworks/APINotesFrameworkTest.framework/Headers/Protocols.h

@@ -0,0 +1,11 @@
+#ifdef __OBJC__
+#pragma clang assume_nonnull begin
+
+@class ForwardClass; // used by API notes
+
+@protocol ProtoWithVersionedUnavailableMember
+- (nullable id)requirement;
+@end
+
+#pragma clang assume_nonnull end
+#endif // __OBJC__

test/APINotes/Inputs/custom-frameworks/APINotesFrameworkTest.framework/Headers/Types.h

@@ -0,0 +1,7 @@
+#pragma clang assume_nonnull begin
+
+struct __attribute__((swift_name("VeryImportantCStruct"))) SomeCStruct {
+	int field;
+};
+
+#pragma clang assume_nonnull end

test/APINotes/versioned-objc.swift

@@ -0,0 +1,16 @@
+// RUN: rm -rf %t && mkdir -p %t
+
+// RUN: not %target-swift-frontend -typecheck -F %S/Inputs/custom-frameworks -swift-version 4 %s 2>&1 | %FileCheck -check-prefix=CHECK-DIAGS -check-prefix=CHECK-DIAGS-4 %s
+// RUN: not %target-swift-frontend -typecheck -F %S/Inputs/custom-frameworks -swift-version 3 %s 2>&1 | %FileCheck -check-prefix=CHECK-DIAGS -check-prefix=CHECK-DIAGS-3 %s
+
+// REQUIRES: objc_interop
+
+import APINotesFrameworkTest
+
+// CHECK-DIAGS-4-NOT: versioned-objc.swift:[[@LINE-1]]:
+class ProtoWithVersionedUnavailableMemberImpl: ProtoWithVersionedUnavailableMember {
+  // CHECK-DIAGS-3: versioned-objc.swift:[[@LINE-1]]:7: error: type 'ProtoWithVersionedUnavailableMemberImpl' cannot conform to protocol 'ProtoWithVersionedUnavailableMember' because it has requirements that cannot be satisfied
+  func requirement() -> Any? { return nil }
+}
+
+let unrelatedDiagnostic: Int = nil

test/APINotes/versioned.swift

@@ -18,19 +18,41 @@ import APINotesFrameworkTest
 func testRenamedTopLevel() {
   var value = 0.0
 
-  // CHECK-DIAGS-4-NOT: versioned.swift:[[@LINE+1]]
+  // CHECK-DIAGS-4-NOT: versioned.swift:[[@LINE+1]]:
   accept(&value)
   // CHECK-DIAGS-3: versioned.swift:[[@LINE-1]]:3: error: 'accept' has been renamed to 'acceptPointer(_:)'
   // CHECK-DIAGS-3: note: 'accept' was introduced in Swift 4
 
-  // CHECK-DIAGS-4-NOT: versioned.swift:[[@LINE+1]]
+  // CHECK-DIAGS-3-NOT: versioned.swift:[[@LINE+1]]:
   acceptPointer(&value)
   // CHECK-DIAGS-4: versioned.swift:[[@LINE-1]]:3: error: 'acceptPointer' has been renamed to 'accept(_:)'
   // CHECK-DIAGS-4: note: 'acceptPointer' was obsoleted in Swift 4
 
   acceptDoublePointer(&value)
   // CHECK-DIAGS: versioned.swift:[[@LINE-1]]:3: error: 'acceptDoublePointer' has been renamed to
-  // CHECK-DIAGS-4: 'accept(_:)'
-  // CHECK-DIAGS-3: 'acceptPointer(_:)'
+  // CHECK-DIAGS-4-SAME: 'accept(_:)'
+  // CHECK-DIAGS-3-SAME: 'acceptPointer(_:)'
   // CHECK-DIAGS: note: 'acceptDoublePointer' was obsoleted in Swift 3
+
+  oldAcceptDoublePointer(&value)
+  // CHECK-DIAGS: versioned.swift:[[@LINE-1]]:3: error: 'oldAcceptDoublePointer' has been renamed to
+  // CHECK-DIAGS-4-SAME: 'accept(_:)'
+  // CHECK-DIAGS-3-SAME: 'acceptPointer(_:)'
+  // CHECK-DIAGS: note: 'oldAcceptDoublePointer' has been explicitly marked unavailable here
+
+  _ = SomeCStruct()
+  // CHECK-DIAGS: versioned.swift:[[@LINE-1]]:7: error: 'SomeCStruct' has been renamed to
+  // CHECK-DIAGS-4-SAME: 'VeryImportantCStruct'
+  // CHECK-DIAGS-3-SAME: 'ImportantCStruct'
+  // CHECK-DIAGS: note: 'SomeCStruct' was obsoleted in Swift 3
+
+  // CHECK-DIAGS-3-NOT: versioned.swift:[[@LINE+1]]:
+  _ = ImportantCStruct()
+  // CHECK-DIAGS-4: versioned.swift:[[@LINE-1]]:7: error: 'ImportantCStruct' has been renamed to 'VeryImportantCStruct'
+  // CHECK-DIAGS-4: note: 'ImportantCStruct' was obsoleted in Swift 4
+
+  // CHECK-DIAGS-4-NOT: versioned.swift:[[@LINE+1]]:
+  _ = VeryImportantCStruct()
+  // CHECK-DIAGS-3: versioned.swift:[[@LINE-1]]:7: error: 'VeryImportantCStruct' has been renamed to 'ImportantCStruct'
+  // CHECK-DIAGS-3: note: 'VeryImportantCStruct' was introduced in Swift 4
 }