Sema: Exportability check enums and classes in non-library-evolution mode

include/swift/AST/DeclAttr.def

@@ -474,7 +474,7 @@ SIMPLE_DECL_ATTR(_alwaysEmitIntoClient, AlwaysEmitIntoClient,
   83)
 
 SIMPLE_DECL_ATTR(_implementationOnly, ImplementationOnly,
-  OnImport | OnFunc | OnConstructor | OnVar | OnSubscript | OnStruct,
+  OnImport | OnFunc | OnConstructor | OnVar | OnSubscript | OnStruct | OnClass | OnEnum,
   UserInaccessible | ABIStableToAdd | ABIStableToRemove | APIStableToAdd | APIStableToRemove | UnreachableInABIAttr,
   84)
 

include/swift/AST/DiagnosticsSema.def

@@ -3848,7 +3848,7 @@ ERROR(decl_from_hidden_module,none,
       "C++ types from imported module %2 do not support library evolution|"
       "it was imported via the internal bridging header|"
       "%2 was not imported publicly|"
-      "it is a struct marked '@_implementationOnly'}3",
+      "%0 is marked '@_implementationOnly'}3",
       (const Decl *, unsigned, Identifier, unsigned))
 ERROR(typealias_desugars_to_type_from_hidden_module,none,
       "%0 aliases '%1.%2' and cannot be used %select{here|"
@@ -3867,7 +3867,7 @@ ERROR(typealias_desugars_to_type_from_hidden_module,none,
       "C++ types from imported module %4 do not support library evolution|"
       "it was imported via the internal bridging header|"
       "%4 was not imported publicly|"
-      "it is a struct marked '@_implementationOnly'}5",
+      "%0 is marked '@_implementationOnly'}5",
       (const TypeAliasDecl *, StringRef, StringRef, unsigned, Identifier, unsigned))
 ERROR(conformance_from_implementation_only_module,none,
       "cannot use conformance of %0 to %1 %select{here|as property wrapper here|"
@@ -3884,7 +3884,7 @@ ERROR(conformance_from_implementation_only_module,none,
       "C++ types from imported module %3 do not support library evolution|"
       "it was imported via the internal bridging header|"
       "%3 was not imported publicly|"
-      "it is a struct marked '@_implementationOnly'}4",
+      "%0 is marked '@_implementationOnly'}4",
       (Type, Identifier, unsigned, Identifier, unsigned))
 NOTE(assoc_conformance_from_implementation_only_module,none,
      "in associated type %0 (inferred as %1)", (Type, Type))
@@ -3949,8 +3949,8 @@ ERROR(implementation_only_override_import_without_attr,none,
       "override of %kindonly0 imported as implementation-only must be declared "
       "'@_implementationOnly'",
       (const ValueDecl *))
-ERROR(implementation_only_on_structs_feature,none,
-      "'@_implementationOnly' on structs requires "
+ERROR(implementation_only_on_types_feature,none,
+      "'@_implementationOnly' on a type requires "
       "'-enable-experimental-feature CheckImplementationOnly'", ())
 
 ERROR(import_attr_conflict,none,
@@ -7353,7 +7353,7 @@ ERROR(inlinable_decl_ref_from_hidden_module,
       "C++ APIs from imported module %2 do not support library evolution|"
       "it was imported via the internal bridging header|"
       "%2 was not imported publicly|"
-      "it is a struct marked '@_implementationOnly'}3",
+      "%0 is marked '@_implementationOnly'}3",
       (const ValueDecl *, unsigned, Identifier, unsigned))
 
 ERROR(inlinable_typealias_desugars_to_type_from_hidden_module,
@@ -7366,7 +7366,7 @@ ERROR(inlinable_typealias_desugars_to_type_from_hidden_module,
       "C++ types from imported module %4 do not support library evolution|"
       "it was imported via the internal bridging header|"
       "%4 was not imported publicly|"
-      "it is a struct marked '@_implementationOnly'}5",
+      "%0 is marked '@_implementationOnly'}5",
       (const TypeAliasDecl *, StringRef, StringRef, unsigned, Identifier, unsigned))
 
 NOTE(missing_import_inserted,

lib/AST/Availability.cpp

@@ -1009,6 +1009,19 @@ bool swift::isExported(const ValueDecl *VD) {
     if (property->isLayoutExposedToClients(/*applyImplicit=*/true))
       return true;
 
+  // Is this a type exposed by default in a non-resilient module?
+  if (isa<NominalTypeDecl>(VD) &&
+      VD->getASTContext().LangOpts.hasFeature(
+          Feature::CheckImplementationOnly) &&
+      VD->getDeclContext()->getParentModule()->getResilienceStrategy() !=
+          ResilienceStrategy::Resilient &&
+      !VD->getAttrs().hasAttribute<ImplementationOnlyAttr>())
+    return true;
+
+  // Case of an enum not marked @_implementationOnly in a non-resilient module?
+  if (auto *EED = dyn_cast<EnumElementDecl>(VD))
+    return isExported(EED->getParentEnum());
+
   return false;
 }
 

lib/Sema/TypeCheckAttr.cpp

@@ -4995,12 +4995,12 @@ AttributeChecker::visitImplementationOnlyAttr(ImplementationOnlyAttr *attr) {
     return;
   }
 
-  // @_implementationOnly on structs only applies to non-public types.
   auto *VD = cast<ValueDecl>(D);
-  if (isa<StructDecl>(VD)) {
+
+  // @_implementationOnly on types only applies to non-public types.
+  if (isa<NominalTypeDecl>(D)) {
     if (!Ctx.LangOpts.hasFeature(Feature::CheckImplementationOnly)) {
-      diagnoseAndRemoveAttr(attr,
-          diag::implementation_only_on_structs_feature);
+      diagnoseAndRemoveAttr(attr, diag::implementation_only_on_types_feature);
       return;
     }
 

test/Sema/Inputs/implementation-only-imports/directs.swift

@@ -29,3 +29,10 @@ extension StructFromIndirect {
     set {}
   }
 }
+
+public struct RawTypeFromDirect : Equatable, ExpressibleByIntegerLiteral {
+  public typealias IntegerLiteralType = Int
+  public init(integerLiteral: Int) {}
+}
+
+public protocol ProtocolFromDirect { }