Sema: Relax distributed actor typechecking for swiftinterfaces.

Some decls that are expected to be synthesized for distributed actors are
printed explicitly in swiftinterfaces so diagnostics and assertions need to
take that possibility into account.

Resolves rdar://108533918

Author: tshortli

lib/Sema/CodeSynthesisDistributedActor.cpp

@@ -68,7 +68,6 @@ static VarDecl*
    if (!var->getInterfaceType()->isEqual(expectedType))
      return nullptr;
 
-   assert(var->isSynthesized() && "Expected compiler synthesized property");
    return var;
  }
 

lib/Sema/TypeCheckAttr.cpp

@@ -6666,9 +6666,8 @@ void AttributeChecker::visitNonisolatedAttr(NonisolatedAttr *attr) {
         // The synthesized "id" and "actorSystem" are the only exceptions,
         // because the implementation mirrors them.
         if (nominal->isDistributedActor() &&
-            !(var->isImplicit() &&
-              (var->getName() == Ctx.Id_id ||
-               var->getName() == Ctx.Id_actorSystem))) {
+            !(var->getName() == Ctx.Id_id ||
+              var->getName() == Ctx.Id_actorSystem)) {
           diagnoseAndRemoveAttr(attr,
                                 diag::nonisolated_distributed_actor_storage);
           return;

lib/Sema/TypeCheckDistributed.cpp

@@ -643,6 +643,12 @@ bool swift::checkDistributedActorProperty(VarDecl *var, bool diagnose) {
 void swift::checkDistributedActorProperties(const NominalTypeDecl *decl) {
   auto &C = decl->getASTContext();
 
+  auto sourceFile = decl->getDeclContext()->getParentSourceFile();
+  if (sourceFile && sourceFile->Kind == SourceFileKind::Interface) {
+    // Don't diagnose properties in swiftinterfaces.
+    return;
+  }
+
   if (isa<ProtocolDecl>(decl)) {
     // protocols don't matter for stored property checking
     return;

test/ModuleInterface/distributed-actor.swift

@@ -0,0 +1,47 @@
+// RUN: %empty-directory(%t)
+// RUN: %target-swift-emit-module-interface(%t/Library.swiftinterface) %s -module-name Library
+// RUN: %target-swift-typecheck-module-from-interface(%t/Library.swiftinterface) -module-name Library
+// RUN: %FileCheck %s < %t/Library.swiftinterface
+
+// REQUIRES: distributed
+
+import Distributed
+
+// CHECK:      #if compiler(>=5.3) && $Actors
+// CHECK-NEXT: @available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
+// CHECK-NEXT: distributed public actor DA {
+@available(SwiftStdlib 5.7, *)
+public distributed actor DA {
+  // CHECK: @_compilerInitialized nonisolated final public let id: Distributed.LocalTestingDistributedActorSystem.ActorID
+  // CHECK: nonisolated final public let actorSystem: Library.DA.ActorSystem
+  // CHECK: public typealias ActorSystem = Distributed.LocalTestingDistributedActorSystem
+  public typealias ActorSystem = LocalTestingDistributedActorSystem
+
+  // CHECK:       public static func resolve(id: Distributed.LocalTestingDistributedActorSystem.ActorID, using system: Library.DA.ActorSystem) throws -> Library.DA
+  // CHECK:       public typealias ID = Distributed.LocalTestingDistributedActorSystem.ActorID
+  // CHECK:       public typealias SerializationRequirement = any Swift.Decodable & Swift.Encodable
+  // CHECK:       {{@objc deinit|deinit}}
+  // CHECK:       nonisolated public var hashValue: Swift.Int {
+  // CHECK-NEXT:    get
+  // CHECK-NEXT:  }
+  // CHECK:       public init(actorSystem system: Library.DA.ActorSystem)
+  // CHECK:       @available(iOS 16.0, tvOS 16.0, watchOS 9.0, macOS 13.0, *)
+  // CHECK-NEXT:  @_semantics("defaultActor") nonisolated final public var unownedExecutor: _Concurrency.UnownedSerialExecutor {
+  // CHECK-NEXT:    get
+  // CHECK-NEXT:  }
+}
+// CHECK: #endif
+
+
+// CHECK:       #if compiler(>=5.3) && $Actors
+// CHECK-NEXT:  @available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
+// CHECK-NEXT:  extension Library.DA : Distributed.DistributedActor {}
+// CHECK-NEXT:  #endif
+// CHECK:       #if compiler(>=5.3) && $Actors
+// CHECK-NEXT:  @available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
+// CHECK-NEXT:  extension Library.DA : Swift.Encodable {}
+// CHECK-NEXT:  #endif
+// CHECK:       #if compiler(>=5.3) && $Actors
+// CHECK-NEXT:  @available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
+// CHECK-NEXT:  extension Library.DA : Swift.Decodable {}
+// CHECK-NEXT:  #endif