[TypeChecker] Distributed: Verify properties before attempting to synthesize a thunk

Author: xedin

lib/Sema/CodeSynthesisDistributedActor.cpp

@@ -792,6 +792,9 @@ FuncDecl *GetDistributedThunkRequest::evaluate(Evaluator &evaluator,
     if (!var->isDistributed())
       return nullptr;
 
+    if (checkDistributedActorProperty(var, /*diagnose=*/false))
+      return nullptr;
+
     distributedTarget = var->getAccessor(AccessorKind::Get);
   } else {
     distributedTarget = originator.get<AbstractFunctionDecl *>();
@@ -815,7 +818,8 @@ FuncDecl *GetDistributedThunkRequest::evaluate(Evaluator &evaluator,
   // we must avoid synthesis of the thunk because it'd also have errors,
   // giving an ugly user experience (errors in implicit code).
   if (distributedTarget->getInterfaceType()->hasError() ||
-      checkDistributedFunction(distributedTarget)) {
+      (!isa<AccessorDecl>(distributedTarget) &&
+       checkDistributedFunction(distributedTarget))) {
     return nullptr;
   }
 

lib/Sema/TypeCheckDistributed.cpp

@@ -26,6 +26,7 @@
 #include "swift/AST/TypeCheckRequests.h"
 #include "swift/AST/TypeVisitor.h"
 #include "swift/AST/ExistentialLayout.h"
+#include "swift/Basic/Defer.h"
 
 using namespace swift;
 
@@ -598,23 +599,26 @@ bool swift::checkDistributedActorProperty(VarDecl *var, bool diagnose) {
 
   /// === Check if the declaration is a valid combination of attributes
   if (var->isStatic()) {
-    var->diagnose(diag::distributed_property_cannot_be_static,
-                      var->getName());
+    if (diagnose)
+      var->diagnose(diag::distributed_property_cannot_be_static,
+                    var->getName());
     // TODO(distributed): fixit, offer removing the static keyword
     return true;
   }
 
   // it is not a computed property
   if (var->isLet() || var->hasStorageOrWrapsStorage()) {
-    var->diagnose(diag::distributed_property_can_only_be_computed,
-                  var->getDescriptiveKind(), var->getName());
+    if (diagnose)
+      var->diagnose(diag::distributed_property_can_only_be_computed,
+                    var->getDescriptiveKind(), var->getName());
     return true;
   }
 
   // distributed properties cannot have setters
   if (var->getWriteImpl() != swift::WriteImplKind::Immutable) {
-    var->diagnose(diag::distributed_property_can_only_be_computed_get_only,
-                  var->getName());
+    if (diagnose)
+      var->diagnose(diag::distributed_property_can_only_be_computed_get_only,
+                    var->getName());
     return true;
   }