Merge pull request swiftlang#36696 from hborla/wrapped-parameter-accessor-synthesis

[Property Wrappers] Fix accessor synthesis of wrapped parameters that infer the property wrapper attribute.

Author: hborla

lib/Sema/CSApply.cpp

@@ -8092,17 +8092,30 @@ namespace {
 
         // Set the interface type of each property wrapper synthesized var
         auto *backingVar = param->getPropertyWrapperBackingProperty();
-        backingVar->setInterfaceType(
-            solution.simplifyType(solution.getType(backingVar))->mapTypeOutOfContext());
+        auto backingType =
+            solution.simplifyType(solution.getType(backingVar))->mapTypeOutOfContext();
+        backingVar->setInterfaceType(backingType);
 
         if (auto *projectionVar = param->getPropertyWrapperProjectionVar()) {
           projectionVar->setInterfaceType(
               solution.simplifyType(solution.getType(projectionVar)));
         }
 
         auto *wrappedValueVar = param->getPropertyWrapperWrappedValueVar();
-        wrappedValueVar->setInterfaceType(
-            solution.simplifyType(solution.getType(wrappedValueVar)));
+        auto wrappedValueType = solution.simplifyType(solution.getType(wrappedValueVar));
+        wrappedValueVar->setInterfaceType(wrappedValueType->getWithoutSpecifierType());
+
+        if (param->hasImplicitPropertyWrapper()) {
+          if (wrappedValueType->is<LValueType>())
+            wrappedValueVar->setImplInfo(StorageImplInfo::getMutableComputed());
+
+          // Add an explicit property wrapper attribute, which is needed for
+          // synthesizing the accessors.
+          auto &context = wrappedValueVar->getASTContext();
+          auto *typeExpr = TypeExpr::createImplicit(backingType, context);
+          auto *attr = CustomAttr::create(context, SourceLoc(), typeExpr, /*implicit=*/true);
+          wrappedValueVar->getAttrs().add(attr);
+        }
       }
 
       TypeChecker::checkParameterList(closure->getParameters(), closure);

lib/Sema/CSSimplify.cpp

@@ -8212,7 +8212,12 @@ ConstraintSystem::simplifyPropertyWrapperConstraint(
   }
 
   auto resolvedType = wrapperType->getTypeOfMember(DC->getParentModule(), typeInfo.valueVar);
-  addConstraint(ConstraintKind::Equal, wrappedValueType, resolvedType, locator);
+  if (typeInfo.valueVar->isSettable(nullptr) && typeInfo.valueVar->isSetterAccessibleFrom(DC) &&
+      !typeInfo.valueVar->isSetterMutating()) {
+    resolvedType = LValueType::get(resolvedType);
+  }
+
+  addConstraint(ConstraintKind::Bind, wrappedValueType, resolvedType, locator);
 
   return SolutionKind::Solved;
 }
@@ -8390,7 +8395,8 @@ bool ConstraintSystem::resolveClosure(TypeVariableType *typeVar,
 
       if (paramDecl->hasImplicitPropertyWrapper()) {
         backingType = getContextualParamAt(i)->getPlainType();
-        wrappedValueType = createTypeVariable(getConstraintLocator(locator), TVO_CanBindToHole);
+        wrappedValueType = createTypeVariable(getConstraintLocator(locator),
+                                              TVO_CanBindToHole | TVO_CanBindToLValue);
       } else {
         auto *wrapperAttr = paramDecl->getAttachedPropertyWrappers().front();
         auto wrapperType = paramDecl->getAttachedPropertyWrapperType(0);

test/SILGen/property_wrapper_parameter.swift

@@ -183,7 +183,7 @@ func testImplicitPropertyWrapper(projection: ProjectionWrapper<Int>) {
   // CHECK: sil private [ossa] @$s26property_wrapper_parameter27testImplicitPropertyWrapper10projectionyAA010ProjectionG0VySiG_tFyAFcfu_yAFcfU_6$valueL_AFvg : $@convention(thin) (ProjectionWrapper<Int>) -> ProjectionWrapper<Int>
 
   // getter of value #1 in closure #1 in implicit closure #1 in testImplicitPropertyWrapper(projection:)
-  // CHECK: sil private [ossa] @$s26property_wrapper_parameter27testImplicitPropertyWrapper10projectionyAA010ProjectionG0VySiG_tFyAFcfu_yAFcfU_5valueL_Sivg : $@convention(thin) () -> Int
+  // CHECK: sil private [ossa] @$s26property_wrapper_parameter27testImplicitPropertyWrapper10projectionyAA010ProjectionG0VySiG_tFyAFcfu_yAFcfU_5valueL_Sivg : $@convention(thin) (ProjectionWrapper<Int>) -> Int
 
   let _: (ProjectionWrapper<Int>) -> (Int, ProjectionWrapper<Int>) = { $value in
     (value, $value)
@@ -202,7 +202,7 @@ func testImplicitPropertyWrapper(projection: ProjectionWrapper<Int>) {
   // CHECK: sil private [ossa] @$s26property_wrapper_parameter27testImplicitPropertyWrapper10projectionyAA010ProjectionG0VySiG_tFSi_AFtAFcfu0_Si_AFtAFcfU0_6$valueL_AFvg : $@convention(thin) (ProjectionWrapper<Int>) -> ProjectionWrapper<Int>
 
   // getter of value #1 in closure #2 in implicit closure #2 in testImplicitPropertyWrapper(projection:)
-  // CHECK: sil private [ossa] @$s26property_wrapper_parameter27testImplicitPropertyWrapper10projectionyAA010ProjectionG0VySiG_tFSi_AFtAFcfu0_Si_AFtAFcfU0_5valueL_Sivg : $@convention(thin) () -> Int
+  // CHECK: sil private [ossa] @$s26property_wrapper_parameter27testImplicitPropertyWrapper10projectionyAA010ProjectionG0VySiG_tFSi_AFtAFcfu0_Si_AFtAFcfU0_5valueL_Sivg : $@convention(thin) (ProjectionWrapper<Int>) -> Int
 }
 
 @propertyWrapper
@@ -247,3 +247,39 @@ public func publicFunc(@PublicWrapper value: String) {
   // CHECK: function_ref @$s26property_wrapper_parameter10publicFunc5valueyAA13PublicWrapperVySSG_tFACL_SSvpfP : $@convention(thin) (@owned String) -> @owned PublicWrapper<String>
   // CHECK: function_ref @$s26property_wrapper_parameter10publicFunc5valueyAA13PublicWrapperVySSG_tF : $@convention(thin) (@guaranteed PublicWrapper<String>) -> ()
 }
+
+@propertyWrapper
+struct NonmutatingSetter<Value> {
+  var wrappedValue: Value {
+    // CHECK-LABEL: sil hidden [ossa] @$s26property_wrapper_parameter17NonmutatingSetterV12wrappedValuexvg : $@convention(method) <Value> (NonmutatingSetter<Value>) -> @out Value
+    get { fatalError() }
+    // CHECK-LABEL: sil hidden [ossa] @$s26property_wrapper_parameter17NonmutatingSetterV12wrappedValuexvs : $@convention(method) <Value> (@in Value, NonmutatingSetter<Value>) -> ()
+    nonmutating set {}
+  }
+  var projectedValue: Self { self }
+  init(wrappedValue: Value) {}
+  init(projectedValue: Self) {}
+}
+
+func genericClosure<T>(arg: T, _ closure: (T) -> Int) {}
+
+// CHECK-LABEL: sil hidden [ossa] @$s26property_wrapper_parameter30testNonmutatingSetterSynthesis5valueyAA0eF0VySiG_tF : $@convention(thin) (NonmutatingSetter<Int>) -> ()
+func testNonmutatingSetterSynthesis(@NonmutatingSetter value: Int) {
+  genericClosure(arg: $value) { $value in
+    (value = 10, value).1
+  }
+
+  // closure #1 in implicit closure #1 in testNonmutatingSetterSynthesis(value:)
+  // CHECK-LABEL: sil private [ossa] @$s26property_wrapper_parameter30testNonmutatingSetterSynthesis5valueyAA0eF0VySiG_tFSiAFcfu_SiAFcfU_ : $@convention(thin) (NonmutatingSetter<Int>) -> Int
+  // CHECK: function_ref @$s26property_wrapper_parameter30testNonmutatingSetterSynthesis5valueyAA0eF0VySiG_tFSiAFcfu_SiAFcfU_ACL_Sivs : $@convention(thin) (Int, NonmutatingSetter<Int>) -> ()
+  // CHECK: function_ref @$s26property_wrapper_parameter30testNonmutatingSetterSynthesis5valueyAA0eF0VySiG_tFSiAFcfu_SiAFcfU_ACL_Sivg : $@convention(thin) (NonmutatingSetter<Int>) -> Int
+  // CHECK: return
+
+  // getter of value #1 in closure #1 in implicit closure #1 in testNonmutatingSetterSynthesis(value:)
+  // CHECK-LABEL: sil private [ossa] @$s26property_wrapper_parameter30testNonmutatingSetterSynthesis5valueyAA0eF0VySiG_tFSiAFcfu_SiAFcfU_ACL_Sivg : $@convention(thin) (NonmutatingSetter<Int>) -> Int
+  // CHECK: function_ref @$s26property_wrapper_parameter17NonmutatingSetterV12wrappedValuexvg : $@convention(method) <τ_0_0> (NonmutatingSetter<τ_0_0>) -> @out τ_0_0
+
+  // setter of value #1 in closure #1 in implicit closure #1 in testNonmutatingSetterSynthesis(value:)
+  // CHECK-LABEL: sil private [ossa] @$s26property_wrapper_parameter30testNonmutatingSetterSynthesis5valueyAA0eF0VySiG_tFSiAFcfu_SiAFcfU_ACL_Sivs : $@convention(thin) (Int, NonmutatingSetter<Int>) -> ()
+  // CHECK: function_ref @$s26property_wrapper_parameter17NonmutatingSetterV12wrappedValuexvs : $@convention(method) <τ_0_0> (@in τ_0_0, NonmutatingSetter<τ_0_0>) -> ()
+}