Unqualified lookup fixes, part 2

lib/AST/NameLookup.cpp

@@ -999,8 +999,6 @@ UnqualifiedLookup::UnqualifiedLookup(DeclName Name, DeclContext *DC,
 
           // Look in the generic parameters after checking our local declaration.
           GenericParams = AFD->getGenericParams();
-        } else if (auto *SD = dyn_cast<SubscriptDecl>(DC)) {
-          GenericParams = SD->getGenericParams();
         } else if (auto *ACE = dyn_cast<AbstractClosureExpr>(DC)) {
           // Look for local variables; normally, the parser resolves these
           // for us, but it can't do the right thing inside local types.
@@ -1042,12 +1040,14 @@ UnqualifiedLookup::UnqualifiedLookup(DeclName Name, DeclContext *DC,
           continue;
         } else {
           assert(isa<TopLevelCodeDecl>(DC) || isa<Initializer>(DC) ||
-                 isa<TypeAliasDecl>(DC));
+                 isa<TypeAliasDecl>(DC) || isa<SubscriptDecl>(DC));
           if (!isCascadingUse.hasValue())
             isCascadingUse = DC->isCascadingContextForLookup(false);
         }
 
-        // Check the generic parameters for something with the given name.
+        // If we're inside a function context, we've already moved to
+        // the parent DC, so we have to check the function's generic
+        // parameters first.
         if (GenericParams) {
           namelookup::FindLocalVal localVal(SM, Loc, Consumer);
           localVal.checkGenericParams(GenericParams);
@@ -1056,6 +1056,30 @@ UnqualifiedLookup::UnqualifiedLookup(DeclName Name, DeclContext *DC,
             return;
         }
 
+        // Check the generic parameters of our context.
+        GenericParamList *dcGenericParams = nullptr;
+        if (auto nominal = dyn_cast<NominalTypeDecl>(DC))
+          dcGenericParams = nominal->getGenericParams();
+        else if (auto ext = dyn_cast<ExtensionDecl>(DC))
+          dcGenericParams = ext->getGenericParams();
+        else if (auto subscript = dyn_cast<SubscriptDecl>(DC))
+          dcGenericParams = subscript->getGenericParams();
+
+        while (dcGenericParams) {
+          namelookup::FindLocalVal localVal(SM, Loc, Consumer);
+          localVal.checkGenericParams(dcGenericParams);
+
+          if (shouldReturnBasedOnResults())
+            return;
+
+          // Extensions of nested types have multiple levels of
+          // generic parameters, so we have to visit them explicitly.
+          if (!isa<ExtensionDecl>(DC))
+            break;
+
+          dcGenericParams = dcGenericParams->getOuterParameters();
+        }
+
         if (BaseDC && !lookupDecls.empty()) {
           NLOptions options = baseNLOptions;
           if (isCascadingUse.getValue())
@@ -1071,12 +1095,9 @@ UnqualifiedLookup::UnqualifiedLookup(DeclName Name, DeclContext *DC,
             // Classify this declaration.
             FoundAny = true;
 
-            // Types are local or metatype members.
+            // Types are formally members of the metatype.
             if (auto TD = dyn_cast<TypeDecl>(Result)) {
-              if (isa<GenericTypeParamDecl>(TD))
-                Results.push_back(LookupResultEntry(Result));
-              else
-                Results.push_back(LookupResultEntry(MetaBaseDC, Result));
+              Results.push_back(LookupResultEntry(MetaBaseDC, Result));
               continue;
             }
 
@@ -1108,29 +1129,6 @@ UnqualifiedLookup::UnqualifiedLookup(DeclName Name, DeclContext *DC,
           }
         }
 
-        // Check the generic parameters if our context is a generic type or
-        // extension thereof.
-        GenericParamList *dcGenericParams = nullptr;
-        if (auto nominal = dyn_cast<NominalTypeDecl>(DC))
-          dcGenericParams = nominal->getGenericParams();
-        else if (auto ext = dyn_cast<ExtensionDecl>(DC))
-          dcGenericParams = ext->getGenericParams();
-        else if (auto subscript = dyn_cast<SubscriptDecl>(DC))
-          dcGenericParams = subscript->getGenericParams();
-
-        while (dcGenericParams) {
-          namelookup::FindLocalVal localVal(SM, Loc, Consumer);
-          localVal.checkGenericParams(dcGenericParams);
-
-          if (shouldReturnBasedOnResults())
-            return;
-
-          if (!isa<ExtensionDecl>(DC))
-            break;
-
-          dcGenericParams = dcGenericParams->getOuterParameters();
-        }
-
         DC = DC->getParentForLookup();
       }
 

lib/Sema/TypeCheckDecl.cpp

@@ -2057,7 +2057,7 @@ static NominalTypeDecl *resolveSingleNominalTypeDecl(
 
   TypeResolutionOptions options = TypeResolverContext::TypeAliasDecl;
   options |= flags;
-  if (tc.validateType(typeLoc, TypeResolution::forContextual(DC), options))
+  if (tc.validateType(typeLoc, TypeResolution::forInterface(DC), options))
     return nullptr;
 
   return typeLoc.getType()->getAnyNominal();
@@ -3469,7 +3469,7 @@ static void validateTypealiasType(TypeChecker &tc, TypeAliasDecl *typeAlias) {
   }
 
   if (tc.validateType(typeAlias->getUnderlyingTypeLoc(),
-                      TypeResolution::forContextual(typeAlias), options)) {
+                      TypeResolution::forInterface(typeAlias), options)) {
     typeAlias->setInvalid();
     typeAlias->getUnderlyingTypeLoc().setInvalidType(tc.Context);
   }

test/NameBinding/name_lookup.swift

@@ -601,3 +601,11 @@ func test3() {
     _ = b
   }
 }
+
+// rdar://problem/22587551
+class ShadowingGenericParameter<T> {
+  typealias T = Int
+  func foo (t : T) {}
+}
+
+_ = ShadowingGenericParameter<String>().foo(t: "hi")

test/Sema/circular_decl_checking.swift

@@ -66,7 +66,8 @@ class X {
 
 // <rdar://problem/17144076> recursive typealias causes a segfault in the type checker
 struct SomeStruct<A> {
-  typealias A = A // expected-error {{type alias 'A' references itself}}
+  typealias A = A // this is OK now -- the underlying type is the generic parameter 'A'
+  typealias B = B // expected-error {{type alias 'B' references itself}}
   // expected-note@-1 {{type declared here}}
 }
 

test/api-digester/Outputs/stability-stdlib-source.swift.expected

@@ -10,6 +10,53 @@
 /* Renamed Decls */
 
 /* Type Changes */
+Func AnyBidirectionalCollection.formIndex(_:offsetBy:) has parameter 0 changing from Default to InOut
+Func AnyBidirectionalCollection.formIndex(_:offsetBy:limitedBy:) has parameter 0 changing from Default to InOut
+Func AnyBidirectionalCollection.formIndex(after:) has parameter 0 changing from Default to InOut
+Func AnyBidirectionalCollection.formIndex(before:) has parameter 0 changing from Default to InOut
+Func AnyCollection.formIndex(_:offsetBy:) has parameter 0 changing from Default to InOut
+Func AnyCollection.formIndex(_:offsetBy:limitedBy:) has parameter 0 changing from Default to InOut
+Func AnyCollection.formIndex(after:) has parameter 0 changing from Default to InOut
+Func AnyRandomAccessCollection.formIndex(_:offsetBy:) has parameter 0 changing from Default to InOut
+Func AnyRandomAccessCollection.formIndex(_:offsetBy:limitedBy:) has parameter 0 changing from Default to InOut
+Func AnyRandomAccessCollection.formIndex(after:) has parameter 0 changing from Default to InOut
+Func AnyRandomAccessCollection.formIndex(before:) has parameter 0 changing from Default to InOut
+Func Array.append(_:) has parameter 0 changing from Default to Owned
+Func Array.append(_:) has parameter 0 type change from Array<Element>.Element to Element
+Func Array.insert(_:at:) has parameter 0 changing from Default to Owned
+Func Array.insert(_:at:) has parameter 0 type change from Array<Element>.Element to Element
+Func ArraySlice.append(_:) has parameter 0 changing from Default to Owned
+Func ArraySlice.append(_:) has parameter 0 type change from ArraySlice<Element>.Element to Element
+Func ArraySlice.insert(_:at:) has parameter 0 changing from Default to Owned
+Func ArraySlice.insert(_:at:) has parameter 0 type change from ArraySlice<Element>.Element to Element
+Func ContiguousArray.append(_:) has parameter 0 changing from Default to Owned
+Func ContiguousArray.append(_:) has parameter 0 type change from ContiguousArray<Element>.Element to Element
+Func ContiguousArray.insert(_:at:) has parameter 0 changing from Default to Owned
+Func ContiguousArray.insert(_:at:) has parameter 0 type change from ContiguousArray<Element>.Element to Element
+Func DefaultIndices.formIndex(after:) has parameter 0 changing from Default to InOut
+Func DefaultIndices.formIndex(before:) has parameter 0 changing from Default to InOut
+Func Dictionary.updateValue(_:forKey:) has parameter 0 changing from Default to Owned
+Func Dictionary.updateValue(_:forKey:) has parameter 0 type change from Dictionary<Key, Value>.Value to Value
+Func LazyFilterCollection.formIndex(_:offsetBy:) has parameter 0 changing from Default to InOut
+Func LazyFilterCollection.formIndex(_:offsetBy:limitedBy:) has parameter 0 changing from Default to InOut
+Func LazyFilterCollection.formIndex(after:) has parameter 0 changing from Default to InOut
+Func LazyFilterCollection.formIndex(before:) has parameter 0 changing from Default to InOut
+Func LazyMapCollection.formIndex(after:) has parameter 0 changing from Default to InOut
+Func LazyMapCollection.formIndex(before:) has parameter 0 changing from Default to InOut
+Func Set.insert(_:) has parameter 0 changing from Default to Owned
+Func Set.insert(_:) has parameter 0 type change from Set<Element>.Element to Element
+Func Set.update(with:) has parameter 0 changing from Default to Owned
+Func Set.update(with:) has parameter 0 type change from Set<Element>.Element to Element
+Func Slice.formIndex(after:) has parameter 0 changing from Default to InOut
+Func Slice.formIndex(before:) has parameter 0 changing from Default to InOut
+Func String.UTF16View.Indices.formIndex(after:) has parameter 0 changing from Default to InOut
+Func String.UTF16View.Indices.formIndex(before:) has parameter 0 changing from Default to InOut
+Func Substring.UTF16View.formIndex(after:) has parameter 0 changing from Default to InOut
+Func Substring.UTF16View.formIndex(before:) has parameter 0 changing from Default to InOut
+Func Substring.UTF8View.formIndex(after:) has parameter 0 changing from Default to InOut
+Func Substring.UTF8View.formIndex(before:) has parameter 0 changing from Default to InOut
+Func Substring.UnicodeScalarView.formIndex(after:) has parameter 0 changing from Default to InOut
+Func Substring.UnicodeScalarView.formIndex(before:) has parameter 0 changing from Default to InOut
 
 /* Decl Attribute changes */
 

test/decl/protocol/req/associated_type_inference.swift

@@ -508,3 +508,22 @@ protocol P20 {
 struct S19 : P20 {  // expected-error{{type 'S19' does not conform to protocol 'P20'}}
   typealias TT = Int?
 }
+
+// rdar://problem/44777661
+struct S30<T> where T : P30 {}
+
+protocol P30 {
+  static func bar()
+}
+
+protocol P31 {
+  associatedtype T : P30
+}
+
+extension S30 : P31 where T : P31 {}
+
+extension S30 {
+  func foo() {
+    T.bar()
+  }
+}

test/decl/typealias/protocol.swift

@@ -144,13 +144,18 @@ protocol P3 {
 
 // Test for not crashing on recursive aliases
 protocol Circular {
-  typealias Y = Self.Y // expected-error {{type alias 'Y' is not a member type of 'Self'}}
+  typealias Y = Self.Y // expected-error {{'Y' is not a member type of 'Self'}}
+  // expected-note@-1 {{did you mean 'Y'?}}
 
   typealias Y2 = Y2 // expected-error {{type alias 'Y2' references itself}}
   // expected-note@-1 {{type declared here}}
+  // expected-note@-2 {{did you mean 'Y2'?}}
 
   typealias Y3 = Y4 // expected-note {{type declared here}}
+  // expected-note@-1 {{did you mean 'Y3'?}}
+
   typealias Y4 = Y3 // expected-error {{type alias 'Y3' references itself}}
+  // expected-note@-1 {{did you mean 'Y4'?}}
 }
 
 // Qualified and unqualified references to protocol typealiases from concrete type

tools/swift-api-digester/ModuleAnalyzerNodes.cpp

@@ -654,13 +654,29 @@ static bool hasSameContents(ArrayRef<StringRef> Left,
   return LeftMinusRight.empty() && RightMinusLeft.empty();
 }
 
-bool static isSDKNodeEqual(SDKContext &Ctx, const SDKNode &L, const SDKNode &R) {
+static bool hasSameParameterFlags(const SDKNodeType *Left, const SDKNodeType *Right) {
+  if (Left->hasDefaultArgument() != Right->hasDefaultArgument())
+    return false;
+  if (Left->getParamValueOwnership() != Right->getParamValueOwnership())
+    return false;
+
+  return true;
+}
+
+static bool isSDKNodeEqual(SDKContext &Ctx, const SDKNode &L, const SDKNode &R) {
   auto *LeftAlias = dyn_cast<SDKNodeTypeAlias>(&L);
   auto *RightAlias = dyn_cast<SDKNodeTypeAlias>(&R);
   if (LeftAlias || RightAlias) {
+    auto Left = L.getAs<SDKNodeType>();
+    auto Right = R.getAs<SDKNodeType>();
+
+    // First compare the parameter attributes.
+    if (!hasSameParameterFlags(Left, Right))
+      return false;
+
     // Comparing the underlying types if any of the inputs are alias.
-    const SDKNode *Left = LeftAlias ? LeftAlias->getUnderlyingType() : &L;
-    const SDKNode *Right = RightAlias ? RightAlias->getUnderlyingType() : &R;
+    Left = LeftAlias ? LeftAlias->getUnderlyingType() : Left;
+    Right = RightAlias ? RightAlias->getUnderlyingType() : Right;
     return *Left == *Right;
   }
 
@@ -676,9 +692,7 @@ bool static isSDKNodeEqual(SDKContext &Ctx, const SDKNode &L, const SDKNode &R)
       auto Right = R.getAs<SDKNodeType>();
       if (Left->hasAttributeChange(*Right))
         return false;
-      if (Left->hasDefaultArgument() != Right->hasDefaultArgument())
-        return false;
-      if (Left->getParamValueOwnership() != Right->getParamValueOwnership())
+      if (!hasSameParameterFlags(Left, Right))
         return false;
       if (Left->getPrintedName() == Right->getPrintedName())
         return true;
@@ -740,8 +754,6 @@ bool static isSDKNodeEqual(SDKContext &Ctx, const SDKNode &L, const SDKNode &R)
         if (auto *Right = dyn_cast<SDKNodeDeclSubscript>(&R)) {
           if (Left->hasSetter() != Right->hasSetter())
             return false;
-          if (Left->hasStorage() != Right->hasStorage())
-            return false;
         }
       }
       LLVM_FALLTHROUGH;
@@ -776,7 +788,7 @@ bool static isSDKNodeEqual(SDKContext &Ctx, const SDKNode &L, const SDKNode &R)
     }
   }
 
-  llvm_unreachable("Unhanlded SDKNodeKind in switch.");
+  llvm_unreachable("Unhandled SDKNodeKind in switch.");
 }
 
 bool SDKContext::isEqual(const SDKNode &Left, const SDKNode &Right) {
@@ -1166,16 +1178,15 @@ SwiftDeclCollector::constructTypeNode(Type T, TypeInitInfo Info) {
   if (Ctx.checkingABI()) {
     T = T->getCanonicalType();
   }
-  SDKNode* Root = SDKNodeInitInfo(Ctx, T, Info).createSDKNode(SDKNodeKind::TypeNominal);
 
   if (auto NAT = dyn_cast<NameAliasType>(T.getPointer())) {
-    SDKNode* Root = SDKNodeInitInfo(Ctx, T).createSDKNode(SDKNodeKind::TypeAlias);
-    Root->addChild(constructTypeNode(NAT->getCanonicalType()));
+    SDKNode* Root = SDKNodeInitInfo(Ctx, T, Info).createSDKNode(SDKNodeKind::TypeAlias);
+    Root->addChild(constructTypeNode(NAT->getSinglyDesugaredType()));
     return Root;
   }
 
   if (auto Fun = T->getAs<AnyFunctionType>()) {
-    SDKNode* Root = SDKNodeInitInfo(Ctx, T).createSDKNode(SDKNodeKind::TypeFunc);
+    SDKNode* Root = SDKNodeInitInfo(Ctx, T, Info).createSDKNode(SDKNodeKind::TypeFunc);
 
     // Still, return type first
     Root->addChild(constructTypeNode(Fun->getResult()));
@@ -1187,6 +1198,8 @@ SwiftDeclCollector::constructTypeNode(Type T, TypeInitInfo Info) {
     return Root;
   }
 
+  SDKNode* Root = SDKNodeInitInfo(Ctx, T, Info).createSDKNode(SDKNodeKind::TypeNominal);
+
   // Keep paren type as a stand-alone level.
   if (auto *PT = dyn_cast<ParenType>(T.getPointer())) {
     Root->addChild(constructTypeNode(PT->getSinglyDesugaredType()));

tools/swift-api-digester/swift-api-digester.cpp

@@ -1293,7 +1293,7 @@ class InterfaceTypeChangeDetector {
     if (IsVisitingLeft &&
         Node->getPrintedName() != Counter->getPrintedName() &&
         (Node->getName() != Counter->getName() ||
-        Node->getChildrenCount() != Counter->getChildrenCount())) {
+         Node->getChildrenCount() != Counter->getChildrenCount())) {
       Node->annotate(NodeAnnotation::TypeRewritten);
       Node->annotate(NodeAnnotation::TypeRewrittenLeft, Node->getPrintedName());
       Node->annotate(NodeAnnotation::TypeRewrittenRight,