Merge pull request #5782 from DougGregor/conforms-to-protocol-api

Author: swift-ci

include/swift/AST/KnownIdentifiers.def

@@ -45,6 +45,7 @@ IDENTIFIER(hashValue)
 IDENTIFIER(init)
 IDENTIFIER(initStorage)
 IDENTIFIER(initialValue)
+IDENTIFIER(Key)
 IDENTIFIER(makeIterator)
 IDENTIFIER(Iterator)
 IDENTIFIER(load)

include/swift/AST/ProtocolConformance.h

@@ -160,7 +160,7 @@ class alignas(1 << DeclAlignInBits) ProtocolConformance {
 
   static Type
   getTypeWitnessByName(Type type,
-                       ProtocolConformance *conformance,
+                       ProtocolConformanceRef conformance,
                        Identifier name,
                        LazyResolver *resolver);
 

lib/AST/ASTContext.cpp

@@ -3883,7 +3883,7 @@ Type ASTContext::getBridgedToObjC(const DeclContext *dc, Type type,
     // Find the Objective-C class type we bridge to.
     if (conformance->isConcrete()) {
       return ProtocolConformance::getTypeWitnessByName(
-               type, conformance->getConcrete(), Id_ObjectiveCType,
+               type, *conformance, Id_ObjectiveCType,
                getLazyResolver());
     } else {
       return type->castTo<ArchetypeType>()->getNestedType(Id_ObjectiveCType)

lib/AST/ProtocolConformance.cpp

@@ -156,7 +156,7 @@ ProtocolConformance::getTypeWitness(AssociatedTypeDecl *assocType,
 
 Type
 ProtocolConformance::getTypeWitnessByName(Type type,
-                                          ProtocolConformance *conformance,
+                                          ProtocolConformanceRef conformance,
                                           Identifier name,
                                           LazyResolver *resolver) {
   // For an archetype, retrieve the nested type with the appropriate
@@ -167,21 +167,25 @@ ProtocolConformance::getTypeWitnessByName(Type type,
 
   // Find the named requirement.
   AssociatedTypeDecl *assocType = nullptr;
-  auto members = conformance->getProtocol()->lookupDirect(name);
+  auto members = conformance.getRequirement()->lookupDirect(name);
   for (auto member : members) {
     assocType = dyn_cast<AssociatedTypeDecl>(member);
     if (assocType)
       break;
   }
 
+  // FIXME: Shouldn't this be a hard error?
   if (!assocType)
     return nullptr;
-  
-  assert(conformance && "Missing conformance information");
-  if (!conformance->hasTypeWitness(assocType, resolver)) {
+
+  if (conformance.isAbstract())
+    return DependentMemberType::get(type, assocType);
+
+  auto concrete = conformance.getConcrete();
+  if (!concrete->hasTypeWitness(assocType, resolver)) {
     return nullptr;
   }
-  return conformance->getTypeWitness(assocType, resolver).getReplacement();
+  return concrete->getTypeWitness(assocType, resolver).getReplacement();
 }
 
 Witness ProtocolConformance::getWitness(ValueDecl *requirement,

lib/PrintAsObjC/PrintAsObjC.cpp

@@ -875,7 +875,7 @@ class ObjCPrinter : private DeclVisitor<ObjCPrinter>,
     auto conformance = conformances.front();
     Type objcType = ProtocolConformance::getTypeWitnessByName(
                       nominal->getDeclaredType(),
-                      conformance,
+                      ProtocolConformanceRef(conformance),
                       ctx.Id_ObjectiveCType,
                       nullptr);
     if (!objcType) return nullptr;

lib/SIL/Bridging.cpp

@@ -223,7 +223,8 @@ Type TypeConverter::getLoweredCBridgedType(AbstractionPattern pattern,
     assert(conformance && "Missing conformance?");
     Type bridgedTy =
       ProtocolConformance::getTypeWitnessByName(
-        t, conformance, M.getASTContext().Id_ObjectiveCType,
+        t, ProtocolConformanceRef(conformance),
+        M.getASTContext().Id_ObjectiveCType,
         nullptr);
     assert(bridgedTy && "Missing _ObjectiveCType witness?");
     if (bridgedCollectionsAreOptional && clangTy)