AST/Sema: Fix a couple of minor issues with tuple conformances and add a new test case

lib/AST/Type.cpp

@@ -261,6 +261,7 @@ bool CanType::isReferenceTypeImpl(CanType type, const GenericSignatureImpl *sig,
   case TypeKind::PackExpansion:
   case TypeKind::PackElement:
   case TypeKind::SILPack:
+  case TypeKind::BuiltinTuple:
 #define REF_STORAGE(Name, ...) \
   case TypeKind::Name##Storage:
 #include "swift/AST/ReferenceStorage.def"
@@ -270,8 +271,6 @@ bool CanType::isReferenceTypeImpl(CanType type, const GenericSignatureImpl *sig,
   case TypeKind::DependentMember:
     assert(sig && "dependent types can't answer reference semantics query");
     return sig->requiresClass(type);
-  case TypeKind::BuiltinTuple:
-    llvm_unreachable("Should not get a BuiltinTupleType here");
   }
 
   llvm_unreachable("Unhandled type kind!");

lib/Sema/TypeCheckDecl.cpp

@@ -2029,10 +2029,13 @@ bool swift::isMemberOperator(FuncDecl *decl, Type type) {
     return true;
 
   auto *DC = decl->getDeclContext();
+
   auto selfNominal = DC->getSelfNominalTypeDecl();
 
   // Check the parameters for a reference to 'Self'.
   bool isProtocol = isa_and_nonnull<ProtocolDecl>(selfNominal);
+  bool isTuple = isa_and_nonnull<BuiltinTupleDecl>(selfNominal);
+
   for (auto param : *decl->getParameters()) {
     // Look through a metatype reference, if there is one.
     auto paramType = param->getInterfaceType()->getMetatypeInstanceType();
@@ -2057,11 +2060,12 @@ bool swift::isMemberOperator(FuncDecl *decl, Type type) {
         if (selfNominal == existential->getConstraintType()->getAnyNominal())
           return true;
       }
+    }
 
-      // For a protocol, is it the 'Self' type parameter?
-      if (auto genericParam = paramType->getAs<GenericTypeParamType>())
-        if (genericParam->isEqual(DC->getSelfInterfaceType()))
-          return true;
+    if (isProtocol || isTuple) {
+      // For a protocol or tuple extension, is it the 'Self' type parameter?
+      if (paramType->isEqual(DC->getSelfInterfaceType()))
+        return true;
     }
   }
 

test/Generics/tuple-conformances.swift

@@ -34,3 +34,28 @@ func useConformance() {
 
   (1, 2, 3).f()
 }
+
+////
+
+extension Builtin.TheTupleType: Equatable where repeat each Elements: Equatable {
+  public static func ==(lhs: Self, rhs: Self) -> Bool {
+    var result = true
+    func update<E: Equatable>(lhs: E, rhs: E) {
+      result = result && (lhs == rhs)
+    }
+
+    repeat update(lhs: each lhs, rhs: each rhs)
+    return result
+  }
+}
+
+extension Builtin.TheTupleType: Hashable where repeat each Elements: Hashable {
+  public func hash(into hasher: inout Hasher) {
+    repeat (each self).hash(into: &hasher)
+  }
+
+  // FIXME: This should be unnecessary
+  public var hashValue: Int {
+    return 0
+  }
+}