Swift NilLiteralConvertible to an initializer requirement

Swift SVN r21980

include/swift/AST/KnownIdentifiers.def

@@ -62,7 +62,7 @@ IDENTIFIER_WITH_NAME(MaxBuiltinIntegerType, "_MaxBuiltinIntegerType")
 IDENTIFIER(IntegerLiteralType)
 IDENTIFIER_WITH_NAME(AllZeros, "allZeros")
 IDENTIFIER_WITH_NAME(BoolValue, "boolValue")
-IDENTIFIER_WITH_NAME(ConvertFromNilLiteral, "convertFromNilLiteral")
+IDENTIFIER_WITH_NAME(NilLiteral, "nilLiteral")
 IDENTIFIER_WITH_NAME(ConvertFromIntegerLiteral, "convertFromIntegerLiteral")
 IDENTIFIER_WITH_NAME(ConvertFromBuiltinIntegerLiteral,
                      "_convertFromBuiltinIntegerLiteral")

lib/ClangImporter/ImportDecl.cpp

@@ -564,58 +564,71 @@ static void makeOptionSetAllZerosProperty(StructDecl *optionSetDecl,
 // Build the NilLiteralConvertible conformance:
 //
 // extension NSSomeOptionSet : NilLiteralConvertible {
-//  static func convertFromNilLiteral() -> S {
+//  init(nilLiteral: ())
-//    return S()
+//    self = S()
 //  }
 // }
-static FuncDecl *makeNilLiteralConformance(StructDecl *optionSetDecl,
+static ConstructorDecl *makeNilLiteralConformance(StructDecl *optionSetDecl,
-                                           ValueDecl *valueDecl) {
+                                                  ValueDecl *valueDecl) {
   auto &C = optionSetDecl->getASTContext();
   auto optionSetType = optionSetDecl->getDeclaredTypeInContext();
   
-  VarDecl *selfDecl = createSelfDecl(optionSetDecl, true);
+  VarDecl *selfDecl = createSelfDecl(optionSetDecl, /*staticMethod=*/false);
   Pattern *selfParam = createTypedNamedPattern(selfDecl);
-  Pattern *methodParam = TuplePattern::create(C, SourceLoc(),{},SourceLoc());
-  methodParam->setType(TupleType::getEmpty(C));
-  Pattern *params[] = {selfParam, methodParam};
 
-  Identifier baseName = C.getIdentifier("convertFromNilLiteral");
+  VarDecl *nilDecl = new (C) ParamDecl(/*isLet=*/true, SourceLoc(),
-  
+                                       C.Id_NilLiteral, SourceLoc(),
-  DeclName name(C, baseName, { });
+                                       Identifier(),
-  auto factoryDecl = FuncDecl::create(C, SourceLoc(), StaticSpellingKind::None,
+                                       TupleType::getEmpty(C),
-                                      SourceLoc(),
+                                       optionSetDecl);
-                                      name,
+  Pattern *nilParam = createTypedNamedPattern(nilDecl);
-                                      SourceLoc(), nullptr, Type(), params,
+  Pattern *methodParam = TuplePattern::create(C, SourceLoc(),
-                                      TypeLoc::withoutLoc(optionSetType),
+                                              { TuplePatternElt(nilParam) },
-                                      optionSetDecl);
+                                              SourceLoc());
-  
+  methodParam->setType(ParenType::get(C, nilParam->getType()));
-  factoryDecl->setStatic();
-  factoryDecl->setImplicit();
-  factoryDecl->setAccessibility(Accessibility::Public);
 
-  Type factoryType = FunctionType::get(TupleType::getEmpty(C), optionSetType);
+  DeclName initName(C, C.Id_init, { C.Id_NilLiteral });
-  factoryType = FunctionType::get(selfDecl->getType(), factoryType);
+  auto initDecl = new (C) ConstructorDecl(initName, SourceLoc(), OTK_None,
-  factoryDecl->setType(factoryType);
+                                          SourceLoc(), selfParam, methodParam,
-  factoryDecl->setBodyResultType(optionSetType);
+                                          nullptr, optionSetDecl);
+  initDecl->setImplicit();
+  initDecl->setAccessibility(Accessibility::Public);
 
+  Type metaType = MetatypeType::get(optionSetType);
+  Type paramType = TupleType::get({ TupleTypeElt(methodParam->getType(),
+                                                 C.Id_NilLiteral) },
+                                  C);
+  Type fnType = FunctionType::get(paramType, optionSetType);
+  Type allocFnType = FunctionType::get(metaType, fnType);
+  Type initFnType = FunctionType::get(optionSetType, fnType);
+  initDecl->setType(allocFnType);
+  initDecl->setInitializerType(initFnType);
+
+  // Form the body of the initializer.
   auto *ctorRef = new (C) DeclRefExpr(ConcreteDeclRef(optionSetDecl),
                                       SourceLoc(), /*implicit*/ true);
   auto *arg = TupleExpr::createEmpty(C, SourceLoc(), SourceLoc(),
                                      /*implicit*/ true);
   auto *ctorCall = new (C) CallExpr(ctorRef, arg, /*implicit*/ true);
-  auto *ctorRet = new (C) ReturnStmt(SourceLoc(), ctorCall, /*implicit*/ true);
+
+  auto selfRef = new (C) DeclRefExpr(selfDecl, SourceLoc(), /*implicit*/ true,
+                                     /*UsesDirectPropertyAccess=*/false,
+                                     selfDecl->getType());
+
+  auto *assign = new (C) AssignExpr(selfRef, SourceLoc(), ctorCall,
+                                    /*implicit*/ true);
   
   auto body = BraceStmt::create(C, SourceLoc(),
-                                ASTNode(ctorRet),
+                                ASTNode(assign),
                                 SourceLoc(),
                                 /*implicit*/ true);
   
-  factoryDecl->setBody(body);
+  initDecl->setBody(body);
   
   // Add as an external definition.
-  C.addedExternalDecl(factoryDecl);
+  C.addedExternalDecl(initDecl);
   
-  return factoryDecl;
+  return initDecl;
 }
 
 // Build the default initializer for an option set.

lib/Sema/CSApply.cpp

@@ -1318,9 +1318,11 @@ namespace {
         if (defaultType->isEqual(type))
           type = defaultType;
       }
-      
+
+      DeclName initName(tc.Context, tc.Context.Id_init,
+                        { tc.Context.Id_NilLiteral });
       return convertLiteral(expr, type, expr->getType(), protocol,
-                            Identifier(), tc.Context.Id_ConvertFromNilLiteral,
+                            Identifier(), initName,
                             nullptr, Identifier(),
                             Identifier(),
                             [] (Type type) -> bool {

stdlib/core/BridgeObjectiveC.swift

@@ -401,8 +401,8 @@ public struct AutoreleasingUnsafeMutablePointer<T /* TODO : class */>
   }
   
   @transparent public
-  static func convertFromNilLiteral() -> AutoreleasingUnsafeMutablePointer {
+  init(nilLiteral: ()) {
-    return AutoreleasingUnsafeMutablePointer(_nilRawPointer)
+    value = _nilRawPointer
   }
   
   @transparent public

stdlib/core/CTypes.swift

@@ -81,7 +81,7 @@ public struct COpaquePointer : Equatable, Hashable, NilLiteralConvertible {
 
   @transparent
   public init() {
-    value = Builtin.inttoptr_Word(0.value)
+    value = _nilRawPointer
   }
 
   @transparent
@@ -133,8 +133,8 @@ public struct COpaquePointer : Equatable, Hashable, NilLiteralConvertible {
   }
   
   @transparent public
-  static func convertFromNilLiteral() -> COpaquePointer {
+  init(nilLiteral: ()) {
-    return COpaquePointer()
+    value = _nilRawPointer
   }
 }
 
@@ -168,8 +168,8 @@ public struct CFunctionPointer<T> : Equatable, Hashable, NilLiteralConvertible {
   }
 
   @transparent public
-  static func convertFromNilLiteral() -> CFunctionPointer {
+  init(nilLiteral: ()) {
-    return CFunctionPointer()
+    value = COpaquePointer()
   }
 }
 

stdlib/core/CompilerProtocols.swift

@@ -204,7 +204,7 @@ public protocol RawOptionSetType : _RawOptionSetType, BitwiseOperationsType,
 /// Conforming to this protocol allows a type to be usable with the 'nil'
 /// literal.
 public protocol NilLiteralConvertible {
-  class func convertFromNilLiteral() -> Self
+  init(nilLiteral: ())
 }
 
 public protocol _BuiltinIntegerLiteralConvertible {

stdlib/core/ImplicitlyUnwrappedOptional.swift

@@ -34,8 +34,8 @@ public enum ImplicitlyUnwrappedOptional<T>
 
   // Make nil work with ImplicitlyUnwrappedOptional
   @transparent public
-  static func convertFromNilLiteral() -> ImplicitlyUnwrappedOptional<T> {
+  init(nilLiteral: ()) {
-    return .None
+    self = .None
   }
 
   /// Haskell's fmap, which was mis-named

stdlib/core/Optional.swift

@@ -37,8 +37,8 @@ public enum Optional<T> : Reflectable, NilLiteralConvertible {
   }
 
   @transparent
-  public static func convertFromNilLiteral() -> Optional<T> {
+  public init(nilLiteral: ()) {
-    return .None
+    self = .None
   }
 }
 
@@ -131,8 +131,7 @@ public func != <T: Equatable> (lhs: T?, rhs: T?) -> Bool {
 // isn't equatable.
 public struct _OptionalNilComparisonType : NilLiteralConvertible {
   @transparent
-  public static func convertFromNilLiteral() -> _OptionalNilComparisonType {
+  public init(nilLiteral: ()) {
-    return _OptionalNilComparisonType()
   }
 }
 @transparent public

stdlib/core/UnsafePointer.swift.gyb

@@ -95,8 +95,8 @@ public struct ${Self}<T>
 
   // Make nil work with ${Self}.
   @transparent public
-  static func convertFromNilLiteral() -> ${Self}<T> {
+  init(nilLiteral: ()) {
-    return .null()
+    self = .null()
   }
 
   @transparent

stdlib/objc/ObjectiveC/ObjectiveC.swift

@@ -121,8 +121,8 @@ public struct Selector : StringLiteralConvertible, NilLiteralConvertible {
   }
   
   @transparent public
-  static func convertFromNilLiteral() -> Selector {
+  init(nilLiteral: ()) {
-    return Selector()
+    ptr = nil
   }
 }
 
@@ -170,8 +170,8 @@ public struct NSZone : NilLiteralConvertible {
   public init() { pointer = nil }
 
   @transparent public
-  static func convertFromNilLiteral() -> NSZone {
+  init(nilLiteral: ()) {
-    return NSZone()
+    pointer = nil
   }
 }
 

test/IDE/Inputs/mock-sdk/Foo.annotated.txt

@@ -39,7 +39,7 @@ struct <loc>FooRuncingOptions</loc> : <ref:Protocol>RawOptionSetType</ref> {
   <decl:Var>static var <loc>EnableMince</loc>: <ref:Struct>FooRuncingOptions</ref> { get }</decl>
   <decl:Var>static var <loc>EnableQuince</loc>: <ref:Struct>FooRuncingOptions</ref> { get }</decl>
   <decl:Var>static var <loc>allZeros</loc>: <ref:Struct>FooRuncingOptions</ref> { get }</decl>
-  <decl:Func>static func <loc>convertFromNilLiteral()</loc> -> <ref:Struct>FooRuncingOptions</ref></decl>
+  <decl:Constructor><loc>init(nilLiteral _: ())</loc></decl>
 }</decl>
 <decl:Struct>struct <loc>FooStruct1</loc> {
   <decl:Var>var <loc>x</loc>: <ref:Struct>Int32</ref></decl>

test/IDE/Inputs/mock-sdk/Foo.printed.recursive.txt

@@ -39,7 +39,7 @@ struct FooRuncingOptions : RawOptionSetType {
   static var EnableMince: FooRuncingOptions { get }
   static var EnableQuince: FooRuncingOptions { get }
   static var allZeros: FooRuncingOptions { get }
-  static func convertFromNilLiteral() -> FooRuncingOptions
+  init(nilLiteral _: ())
 }
 struct FooStruct1 {
   var x: Int32

test/IDE/Inputs/mock-sdk/Foo.printed.txt

@@ -52,7 +52,7 @@ struct FooRuncingOptions : RawOptionSetType {
   static var EnableMince: FooRuncingOptions { get }
   static var EnableQuince: FooRuncingOptions { get } /* But this is quince */
   static var allZeros: FooRuncingOptions { get }
-  static func convertFromNilLiteral() -> FooRuncingOptions
+  init(nilLiteral _: ())
 }
 
 struct FooStruct1 {

test/IDE/print_clang_decls.swift

@@ -79,7 +79,7 @@
 // FOUNDATION-NEXT: {{^}}  static var EnableMince: NSRuncingOptions { get }{{$}}
 // FOUNDATION-NEXT: {{^}}  static var EnableQuince: NSRuncingOptions { get }{{$}}
 // FOUNDATION-NEXT: {{^}}  static var allZeros: NSRuncingOptions { get }{{$}}
-// FOUNDATION-NEXT: {{^}}  static func convertFromNilLiteral() -> NSRuncingOptions{{$}}
+// FOUNDATION-NEXT: {{^}}  init(nilLiteral _: ()){{$}}
 // FOUNDATION-NEXT: {{^}}}{{$}}
 
 // FOUNDATION-LABEL: {{^}}/// Unavailable Global Functions{{$}}

test/Inputs/clang-importer-sdk/swift-modules/ObjectiveC.swift

@@ -62,8 +62,8 @@ public struct NSZone: NilLiteralConvertible {
   public var pointer : COpaquePointer
 
   @transparent public
-  static func convertFromNilLiteral() -> NSZone {
+  init(nilLiteral: ()) {
-    return NSZone(pointer: COpaquePointer())
+    pointer = COpaquePointer()
   }
 }