Merge pull request #3756 from jckarter/turn-on-anyhashable

Turn on AnyHashable

Author: jckarter

CHANGELOG.md

@@ -3,6 +3,11 @@ Note: This is in reverse chronological order, so newer entries are added to the
 Swift 3.0
 ---------
 
+* [SE-0131](https://github.com/apple/swift-evolution/blob/master/proposals/0131-anyhashable.md):
+  The standard library provides a new type `AnyHashable` for use in heterogenous
+  hashed collections. Untyped `NSDictionary` and `NSSet` APIs from Objective-C
+  now import as `[AnyHashable: Any]` and `Set<AnyHashable>`.
+
 * [SE-0102](https://github.com/apple/swift-evolution/blob/master/proposals/0102-noreturn-bottom-type.md)
   The `@noreturn` attribute on function declarations and function types has been removed,
   in favor of an empty `Never` type:
@@ -18,7 +23,7 @@ Swift 3.0
 * [SE-0116](https://github.com/apple/swift-evolution/blob/master/proposals/0116-id-as-any.md):
   Objective-C APIs using `id` now import into Swift as `Any` instead of as `AnyObject`.
   Similarly, APIs using untyped `NSArray` and `NSDictionary` import as `[Any]` and
-  `[NSObject: Any]`, respectively.
+  `[AnyHashable: Any]`, respectively.
 
 * [SE-0072](https://github.com/apple/swift-evolution/blob/master/proposals/0072-eliminate-implicit-bridging-conversions.md):
   Bridging conversions are no longer implicit. The conversion from a Swift value type to

include/swift/AST/ASTContext.h

@@ -401,6 +401,9 @@ class ASTContext {
   /// Retrieve the declaration of Swift.Dictionary<K, V>.
   NominalTypeDecl *getDictionaryDecl() const;
 
+  /// Retrieve the declaration of Swift.AnyHashable.
+  NominalTypeDecl *getAnyHashableDecl() const;
+
   /// Retrieve the declaration of Swift.Optional or ImplicitlyUnwrappedOptional.
   EnumDecl *getOptionalDecl(OptionalTypeKind kind) const;
 

include/swift/SIL/SILBuilder.h

@@ -424,6 +424,7 @@ class SILBuilder {
   }
 
   LoadInst *createLoad(SILLocation Loc, SILValue LV) {
+    assert(LV->getType().isLoadable(F.getModule()));
     return insert(new (F.getModule())
                       LoadInst(getSILDebugLocation(Loc), LV));
   }

lib/AST/ASTContext.cpp

@@ -138,6 +138,9 @@ struct ASTContext::Implementation {
   /// The declaration of Swift.Dictionary<T>.
   NominalTypeDecl *DictionaryDecl = nullptr;
 
+  /// The declaration of Swift.AnyHashable.
+  NominalTypeDecl *AnyHashableDecl = nullptr;
+
   /// The declaration of Swift.Optional<T>.
   EnumDecl *OptionalDecl = nullptr;
 
@@ -637,6 +640,12 @@ NominalTypeDecl *ASTContext::getDictionaryDecl() const {
   return Impl.DictionaryDecl;
 }
 
+NominalTypeDecl *ASTContext::getAnyHashableDecl() const {
+  if (!Impl.AnyHashableDecl)
+    Impl.AnyHashableDecl = findStdlibType(*this, "AnyHashable", 0);
+  return Impl.AnyHashableDecl;
+}
+
 EnumDecl *ASTContext::getOptionalDecl(OptionalTypeKind kind) const {
   switch (kind) {
   case OTK_None:
@@ -4011,6 +4020,7 @@ bool ASTContext::isStandardLibraryTypeBridgedInFoundation(
           nominal == getSetDecl() ||
           nominal == getStringDecl() ||
           nominal == getErrorDecl() ||
+          nominal == getAnyHashableDecl() ||
           // Weird one-off case where CGFloat is bridged to NSNumber.
           nominal->getName() == Id_CGFloat);
 }

lib/ClangImporter/ImportType.cpp

@@ -919,12 +919,18 @@ namespace {
               return Type();
 
             // The first type argument for Dictionary or Set needs
-            // to be NSObject-bound.
+            // to be Hashable. Everything that inherits NSObject has a
+            // -hash code in ObjC, but if something isn't NSObject, fall back
+            // to AnyHashable as a key type.
             if (unboundDecl == Impl.SwiftContext.getDictionaryDecl() ||
                 unboundDecl == Impl.SwiftContext.getSetDecl()) {
               auto &keyType = importedTypeArgs[0];
-              if (!Impl.matchesNSObjectBound(keyType))
-                keyType = Impl.getNSObjectType();
+              if (!Impl.matchesNSObjectBound(keyType)) {
+                if (auto anyHashable = Impl.SwiftContext.getAnyHashableDecl())
+                  keyType = anyHashable->getDeclaredType();
+                else
+                  keyType = Type();
+              }
             }
 
             // Form the specialized type.
@@ -2635,6 +2641,7 @@ bool ClangImporter::Implementation::matchesNSObjectBound(Type type) {
     return true;
 
   // Struct or enum type must have been bridged.
+  // TODO: Check that the bridged type is Hashable?
   if (type->getStructOrBoundGenericStruct() ||
       type->getEnumOrBoundGenericEnum())
     return true;

lib/ClangImporter/ImporterImpl.h

@@ -1160,7 +1160,7 @@ class LLVM_LIBRARY_VISIBILITY ClangImporter::Implementation
   Type getCFStringRefType();
 
   /// \brief Determines whether the given type matches an implicit type
-  /// bound of "NSObject", which is used to validate NSDictionary/NSSet.
+  /// bound of "Hashable", which is used to validate NSDictionary/NSSet.
   bool matchesNSObjectBound(Type type);
 
   /// \brief Look up and attempt to import a Clang declaration with

lib/SIL/SILModule.cpp

@@ -316,7 +316,8 @@ SILFunction *SILModule::getOrCreateFunction(SILLocation loc,
 
   if (auto fn = lookUpFunction(name)) {
     assert(fn->getLoweredFunctionType() == constantType);
-    assert(fn->getLinkage() == linkage);
+    assert(fn->getLinkage() == constant.getLinkage(ForDefinition)
+           || fn->getLinkage() == constant.getLinkage(NotForDefinition));
     if (forDefinition) {
       // In all the cases where getConstantLinkage returns something
       // different for ForDefinition, it returns an available-externally

lib/SILOptimizer/Utils/Local.cpp

@@ -1426,6 +1426,11 @@ optimizeBridgedObjCToSwiftCast(SILInstruction *Inst,
   assert(Src->getType().isAddress() && "Source should have an address type");
   assert(Dest->getType().isAddress() && "Source should have an address type");
 
+  if (!Src->getType().isLoadable(M) || !Dest->getType().isLoadable(M)) {
+    // TODO: Handle address only types.
+    return nullptr;
+  }
+
   if (SILBridgedTy != Src->getType()) {
     // Check if we can simplify a cast into:
     // - ObjCTy to _ObjectiveCBridgeable._ObjectiveCType.
@@ -1603,6 +1608,11 @@ optimizeBridgedSwiftToObjCCast(SILInstruction *Inst,
 
   auto &M = Inst->getModule();
   auto Loc = Inst->getLoc();
+  
+  if (!Src->getType().isLoadable(M) || !Dest->getType().isLoadable(M)) {
+    // TODO: Handle address-only types.
+    return nullptr;
+  }
 
   // Find the _BridgedToObjectiveC protocol.
   auto BridgedProto =

lib/Sema/TypeCheckType.cpp

@@ -2370,9 +2370,11 @@ Type TypeResolver::resolveTupleType(TupleTypeRepr *repr,
       complained = true;
     } 
 
-    // Single-element labeled tuples are not permitted, either.
-    if (elements.size() == 1 && elements[0].hasName() &&
-        !(options & TR_EnumCase)) {
+    // Single-element labeled tuples are not permitted outside of declarations
+    // or SIL, either.
+    if (elements.size() == 1 && elements[0].hasName()
+        && !(options & TR_SILType)
+        && !(options & TR_EnumCase)) {
       if (!complained) {
         auto named = cast<NamedTypeRepr>(repr->getElement(0));
         TC.diagnose(repr->getElement(0)->getStartLoc(),

stdlib/public/SDK/CoreImage/CoreImage.swift

@@ -50,9 +50,9 @@ extension CIFilter {
 extension CISampler {
   // - (id)initWithImage:(CIImage *)im keysAndValues:key0, ...;
   convenience init(im: CIImage, elements: (String, Any)...) {
-    var dict: [NSObject : Any] = [:]
+    var dict: [AnyHashable : Any] = [:]
     for (key, value) in elements {
-      dict[key as NSObject] = value
+      dict[key] = value
     }
 
     // @objc(initWithImage:options:)

stdlib/public/SDK/Foundation/Foundation.swift

@@ -72,6 +72,9 @@ extension NSString : ExpressibleByStringLiteral {
 }
 
 extension NSString : _HasCustomAnyHashableRepresentation {
+  // Must be @nonobjc to prevent infinite recursion trying to bridge
+  // AnyHashable to NSObject.
+  @nonobjc
   public func _toCustomAnyHashable() -> AnyHashable? {
     // Consistently use Swift equality and hashing semantics for all strings.
     return AnyHashable(self as String)
@@ -429,6 +432,9 @@ extension NSNumber
 }
 
 extension NSNumber : _HasCustomAnyHashableRepresentation {
+  // Must be @nonobjc to prevent infinite recursion trying to bridge
+  // AnyHashable to NSObject.
+  @nonobjc
   public func _toCustomAnyHashable() -> AnyHashable? {
     guard let kind = _SwiftTypePreservingNSNumberTag(
       rawValue: Int(_swift_Foundation_TypePreservingNSNumberGetKind(self))
@@ -1231,7 +1237,8 @@ extension NSSet {
   ///   receiver.
   @objc(_swiftInitWithSet_NSSet:)
   public convenience init(set anSet: NSSet) {
-    self.init(set: anSet as Set)
+    // FIXME: This is a bit weird. Maybe there's a better way?
+    self.init(set: anSet as Set<NSObject> as Set<AnyHashable>)
   }
 }
 
@@ -1244,7 +1251,9 @@ extension NSDictionary {
   ///   found in `otherDictionary`.
   @objc(_swiftInitWithDictionary_NSDictionary:)
   public convenience init(dictionary otherDictionary: NSDictionary) {
-    self.init(dictionary: otherDictionary as Dictionary)
+    // FIXME: This is a bit weird. Maybe there's a better way?
+    self.init(dictionary: otherDictionary as [NSObject: AnyObject]
+                                          as [AnyHashable: Any])
   }
 }
 
@@ -1495,3 +1504,39 @@ typealias KeyedUnarchiver = NSKeyedUnarchiver
 @available(*, deprecated, renamed:"NSKeyedArchiver", message: "Please use NSKeyedArchiver")
 typealias KeyedArchiver = NSKeyedArchiver
 
+//===----------------------------------------------------------------------===//
+// AnyHashable
+//===----------------------------------------------------------------------===//
+
+extension AnyHashable : _ObjectiveCBridgeable {
+  public func _bridgeToObjectiveC() -> NSObject {
+    // This is unprincipled, but pretty much any object we'll encounter in
+    // Swift is NSObject-conforming enough to have -hash and -isEqual:.
+    return unsafeBitCast(base as AnyObject, to: NSObject.self)
+  }
+
+  public static func _forceBridgeFromObjectiveC(
+    _ x: NSObject,
+    result: inout AnyHashable?
+  ) {
+    result = AnyHashable(x)
+  }
+
+  public static func _conditionallyBridgeFromObjectiveC(
+    _ x: NSObject,
+    result: inout AnyHashable?
+  ) -> Bool {
+    self._forceBridgeFromObjectiveC(x, result: &result)
+    return result != nil
+  }
+
+  public static func _unconditionallyBridgeFromObjectiveC(
+    _ source: NSObject?
+  ) -> AnyHashable {
+    // `nil` has historically been used as a stand-in for an empty
+    // string; map it to an empty string.
+    if _slowPath(source == nil) { return AnyHashable(String()) }
+    return AnyHashable(source!)
+  }
+}
+

stdlib/public/SDK/Foundation/NSError.swift

@@ -389,11 +389,11 @@ public protocol _BridgedStoredNSError :
 }
 
 /// TODO: Better way to do this?
-internal func _stringDictToNSObjectDict(_ input: [String : Any])
-    -> [NSObject : Any] {
-  var result: [NSObject : Any] = [:]
+internal func _stringDictToAnyHashableDict(_ input: [String : Any])
+    -> [AnyHashable : Any] {
+  var result: [AnyHashable : Any] = [:]
   for (k, v) in input {
-    result[k as NSString] = v
+    result[k] = v
   }
   return result
 }
@@ -411,7 +411,7 @@ public extension _BridgedStoredNSError
   public init(_ code: Code, userInfo: [String : Any] = [:]) {
     self.init(_nsError: NSError(domain: Self._nsErrorDomain,
                                 code: numericCast(code.rawValue),
-                                userInfo: _stringDictToNSObjectDict(userInfo)))
+                                userInfo: _stringDictToAnyHashableDict(userInfo)))
   }
 
   /// The user-info dictionary for an error that was bridged from
@@ -432,7 +432,7 @@ public extension _BridgedStoredNSError
   public init(_ code: Code, userInfo: [String : Any] = [:]) {
     self.init(_nsError: NSError(domain: Self._nsErrorDomain,
                                 code: numericCast(code.rawValue),
-                                userInfo: _stringDictToNSObjectDict(userInfo)))
+                                userInfo: _stringDictToAnyHashableDict(userInfo)))
   }
 }
 
@@ -461,7 +461,7 @@ public extension _BridgedStoredNSError {
   var errorUserInfo: [String : Any] {
     var result: [String : Any] = [:]
     for (key, value) in _nsError.userInfo {
-      guard let stringKey = key as? String else { continue }
+      guard let stringKey = key.base as? String else { continue }
       result[stringKey] = value
     }
     return result
@@ -528,7 +528,7 @@ public struct CocoaError : _BridgedStoredNSError {
 }
 
 public extension CocoaError {
-  private var _nsUserInfo: [NSObject : Any] {
+  private var _nsUserInfo: [AnyHashable : Any] {
     return (self as NSError).userInfo
   }
 
@@ -1329,7 +1329,7 @@ public struct URLError : _BridgedStoredNSError {
 }
 
 public extension URLError {
-  private var _nsUserInfo: [NSObject : Any] {
+  private var _nsUserInfo: [AnyHashable : Any] {
     return (self as NSError).userInfo
   }
 

stdlib/public/SDK/Foundation/NSStringAPI.swift

@@ -1180,7 +1180,8 @@ extension String {
   /// values found in the `String`.
   public
   func propertyListFromStringsFileFormat() -> [String : String] {
-    return _ns.propertyListFromStringsFileFormat() as! [String : String]
+    return _ns.propertyListFromStringsFileFormat()! as [NSObject : AnyObject]
+      as! [String : String]
   }
 
   // - (NSRange)rangeOfCharacterFromSet:(NSCharacterSet *)aSet

test/1_stdlib/ErrorBridged.swift

@@ -97,10 +97,10 @@ ErrorBridgingTests.test("NSError-to-enum bridging") {
     let ns = NSError(domain: NSCocoaErrorDomain,
                      code: NSFileNoSuchFileError,
                      userInfo: [
-                       NSFilePathErrorKey as NSObject : "/dev/null",
-                       NSStringEncodingErrorKey as NSObject: /*ASCII=*/1,
-                       NSUnderlyingErrorKey as NSObject: underlyingError,
-                       NSURLErrorKey as NSObject: testURL
+                       AnyHashable(NSFilePathErrorKey): "/dev/null",
+                       AnyHashable(NSStringEncodingErrorKey): /*ASCII=*/1,
+                       AnyHashable(NSUnderlyingErrorKey): underlyingError,
+                       AnyHashable(NSURLErrorKey): testURL
                      ])
 
     objc_setAssociatedObject(ns, &CanaryHandle, NoisyError(),
@@ -143,7 +143,7 @@ ErrorBridgingTests.test("NSError-to-enum bridging") {
     // URLError domain
     let nsURL = NSError(domain: NSURLErrorDomain,
                         code: NSURLErrorBadURL,
-                        userInfo: [NSURLErrorFailingURLErrorKey as NSObject : testURL])
+                        userInfo: [AnyHashable(NSURLErrorFailingURLErrorKey): testURL])
     let eURL: Error = nsURL
     let isBadURLError: Bool
     switch eURL {
@@ -162,7 +162,7 @@ ErrorBridgingTests.test("NSError-to-enum bridging") {
     // CoreLocation error domain
     let nsCL = NSError(domain: kCLErrorDomain,
                        code: CLError.headingFailure.rawValue,
-                       userInfo: [NSURLErrorKey as NSObject: testURL])
+                       userInfo: [AnyHashable(NSURLErrorKey): testURL])
     let eCL: Error = nsCL
     let isHeadingFailure: Bool
     switch eCL {
@@ -318,7 +318,7 @@ class SomeNSErrorSubclass: NSError {}
 ErrorBridgingTests.test("Thrown NSError identity is preserved") {
   do {
     let e = NSError(domain: "ClericalError", code: 219,
-                    userInfo: ["yeah": "yeah"])
+                    userInfo: [AnyHashable("yeah"): "yeah"])
     do {
       throw e
     } catch let e2 as NSError {
@@ -331,7 +331,7 @@ ErrorBridgingTests.test("Thrown NSError identity is preserved") {
 
   do {
     let f = SomeNSErrorSubclass(domain: "ClericalError", code: 219,
-                                userInfo: ["yeah": "yeah"])
+                                userInfo: [AnyHashable("yeah"): "yeah"])
     do {
       throw f
     } catch let f2 as NSError {

test/1_stdlib/NSEnumeratorAPI.swift

@@ -18,7 +18,7 @@ NSEnumeratorAPI.test("Sequence") {
 NSEnumeratorAPI.test("keyEnumerator") {
   let result = [1 as NSNumber: "one", 2 as NSNumber: "two"]
   expectEqualsUnordered(
-    [1, 2], NSDictionary(dictionary: result).keyEnumerator()) {
+    [1, 2], NSDictionary(dictionary: result as [AnyHashable: Any]).keyEnumerator()) {
       switch ($0 as! Int, $1 as! Int) {
       case let (x, y) where x == y: return .eq
       case let (x, y) where x < y: return .lt