[AST/Printing] Don't omit empty labels in special names

lib/AST/Identifier.cpp

@@ -184,7 +184,7 @@ llvm::raw_ostream &DeclName::print(llvm::raw_ostream &os,
 }
 
 llvm::raw_ostream &DeclName::printPretty(llvm::raw_ostream &os) const {
-  return print(os, /*skipEmptyArgumentNames=*/true);
+  return print(os, /*skipEmptyArgumentNames=*/!isSpecial());
 }
 
 ObjCSelector::ObjCSelector(ASTContext &ctx, unsigned numArgs,

test/ClangImporter/availability.swift

@@ -54,19 +54,19 @@ func test_unavailable_accessors(_ obj: UnavailableAccessors,
   UnavailableAccessors.setterUnavailableClass = 0 // expected-error {{setter for 'setterUnavailableClass' is unavailable}}
   UnavailableAccessors.setterUnavailableClass += 1 // expected-error {{setter for 'setterUnavailableClass' is unavailable}}
 
-  _ = sub[0] // expected-error {{getter for 'subscript' is unavailable: bad subscript getter}}
-  sub[0] = "" // expected-error {{setter for 'subscript' is unavailable: bad subscript setter}}
-  sub[0] += "" // expected-error {{getter for 'subscript' is unavailable: bad subscript getter}} expected-error {{setter for 'subscript' is unavailable: bad subscript setter}}
+  _ = sub[0] // expected-error {{getter for 'subscript(_:)' is unavailable: bad subscript getter}}
+  sub[0] = "" // expected-error {{setter for 'subscript(_:)' is unavailable: bad subscript setter}}
+  sub[0] += "" // expected-error {{getter for 'subscript(_:)' is unavailable: bad subscript getter}} expected-error {{setter for 'subscript(_:)' is unavailable: bad subscript setter}}
 
-  _ = subGetter[0] // expected-error {{getter for 'subscript' is unavailable: bad subscript getter}}
+  _ = subGetter[0] // expected-error {{getter for 'subscript(_:)' is unavailable: bad subscript getter}}
   subGetter[0] = ""
-  subGetter[0] += "" // expected-error {{getter for 'subscript' is unavailable: bad subscript getter}}
+  subGetter[0] += "" // expected-error {{getter for 'subscript(_:)' is unavailable: bad subscript getter}}
 
   _ = subSetter[0]
-  subSetter[0] = "" // expected-error {{setter for 'subscript' is unavailable: bad subscript setter}}
-  subSetter[0] += "" // expected-error {{setter for 'subscript' is unavailable: bad subscript setter}}
+  subSetter[0] = "" // expected-error {{setter for 'subscript(_:)' is unavailable: bad subscript setter}}
+  subSetter[0] += "" // expected-error {{setter for 'subscript(_:)' is unavailable: bad subscript setter}}
 
-  _ = subReadOnly[0] // expected-error {{getter for 'subscript' is unavailable}}
+  _ = subReadOnly[0] // expected-error {{getter for 'subscript(_:)' is unavailable}}
 }
 
 func test_deprecated(_ s:UnsafeMutablePointer<CChar>, _ obj: AccessorDeprecations,
@@ -100,19 +100,19 @@ func test_deprecated(_ s:UnsafeMutablePointer<CChar>, _ obj: AccessorDeprecation
   AccessorDeprecations.setterDeprecatedClass = 0 // expected-warning {{setter for 'setterDeprecatedClass' is deprecated}}
   AccessorDeprecations.setterDeprecatedClass += 1 // expected-warning {{setter for 'setterDeprecatedClass' is deprecated}}
 
-  _ = sub[0] // expected-warning {{getter for 'subscript' is deprecated: bad subscript getter}}
-  sub[0] = "" // expected-warning {{setter for 'subscript' is deprecated: bad subscript setter}}
-  sub[0] += "" // expected-warning {{getter for 'subscript' is deprecated: bad subscript getter}} expected-warning {{setter for 'subscript' is deprecated: bad subscript setter}}
+  _ = sub[0] // expected-warning {{getter for 'subscript(_:)' is deprecated: bad subscript getter}}
+  sub[0] = "" // expected-warning {{setter for 'subscript(_:)' is deprecated: bad subscript setter}}
+  sub[0] += "" // expected-warning {{getter for 'subscript(_:)' is deprecated: bad subscript getter}} expected-warning {{setter for 'subscript(_:)' is deprecated: bad subscript setter}}
 
-  _ = subGetter[0] // expected-warning {{getter for 'subscript' is deprecated: bad subscript getter}}
+  _ = subGetter[0] // expected-warning {{getter for 'subscript(_:)' is deprecated: bad subscript getter}}
   subGetter[0] = ""
-  subGetter[0] += "" // expected-warning {{getter for 'subscript' is deprecated: bad subscript getter}}
+  subGetter[0] += "" // expected-warning {{getter for 'subscript(_:)' is deprecated: bad subscript getter}}
 
   _ = subSetter[0]
-  subSetter[0] = "" // expected-warning {{setter for 'subscript' is deprecated: bad subscript setter}}
-  subSetter[0] += "" // expected-warning {{setter for 'subscript' is deprecated: bad subscript setter}}
+  subSetter[0] = "" // expected-warning {{setter for 'subscript(_:)' is deprecated: bad subscript setter}}
+  subSetter[0] += "" // expected-warning {{setter for 'subscript(_:)' is deprecated: bad subscript setter}}
 
-  _ = subReadOnly[0] // expected-warning {{getter for 'subscript' is deprecated}}
+  _ = subReadOnly[0] // expected-warning {{getter for 'subscript(_:)' is deprecated}}
 }
 
 func test_NSInvocation(_ x: NSInvocation,         // expected-error {{'NSInvocation' is unavailable}}

test/Compatibility/attr_override.swift

@@ -40,7 +40,7 @@ class A {
   var v9: Int { return 5 } // expected-note{{attempt to override property here}}
   var v10: Int { return 5 } // expected-note{{attempt to override property here}}
 
-  subscript (i: Int) -> String { // expected-note{{potential overridden subscript 'subscript' here}}
+  subscript (i: Int) -> String { // expected-note{{potential overridden subscript 'subscript(_:)' here}}
     get {
       return "hello"
     }
@@ -49,7 +49,7 @@ class A {
     }
   }
 
-  subscript (d: Double) -> String { // expected-note{{overridden declaration is here}} expected-note{{potential overridden subscript 'subscript' here}}
+  subscript (d: Double) -> String { // expected-note{{overridden declaration is here}} expected-note{{potential overridden subscript 'subscript(_:)' here}}
     get {
       return "hello"
     }
@@ -58,11 +58,11 @@ class A {
     }
   }
 
-  subscript (i: Int8) -> A { // expected-note{{potential overridden subscript 'subscript' here}}
+  subscript (i: Int8) -> A { // expected-note{{potential overridden subscript 'subscript(_:)' here}}
     get { return self }
   }
 
-  subscript (i: Int16) -> A { // expected-note{{attempt to override subscript here}} expected-note{{potential overridden subscript 'subscript' here}}
+  subscript (i: Int16) -> A { // expected-note{{attempt to override subscript here}} expected-note{{potential overridden subscript 'subscript(_:)' here}}
     get { return self }
     set { }
   }

test/Compatibility/special_func_name.swift

@@ -14,7 +14,7 @@ struct S12 : P1 { // expected-error {{type 'S12' does not conform to protocol 'P
 }
 
 protocol P2 {
-  init(_: Int) // expected-note {{protocol requires initializer 'init' with type 'Int'; do you want to add a stub?}}
+  init(_: Int) // expected-note {{protocol requires initializer 'init(_:)' with type 'Int'; do you want to add a stub?}}
 }
 
 struct S21 : P2 { // expected-error {{type 'S21' does not conform to protocol 'P2'}}

test/Compatibility/tuple_arguments_4.swift

@@ -513,7 +513,7 @@ do {
 }
 
 struct InitTwo {
-  init(_ x: Int, _ y: Int) {} // expected-note 5 {{'init' declared here}}
+  init(_ x: Int, _ y: Int) {} // expected-note 5 {{'init(_:_:)' declared here}}
 }
 
 struct InitTuple {
@@ -564,7 +564,7 @@ do {
 }
 
 struct SubscriptTwo {
-  subscript(_ x: Int, _ y: Int) -> Int { get { return 0 } set { } } // expected-note 5 {{'subscript' declared here}}
+  subscript(_ x: Int, _ y: Int) -> Int { get { return 0 } set { } } // expected-note 5 {{'subscript(_:_:)' declared here}}
 }
 
 struct SubscriptTuple {
@@ -915,7 +915,7 @@ struct GenericInitLabeled<T> {
 }
 
 struct GenericInitTwo<T> {
-  init(_ x: T, _ y: T) {} // expected-note 10 {{'init' declared here}}
+  init(_ x: T, _ y: T) {} // expected-note 10 {{'init(_:_:)' declared here}}
 }
 
 struct GenericInitTuple<T> {
@@ -1041,7 +1041,7 @@ struct GenericSubscriptLabeled<T> {
 }
 
 struct GenericSubscriptTwo<T> {
-  subscript(_ x: T, _ y: T) -> Int { get { return 0 } set { } } // expected-note 5 {{'subscript' declared here}}
+  subscript(_ x: T, _ y: T) -> Int { get { return 0 } set { } } // expected-note 5 {{'subscript(_:_:)' declared here}}
 }
 
 struct GenericSubscriptLabeledTuple<T> {

test/Constraints/diag_ambiguities.swift

@@ -27,7 +27,7 @@ func g(_ x: Int, _ y: Int) -> () {} // expected-note{{found this candidate}}
 C(g) // expected-error{{ambiguous use of 'g'}}
 
 func h<T>(_ x: T) -> () {}
-C(h) // expected-error{{ambiguous use of 'init'}}
+C(h) // expected-error{{ambiguous use of 'init(_:)'}}
 
 func rdar29691909_callee(_ o: AnyObject?) -> Any? { return o } // expected-note {{found this candidate}}
 func rdar29691909_callee(_ o: AnyObject) -> Any { return o } // expected-note {{found this candidate}}

test/Constraints/diagnostics.swift

@@ -681,7 +681,7 @@ func r23641896() {
   var g = "Hello World"
   g.replaceSubrange(0...2, with: "ce")  // expected-error {{cannot convert value of type 'ClosedRange<Int>' to expected argument type 'Range<String.Index>'}}
 
-  _ = g[12]  // expected-error {{'subscript' is unavailable: cannot subscript String with an Int, see the documentation comment for discussion}}
+  _ = g[12]  // expected-error {{'subscript(_:)' is unavailable: cannot subscript String with an Int, see the documentation comment for discussion}}
 
 }
 
@@ -1199,7 +1199,7 @@ func platypus<T>(a: [T]) {
 func badTypes() {
   let sequence:AnySequence<[Int]> = AnySequence() { AnyIterator() { [3] }}
   let array = [Int](sequence)
-  // expected-error@-1 {{initializer 'init' requires the types 'Int' and '[Int]' be equivalent}}
+  // expected-error@-1 {{initializer 'init(_:)' requires the types 'Int' and '[Int]' be equivalent}}
 }
 
 // rdar://34357545

test/Constraints/generics.swift

@@ -253,7 +253,7 @@ struct V27515965 {
 
 func test(x: S27515965) -> V27515965 {
   return V27515965(x)
-  // expected-error@-1 {{initializer 'init' requires the types 'Any' and 'Float' be equivalent}}
+  // expected-error@-1 {{initializer 'init(_:)' requires the types 'Any' and 'Float' be equivalent}}
 }
 
 protocol BaseProto {}

test/Constraints/lvalues.swift

@@ -233,7 +233,7 @@ r23331567 { $0 += 1 }
 // <rdar://problem/30685195> Compiler crash with invalid assignment
 struct G<T> {
   subscript(x: Int) -> T { get { } nonmutating set { } }
-  // expected-note@-1 {{'subscript' declared here}}
+  // expected-note@-1 {{'subscript(_:)' declared here}}
 }
 
 func wump<T>(to: T, _ body: (G<T>) -> ()) {}

test/Constraints/rdar44569159.swift

@@ -13,6 +13,6 @@ struct A {
 
 func foo(_ v: Double) {
   _ = A()[S(value: v)]
-// expected-error@-1 {{subscript 'subscript' requires that 'Double' conform to 'P'}}
+// expected-error@-1 {{subscript 'subscript(_:)' requires that 'Double' conform to 'P'}}
 // expected-error@-2 {{referencing initializer 'init(value:)' on 'S' requires that 'Double' conform to 'P'}}
 }

test/Constraints/subscript.swift

@@ -68,7 +68,7 @@ extension Int {
   subscript(key: String) -> Double {  get {} }   // expected-note {{found this candidate}}
 }
 
-let _ = 1["1"]  // expected-error {{ambiguous use of 'subscript'}}
+let _ = 1["1"]  // expected-error {{ambiguous use of 'subscript(_:)'}}
 
 let squares = [ 1, 2, 3 ].reduce([:]) { (dict, n) in
   var dict = dict

test/Constraints/tuple.swift

@@ -169,7 +169,7 @@ struct MagicKingdom<K> : Kingdom {
 }
 func magify<T>(_ t: T) -> MagicKingdom<T> { return MagicKingdom() }
 func foo(_ pair: (Int, Int)) -> Victory<(x: Int, y: Int)> {
-  return Victory(magify(pair)) // expected-error {{initializer 'init' requires the types '(x: Int, y: Int)' and '(Int, Int)' be equivalent}}
+  return Victory(magify(pair)) // expected-error {{initializer 'init(_:)' requires the types '(x: Int, y: Int)' and '(Int, Int)' be equivalent}}
 }
 
 

test/Constraints/tuple_arguments.swift

@@ -514,7 +514,7 @@ do {
 }
 
 struct InitTwo {
-  init(_ x: Int, _ y: Int) {} // expected-note 5 {{'init' declared here}}
+  init(_ x: Int, _ y: Int) {} // expected-note 5 {{'init(_:_:)' declared here}}
 }
 
 struct InitTuple {
@@ -565,7 +565,7 @@ do {
 }
 
 struct SubscriptTwo {
-  subscript(_ x: Int, _ y: Int) -> Int { get { return 0 } set { } } // expected-note 5 {{'subscript' declared here}}
+  subscript(_ x: Int, _ y: Int) -> Int { get { return 0 } set { } } // expected-note 5 {{'subscript(_:_:)' declared here}}
 }
 
 struct SubscriptTuple {
@@ -916,7 +916,7 @@ struct GenericInitLabeled<T> {
 }
 
 struct GenericInitTwo<T> {
-  init(_ x: T, _ y: T) {} // expected-note 10 {{'init' declared here}}
+  init(_ x: T, _ y: T) {} // expected-note 10 {{'init(_:_:)' declared here}}
 }
 
 struct GenericInitTuple<T> {
@@ -1042,7 +1042,7 @@ struct GenericSubscriptLabeled<T> {
 }
 
 struct GenericSubscriptTwo<T> {
-  subscript(_ x: T, _ y: T) -> Int { get { return 0 } set { } } // expected-note 5 {{'subscript' declared here}}
+  subscript(_ x: T, _ y: T) -> Int { get { return 0 } set { } } // expected-note 5 {{'subscript(_:_:)' declared here}}
 }
 
 struct GenericSubscriptLabeledTuple<T> {

test/IDE/reconstruct_type_from_mangled_name.swift

@@ -262,7 +262,7 @@ func hasLocalDecls() {
     // CHECK: FAILURE for 'localMethod'
     func localMethod() {}
 
-    // CHECK: FAILURE for 'subscript'
+    // CHECK: FAILURE for 'subscript(_:)'
     subscript(x: Int) { get {} set {} }
 
     // CHECK: decl: FAILURE for ''
@@ -304,7 +304,7 @@ struct HasSubscript {
 // FIXME
 // CHECK: decl: FAILURE	for 'T' usr=s:14swift_ide_test19HasGenericSubscriptV1Txmfp
 struct HasGenericSubscript<T> {
-  // CHECK: subscript<U>(t: T) -> U { get set }	for 'subscript' usr=s:14swift_ide_test19HasGenericSubscriptVyqd__xclui
+  // CHECK: subscript<U>(t: T) -> U { get set }	for 'subscript(_:)' usr=s:14swift_ide_test19HasGenericSubscriptVyqd__xclui
   // FIXME
   // CHECK: decl: FAILURE	for 'U'
   // FIXME

test/NameBinding/accessibility.swift

@@ -54,7 +54,7 @@ _ = Foo() // expected-error {{'Foo' initializer is inaccessible due to 'internal
 // <rdar://problem/27982012> QoI: Poor diagnostic for inaccessible initializer
 struct rdar27982012 {
   var x: Int
-  private init(_ x: Int) { self.x = x } // expected-note {{'init' declared here}}
+  private init(_ x: Int) { self.x = x } // expected-note {{'init(_:)' declared here}}
 }
 
 _ = { rdar27982012($0.0) }((1, 2)) // expected-error {{initializer is inaccessible due to 'private' protection level}}

test/NameBinding/scope_map.swift

@@ -325,7 +325,7 @@ class LazyProperties {
 
 // CHECK-EXPANDED:        TypeDecl {{.*}} StructContainsAbstractStorageDecls [114:1 - 130:1] expanded
 // CHECK-EXPANDED-NEXT: `-TypeOrExtensionBody {{.*}} 'StructContainsAbstractStorageDecls' [114:43 - 130:1] expanded
-// CHECK-EXPANDED-NEXT: {{^}}  |-Accessors {{.*}} scope_map.(file).StructContainsAbstractStorageDecls.subscript@{{.*}}scope_map.swift:115:3 [115:37 - 121:3] expanded
+// CHECK-EXPANDED-NEXT: {{^}}  |-Accessors {{.*}} scope_map.(file).StructContainsAbstractStorageDecls.subscript(_:_:)@{{.*}}scope_map.swift:115:3 [115:37 - 121:3] expanded
 // CHECK-EXPANDED-NEXT: {{^}}  |-AbstractFunctionDecl {{.*}} _ [116:5 - 117:5] expanded
 // CHECK-EXPANDED-NEXT: {{^}}    `-AbstractFunctionParams {{.*}} _ param 0:0 [116:5 - 117:5] expanded
 // CHECK-EXPANDED-NEXT: {{^}}      `-AbstractFunctionParams {{.*}} _ param 1:0 [116:5 - 117:5] expanded
@@ -404,7 +404,7 @@ class LazyProperties {
 // CHECK-EXPANDED-NEXT: {{^}}            `-BraceStmt {{.*}} [167:32 - 167:42] expanded
 // CHECK-EXPANDED-NEXT: {{^}}        `-AbstractFunctionParams {{.*}} defaultArguments(i:j:) param 0:1 [167:48 - 175:1] expanded
 
-// CHECK-EXPANDED: -Accessors {{.*}} scope_map.(file).ProtoWithSubscript.subscript@{{.*}}scope_map.swift:183:3 [183:33 - 183:43] expanded
+// CHECK-EXPANDED: -Accessors {{.*}} scope_map.(file).ProtoWithSubscript.subscript(_:)@{{.*}}scope_map.swift:183:3 [183:33 - 183:43] expanded
 // CHECK-EXPANDED-NEXT:     |-AbstractFunctionDecl {{.*}} _ [183:35 - 183:35] expanded
 // CHECK-EXPANDED-NEXT:       `-AbstractFunctionParams {{.*}} _ param 0:0 [183:35 - 183:35] expanded
 // CHECK-EXPANDED-NEXT:         `-AbstractFunctionParams {{.*}} _ param 1:0 [183:35 - 183:35] expanded

test/Parse/pointer_conversion.swift.gyb

@@ -348,7 +348,7 @@ func takesRawBuffer(_ b: UnsafeRawBufferPointer) {}
 
 // <rdar://problem/29586888> UnsafeRawBufferPointer range subscript is inconsistent with Collection.
 func f29586888(b: UnsafeRawBufferPointer) {
-  takesRawBuffer(b[1..<2]) // expected-error {{'subscript' is unavailable: use 'UnsafeRawBufferPointer(rebasing:)' to convert a slice into a zero-based raw buffer.}}
+  takesRawBuffer(b[1..<2]) // expected-error {{'subscript(_:)' is unavailable: use 'UnsafeRawBufferPointer(rebasing:)' to convert a slice into a zero-based raw buffer.}}
   let slice = b[1..<2]
   takesRawBuffer(slice) // expected-error {{cannot convert value of type 'UnsafeRawBufferPointer.SubSequence' (aka 'Slice<UnsafeRawBufferPointer>') to expected argument type 'UnsafeRawBufferPointer'}}
 }

test/Sema/availability.swift

@@ -41,7 +41,7 @@ class ClassWithUnavailable {
   }
 
   @available(*, unavailable)
-  subscript (i: Int) -> Int { // expected-note{{'subscript' has been explicitly marked unavailable here}}
+  subscript (i: Int) -> Int { // expected-note{{'subscript(_:)' has been explicitly marked unavailable here}}
     return i
   }
 }
@@ -55,7 +55,7 @@ func testInit() {
 }
 
 func testSubscript(cwu: ClassWithUnavailable) {
-  _ = cwu[5] // expected-error{{'subscript' is unavailable}}
+  _ = cwu[5] // expected-error{{'subscript(_:)' is unavailable}}
 }
 
 /* FIXME 'nil == a' fails to type-check with a bogus error message

test/Sema/availability_versions.swift

@@ -253,7 +253,7 @@ class ClassWithUnavailableInitializer {
   convenience init(s: String) {
         // expected-note@-1 {{add @available attribute to enclosing initializer}}
 
-    self.init(5) // expected-error {{'init' is only available on OS X 10.51 or newer}}
+    self.init(5) // expected-error {{'init(_:)' is only available on OS X 10.51 or newer}}
         // expected-note@-1 {{add 'if #available' version check}}
   }
 
@@ -267,12 +267,12 @@ func callUnavailableInitializer() {
       // expected-note@-1 2{{add @available attribute to enclosing global function}}
 
   _ = ClassWithUnavailableInitializer()
-  _ = ClassWithUnavailableInitializer(5) // expected-error {{'init' is only available on OS X 10.51 or newer}}
+  _ = ClassWithUnavailableInitializer(5) // expected-error {{'init(_:)' is only available on OS X 10.51 or newer}}
       // expected-note@-1 {{add 'if #available' version check}}
 
   let i = ClassWithUnavailableInitializer.self 
   _ = i.init()
-  _ = i.init(5) // expected-error {{'init' is only available on OS X 10.51 or newer}}
+  _ = i.init(5) // expected-error {{'init(_:)' is only available on OS X 10.51 or newer}}
       // expected-note@-1 {{add 'if #available' version check}}
 }
 
@@ -290,7 +290,7 @@ class SubOfClassWithUnavailableInitializer : SuperWithWithUnavailableInitializer
   override init(_ val: Int) {
         // expected-note@-1 {{add @available attribute to enclosing initializer}}
 
-    super.init(5) // expected-error {{'init' is only available on OS X 10.51 or newer}}
+    super.init(5) // expected-error {{'init(_:)' is only available on OS X 10.51 or newer}}
         // expected-note@-1 {{add 'if #available' version check}}
   }
 

test/Serialization/builtin.swift

@@ -11,4 +11,4 @@ var a : TheBuiltinInt64
 
 // Check that it really is Builtin.Int64.
 var wrapped = Int64(a) // okay
-var badWrapped = Int32(a) // expected-error{{initializer 'init' requires that 'TheBuiltinInt64' conform to 'BinaryInteger'}}
+var badWrapped = Int32(a) // expected-error{{initializer 'init(_:)' requires that 'TheBuiltinInt64' conform to 'BinaryInteger'}}