Merge pull request swiftlang#19879 from gregomni/8757

[Sema] Omit protocol match diagnosis for constructors with differing names.

Author: gregomni

lib/Sema/TypeCheckProtocol.cpp

@@ -1969,7 +1969,17 @@ static void addOptionalityFixIts(
 /// \brief Diagnose a requirement match, describing what went wrong (or not).
 static void
 diagnoseMatch(ModuleDecl *module, NormalProtocolConformance *conformance,
-              ValueDecl *req, const RequirementMatch &match){
+              ValueDecl *req, const RequirementMatch &match) {
+
+  // If the name doesn't match and that's not the only problem,
+  // it is likely this witness wasn't intended to be a match at all, so omit
+  // diagnosis.
+  if (match.Kind != MatchKind::RenamedMatch &&
+      !match.Witness->getAttrs().hasAttribute<ImplementsAttr>() &&
+      match.Witness->getFullName() &&
+      req->getFullName() != match.Witness->getFullName())
+    return;
+
   // Form a string describing the associated type deductions.
   // FIXME: Determine which associated types matter, and only print those.
   llvm::SmallString<128> withAssocTypes;

test/ClangImporter/objc_parse.swift

@@ -270,7 +270,7 @@ func classAnyObject(_ obj: NSObject) {
 }
 
 // Protocol conformances
-class Wobbler : NSWobbling { // expected-note{{candidate has non-matching type '()'}}
+class Wobbler : NSWobbling {
   @objc func wobble() { }
 
   func returnMyself() -> Self { return self } // expected-error{{non-'@objc' method 'returnMyself()' does not satisfy requirement of '@objc' protocol 'NSWobbling'}}{{none}}
@@ -280,7 +280,7 @@ class Wobbler : NSWobbling { // expected-note{{candidate has non-matching type '
 extension Wobbler : NSMaybeInitWobble { // expected-error{{type 'Wobbler' does not conform to protocol 'NSMaybeInitWobble'}}
 }
 
-@objc class Wobbler2 : NSObject, NSWobbling { // expected-note{{candidate has non-matching type '()'}}
+@objc class Wobbler2 : NSObject, NSWobbling {
   func wobble() { }
   func returnMyself() -> Self { return self }
 }

test/Compatibility/special_func_name.swift

@@ -18,7 +18,6 @@ protocol P2 {
 }
 
 struct S21 : P2 { // expected-error {{type 'S21' does not conform to protocol 'P2'}}
-  // expected-note@-1 {{candidate has non-matching type '()'}}
   static func `init`(_: Int) {}
 }
 

test/Constraints/generic_protocol_witness.swift

@@ -42,7 +42,7 @@ class TooTightConstraints : NeedsGenericMethods { // expected-error{{type 'TooTi
   func oneArgWithConstraint<U : Fungible>(x: U) {} // expected-note{{candidate has non-matching type '<U> (x: U) -> ()'}}
   func oneArgWithConstraints<U : Runcible & Fungible & Ansible>(x: U) {} // expected-note{{candidate has non-matching type '<U> (x: U) -> ()'}}
 
-  func twoArgsOneVar<U : Runcible>(x: U) {} // expected-note{{candidate has non-matching type '<U> (x: U) -> ()'}}
+  func twoArgsOneVar<U : Runcible>(x: U) {}
   func twoArgsTwoVars<U>(x: U, y: U) {} // expected-note{{candidate has non-matching type '<U> (x: U, y: U) -> ()'}}
 }
 func •(_ x: TooTightConstraints, y: Int) {} // expected-note {{candidate has non-matching type '(TooTightConstraints, Int) -> ()'}}

test/decl/func/special_func_name.swift

@@ -18,7 +18,6 @@ protocol P2 {
 }
 
 struct S21 : P2 { // expected-error {{type 'S21' does not conform to protocol 'P2'}}
-  // expected-note@-1 {{candidate has non-matching type '()'}}
   static func `init`(_: Int) {}
 }
 

test/decl/protocol/conforms/failure.swift

@@ -97,7 +97,7 @@ struct P6Conformer : P6 { // expected-error 2 {{does not conform}}
 // expected-error@+1{{type 'A' does not conform to protocol 'RawRepresentable'}}
 struct A: OptionSet {
   let rawValue = 0
-  init() { } // expected-note 2{{candidate has non-matching type '()'}}
+  init() { }
 }
 
 // Type witness cannot have its own generic parameters

test/decl/protocol/conforms/fixit_stub.swift

@@ -11,7 +11,7 @@ protocol Protocol1 {
   subscript(arg1: Int, arg2: Int) -> String { get set } //expected-note{{protocol requires subscript with type '(Int, Int) -> String'; do you want to add a stub?}} {{27-27=\n    func foo(arg1: Int, arg2: String) -> String {\n        <#code#>\n    \}\n\n    func bar() throws -> String {\n        <#code#>\n    \}\n\n    func generic<T>(t: T) {\n        <#code#>\n    \}\n\n    required init(arg: Int) {\n        <#code#>\n    \}\n\n    var baz: Int\n\n    var baz2: Int\n\n    subscript(arg: Int) -> String {\n        <#code#>\n    \}\n\n    subscript(arg1: Int, arg2: Int) -> String {\n        get {\n            <#code#>\n        \}\n        set {\n            <#code#>\n        \}\n    \}\n}}
 }
 
-class Adopter: Protocol1 { // expected-error{{type 'Adopter' does not conform to protocol 'Protocol1'}} expected-note{{candidate has non-matching type '()'}}
+class Adopter: Protocol1 { // expected-error{{type 'Adopter' does not conform to protocol 'Protocol1'}}
 }
 
 
@@ -26,7 +26,7 @@ protocol Protocol2 {
   subscript(arg1: Int, arg2: Int) -> String { get set } //expected-note{{protocol requires subscript with type '(Int, Int) -> String'; do you want to add a stub?}} {{32-32=\n    func foo(arg1: Int, arg2: String) -> String {\n        <#code#>\n    \}\n\n    func bar() throws -> String {\n        <#code#>\n    \}\n\n    var baz: Int {\n        <#code#>\n    \}\n\n    var baz2: Int {\n        get {\n            <#code#>\n        \}\n        set {\n            <#code#>\n        \}\n    \}\n\n    subscript(arg: Int) -> String {\n        <#code#>\n    \}\n\n    subscript(arg1: Int, arg2: Int) -> String {\n        get {\n            <#code#>\n        \}\n        set {\n            <#code#>\n        \}\n    \}\n}}
 }
 
-class Adopter2 {} //  expected-note{{candidate has non-matching type '()'}}
+class Adopter2 {}
 
 extension Adopter2: Protocol2 { // expected-error{{ype 'Adopter2' does not conform to protocol 'Protocol2'}}
 }
@@ -131,19 +131,19 @@ public class Adopter11: ProtocolWithPrivateAccess3, ProtocolWithPrivateAccess4 {
 protocol ProtocolRequiresInit1 {
   init(arg: Int) // expected-note{{protocol requires initializer 'init(arg:)' with type '(arg: Int)'; do you want to add a stub?}} {{48-48=\n    init(arg: Int) {\n        <#code#>\n    \}\n}}
 }
-final class Adopter12 : ProtocolRequiresInit1 {} //expected-error {{type 'Adopter12' does not conform to protocol 'ProtocolRequiresInit1'}} // expected-note{{candidate}}
+final class Adopter12 : ProtocolRequiresInit1 {} //expected-error {{type 'Adopter12' does not conform to protocol 'ProtocolRequiresInit1'}}
 
 protocol ProtocolRequiresInit2 {
   init(arg: Int) // expected-note{{protocol requires initializer 'init(arg:)' with type '(arg: Int)'; do you want to add a stub?}} {{46-46=\n    convenience init(arg: Int) {\n        <#code#>\n    \}\n}}
 }
-final class Adopter13 {} // expected-note{{candidate}}
+final class Adopter13 {}
 extension Adopter13 : ProtocolRequiresInit2 {} //expected-error {{type 'Adopter13' does not conform to protocol 'ProtocolRequiresInit2'}}
 
 protocol ProtocolRequiresInit3 {
   init(arg: Int) // expected-note{{protocol requires initializer 'init(arg:)' with type '(arg: Int)'; do you want to add a stub?}} {{46-46=\n    init(arg: Int) {\n        <#code#>\n    \}\n}}
 }
 
-struct Adopter14 {} // expected-note{{candidate}}
+struct Adopter14 {}
 extension Adopter14 : ProtocolRequiresInit3 {} //expected-error {{type 'Adopter14' does not conform to protocol 'ProtocolRequiresInit3'}}
 
 protocol ProtocolChain1 {

test/decl/protocol/protocols.swift

@@ -77,7 +77,7 @@ class NotPrintableC : CustomStringConvertible, Any {} // expected-error{{type 'N
 enum NotPrintableO : Any, CustomStringConvertible {} // expected-error{{type 'NotPrintableO' does not conform to protocol 'CustomStringConvertible'}}
 
 struct NotFormattedPrintable : FormattedPrintable { // expected-error{{type 'NotFormattedPrintable' does not conform to protocol 'CustomStringConvertible'}}
-  func print(format: TestFormat) {} // expected-note{{candidate has non-matching type '(TestFormat) -> ()'}}
+  func print(format: TestFormat) {} 
 }
 
 // Protocol compositions in inheritance clauses

test/decl/protocol/req/func.swift

@@ -74,7 +74,7 @@ struct X2x : P2 { // expected-error{{type 'X2x' does not conform to protocol 'P2
 // Mismatch in parameter types
 struct X2y : P2 { // expected-error{{type 'X2y' does not conform to protocol 'P2'}}
   typealias Assoc = X1a
-  func f1(x: X1b) { } // expected-note{{candidate has non-matching type '(X1b) -> ()'}}
+  func f1(x: X1b) { }
 }
 
 // Ambiguous deduction
@@ -192,7 +192,7 @@ protocol P6 {
 }
 struct X6 : P6 { // expected-error{{type 'X6' does not conform to protocol 'P6'}}
   func foo(_ x: Missing) { } // expected-error{{use of undeclared type 'Missing'}}
-  func bar() { } // expected-note{{candidate has non-matching type '() -> ()'}}
+  func bar() { }
 }
 
 protocol P6Ownership {

test/decl/protocol/special/coding/enum_coding_key.swift

@@ -41,14 +41,10 @@ enum Int8Key : Int8, CodingKey { // expected-error {{type 'Int8Key' does not con
 
 // Structs conforming to CodingKey should not get implicit derived conformance.
 struct StructKey : CodingKey { // expected-error {{type 'StructKey' does not conform to protocol 'CodingKey'}}
-  // expected-note@-1 {{candidate has non-matching type '()'}}
-  // expected-note@-2 {{candidate has non-matching type '()'}}
 }
 
 // Classes conforming to CodingKey should not get implict derived conformance.
 class ClassKey : CodingKey { //expected-error {{type 'ClassKey' does not conform to protocol 'CodingKey'}}
-  // expected-note@-1 {{candidate has non-matching type '()'}}
-  // expected-note@-2 {{candidate has non-matching type '()'}}
 }
 
 // Types which are valid for CodingKey derived conformance should not get that