test/decl/protocol/req/func.swift - third_party/swift - Git at Google

 // RUN: %target-typecheck-verify-swift -enable-objc-interop

 // Test function requirements within protocols, as well as conformance to
 // said protocols.

 // Simple function
 protocol P1 {
   func f0()
 }

 // Simple match
 struct X1a : P1 {
   func f0() {}
 }

 // Simple match selecting among two overloads.
 struct X1b : P1 {
   func f0() -> Int {}
   func f0() {}
 }

 // Function with an associated type
 protocol P2 {
   associatedtype Assoc : P1 // expected-note{{ambiguous inference of associated type 'Assoc': 'X1a' vs. 'X1b'}}
   // expected-note@-1{{protocol requires nested type 'Assoc'}}
   func f1(_ x: Assoc) // expected-note{{protocol requires function 'f1' with type '(X2w.Assoc) -> ()'}} expected-note{{protocol requires function 'f1' with type '(X2y.Assoc) -> ()'}}
 }

 // Exact match.
 struct X2a : P2 {
   typealias Assoc = X1a

   func f1(_ x: X1a) {}
 }

 // Select among overloads.
 struct X2d : P2 {
   typealias Assoc = X1a

   func f1(_ x: Int) { }
   func f1(_ x: X1a) { }
 }

 struct X2e : P2 {
   typealias Assoc = X1a

   func f1(_ x: X1b) { }
   func f1(_ x: X1a) { }
 }

 // Select among overloads distinguished by name.
 struct X2f : P2 {
   typealias Assoc = X1a
   func f1(y: X1a) { }
   func f1(_ x: X1a) { }
 }

 // Infer associated type from function parameter
 struct X2g : P2 {
   func f1(_ x: X1a) { }
 }

 // Static/non-static mismatch.
 struct X2w : P2 { // expected-error{{type 'X2w' does not conform to protocol 'P2'}}
   typealias Assoc = X1a
   static func f1(_ x: X1a) { } // expected-note{{candidate operates on a type, not an instance as required}}
 }

 // Deduction of type that doesn't meet requirements
 struct X2x : P2 { // expected-error{{type 'X2x' does not conform to protocol 'P2'}}
   func f1(x: Int) { }
 }

 // Mismatch in parameter types
 struct X2y : P2 { // expected-error{{type 'X2y' does not conform to protocol 'P2'}}
   typealias Assoc = X1a
   func f1(x: X1b) { }
 }

 // Ambiguous deduction
 struct X2z : P2 { // expected-error{{type 'X2z' does not conform to protocol 'P2'}}
   func f1(_ x: X1a) { } // expected-note{{matching requirement 'f1' to this declaration inferred associated type to 'X1a'}}
   func f1(_ x: X1b) { } // expected-note{{matching requirement 'f1' to this declaration inferred associated type to 'X1b'}}
 }

 // Protocol with prefix unary function
 prefix operator ~~

 protocol P3 {
   associatedtype Assoc : P1
   static prefix func ~~(_: Self) -> Assoc // expected-note{{protocol requires function '~~' with type '(X3z) -> X3z.Assoc'}}
 }

 // Global operator match
 struct X3a : P3 {
   typealias Assoc = X1a
 }

 prefix func ~~(_: X3a) -> X1a {}

 // FIXME: Add example with overloaded prefix/postfix

 // Prefix/postfix mismatch.
 struct X3z : P3 { // expected-error{{type 'X3z' does not conform to protocol 'P3'}}
   typealias Assoc = X1a
 }

 postfix func ~~(_: X3z) -> X1a {} // expected-note{{candidate is postfix, not prefix as required}}

 // Protocol with postfix unary function
 postfix operator ~~
 protocol P4 {
   associatedtype Assoc : P1
   static postfix func ~~ (_: Self) -> Assoc // expected-note{{protocol requires function '~~' with type '(X4z) -> X4z.Assoc'}}
 }

 // Global operator match
 struct X4a : P4 {
   typealias Assoc = X1a
 }

 postfix func ~~(_: X4a) -> X1a {}

 // Prefix/postfix mismatch.
 struct X4z : P4 { // expected-error{{type 'X4z' does not conform to protocol 'P4'}}
   typealias Assoc = X1a
 }

 prefix func ~~(_: X4z) -> X1a {} // expected-note{{candidate is prefix, not postfix as required}}

 // Objective-C protocol
 @objc protocol P5 {
   func f2(_ x: Int, withInt a: Int)
   func f2(_ x: Int, withOtherInt a: Int)
 }

 // Exact match.
 class X5a : P5 {
   @objc func f2(_ x: Int, withInt a: Int) {}
   @objc func f2(_ x: Int, withOtherInt a: Int) {}
 }

 // Body parameter names can vary.
 class X5b : P5 {
   @objc func f2(_ y: Int, withInt a: Int) {}
   @objc func f2(_ y: Int, withOtherInt a: Int) {}
 }

 class X5c : P5 {
   @objc func f2(_ y: Int, withInt b: Int) {}
   @objc func f2(_ y: Int, withOtherInt b: Int) {}
 }

 // Names need to match up for an Objective-C protocol as well.
 class X5d : P5 {
   @objc(f2WithY:withInt:) func f2(_ y: Int, withInt a: Int) {} // expected-error {{Objective-C method 'f2WithY:withInt:' provided by method 'f2(_:withInt:)' does not match the requirement's selector ('f2:withInt:')}}
   @objc(f2WithY:withOtherValue:) func f2(_ y: Int, withOtherInt a: Int) {} // expected-error{{Objective-C method 'f2WithY:withOtherValue:' provided by method 'f2(_:withOtherInt:)' does not match the requirement's selector ('f2:withOtherInt:')}}
 }

 // Distinguish names within tuple arguments.
 typealias T0 = (x: Int, y: String)
 typealias T1 = (xx: Int, y: String)

 func f(_ args: T0) {
 }

 func f(_ args: T1) {
 }

 f(T0(1, "Hi"))

 infix operator ~>> : MaxPrecedence
 precedencegroup MaxPrecedence { higherThan: BitwiseShiftPrecedence }

 func ~>> (x: Int, args: T0) {}
 func ~>> (x: Int, args: T1) {}

 3~>>T0(1, "Hi")
 3~>>T1(2, "Hi")

 protocol Crankable {
   static func ~>> (x: Self, args: T0)
   static func ~>> (x: Self, args: T1)
 }

 extension Int : Crankable {}

 // Invalid witnesses.
 protocol P6 {
   func foo(_ x: Int)
   func bar(x: Int) // expected-note{{protocol requires function 'bar(x:)' with type '(Int) -> ()'}}
 }
 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() { }
 }

 protocol P6Ownership {
   func thunk__shared(_ x: __shared Int)
   func mismatch__shared(_ x: Int)
   func mismatch__owned(x: Int)
   func thunk__owned__owned(x: __owned Int)

   __consuming func inherits__consuming(x: Int)
   func mismatch__consuming(x: Int)
   __consuming func mismatch__consuming_mutating(x: Int) // expected-note {{protocol requires function 'mismatch__consuming_mutating(x:)' with type '(Int) -> ()'}}
   mutating func mismatch__mutating_consuming(x: Int)
 }
 struct X6Ownership : P6Ownership { // expected-error{{type 'X6Ownership' does not conform to protocol 'P6Ownership'}}
   func thunk__shared(_ x: Int) { } // OK
   func mismatch__shared(_ x: __shared Int) { } // OK
   func mismatch__owned(x: __owned Int) { } // OK
   func thunk__owned__owned(x: Int) { } // OK

   func inherits__consuming(x: Int) { } // OK
   __consuming func mismatch__consuming(x: Int) { } // OK
   mutating func mismatch__consuming_mutating(x: Int) { } // expected-note {{candidate is marked 'mutating' but protocol does not allow it}}
   __consuming func mismatch__mutating_consuming(x: Int) { } // OK - '__consuming' acts as a counterpart to 'nonmutating'
 }

 protocol P7 {
   func foo(_ x: Blarg) // expected-error{{use of undeclared type 'Blarg'}}
 }

 struct X7 : P7 { }

 // Selecting the most specialized witness.
 prefix operator %%%

 protocol P8 {
   func foo()
 }

 prefix func %%% <T : P8>(x: T) -> T { }

 protocol P9 : P8 {
   static prefix func %%% (x: Self) -> Self
 }

 struct X9 : P9 {
   func foo() {}
 }

 prefix func %%%(x: X9) -> X9 { }

 protocol P10 {
   associatedtype Assoc
   func bar(_ x: Assoc)
 }

 struct X10 : P10 {
   typealias Assoc = Int
   func bar(_ x: Int) { }
   func bar<T>(_ x: T) { }
 }

 protocol P11 {
   static func ==(x: Self, y: Self) -> Bool
 }

 protocol P12 {
   associatedtype Index : P1 // expected-note{{unable to infer associated type 'Index' for protocol 'P12'}}
   func getIndex() -> Index
 }

 struct XIndexType : P11 { }

 struct X12 : P12 { // expected-error{{type 'X12' does not conform to protocol 'P12'}}
   func getIndex() -> XIndexType { return XIndexType() } // expected-note{{candidate would match and infer 'Index' = 'XIndexType' if 'XIndexType' conformed to 'P1'}}
 }

 func ==(x: X12.Index, y: X12.Index) -> Bool { return true }

 protocol P13 {}
 protocol P14 {
   static prefix func %%%(_: Self.Type)
 }
 prefix func %%%<P: P13>(_: P.Type) { }
 struct X13: P14, P13 { }
	// RUN: %target-typecheck-verify-swift -enable-objc-interop

	// Test function requirements within protocols, as well as conformance to
	// said protocols.

	// Simple function
	protocol P1 {
	func f0()
	}

	// Simple match
	struct X1a : P1 {
	func f0() {}
	}

	// Simple match selecting among two overloads.
	struct X1b : P1 {
	func f0() -> Int {}
	func f0() {}
	}

	// Function with an associated type
	protocol P2 {
	associatedtype Assoc : P1 // expected-note{{ambiguous inference of associated type 'Assoc': 'X1a' vs. 'X1b'}}
	// expected-note@-1{{protocol requires nested type 'Assoc'}}
	func f1(_ x: Assoc) // expected-note{{protocol requires function 'f1' with type '(X2w.Assoc) -> ()'}} expected-note{{protocol requires function 'f1' with type '(X2y.Assoc) -> ()'}}
	}

	// Exact match.
	struct X2a : P2 {
	typealias Assoc = X1a

	func f1(_ x: X1a) {}
	}

	// Select among overloads.
	struct X2d : P2 {
	typealias Assoc = X1a

	func f1(_ x: Int) { }
	func f1(_ x: X1a) { }
	}

	struct X2e : P2 {
	typealias Assoc = X1a

	func f1(_ x: X1b) { }
	func f1(_ x: X1a) { }
	}

	// Select among overloads distinguished by name.
	struct X2f : P2 {
	typealias Assoc = X1a
	func f1(y: X1a) { }
	func f1(_ x: X1a) { }
	}

	// Infer associated type from function parameter
	struct X2g : P2 {
	func f1(_ x: X1a) { }
	}

	// Static/non-static mismatch.
	struct X2w : P2 { // expected-error{{type 'X2w' does not conform to protocol 'P2'}}
	typealias Assoc = X1a
	static func f1(_ x: X1a) { } // expected-note{{candidate operates on a type, not an instance as required}}
	}

	// Deduction of type that doesn't meet requirements
	struct X2x : P2 { // expected-error{{type 'X2x' does not conform to protocol 'P2'}}
	func f1(x: Int) { }
	}

	// Mismatch in parameter types
	struct X2y : P2 { // expected-error{{type 'X2y' does not conform to protocol 'P2'}}
	typealias Assoc = X1a
	func f1(x: X1b) { }
	}

	// Ambiguous deduction
	struct X2z : P2 { // expected-error{{type 'X2z' does not conform to protocol 'P2'}}
	func f1(_ x: X1a) { } // expected-note{{matching requirement 'f1' to this declaration inferred associated type to 'X1a'}}
	func f1(_ x: X1b) { } // expected-note{{matching requirement 'f1' to this declaration inferred associated type to 'X1b'}}
	}

	// Protocol with prefix unary function
	prefix operator ~~

	protocol P3 {
	associatedtype Assoc : P1
	static prefix func ~~(_: Self) -> Assoc // expected-note{{protocol requires function '~~' with type '(X3z) -> X3z.Assoc'}}
	}

	// Global operator match
	struct X3a : P3 {
	typealias Assoc = X1a
	}

	prefix func ~~(_: X3a) -> X1a {}

	// FIXME: Add example with overloaded prefix/postfix

	// Prefix/postfix mismatch.
	struct X3z : P3 { // expected-error{{type 'X3z' does not conform to protocol 'P3'}}
	typealias Assoc = X1a
	}

	postfix func ~~(_: X3z) -> X1a {} // expected-note{{candidate is postfix, not prefix as required}}

	// Protocol with postfix unary function
	postfix operator ~~
	protocol P4 {
	associatedtype Assoc : P1
	static postfix func ~~ (_: Self) -> Assoc // expected-note{{protocol requires function '~~' with type '(X4z) -> X4z.Assoc'}}
	}

	// Global operator match
	struct X4a : P4 {
	typealias Assoc = X1a
	}

	postfix func ~~(_: X4a) -> X1a {}

	// Prefix/postfix mismatch.
	struct X4z : P4 { // expected-error{{type 'X4z' does not conform to protocol 'P4'}}
	typealias Assoc = X1a
	}

	prefix func ~~(_: X4z) -> X1a {} // expected-note{{candidate is prefix, not postfix as required}}

	// Objective-C protocol
	@objc protocol P5 {
	func f2(_ x: Int, withInt a: Int)
	func f2(_ x: Int, withOtherInt a: Int)
	}

	// Exact match.
	class X5a : P5 {
	@objc func f2(_ x: Int, withInt a: Int) {}
	@objc func f2(_ x: Int, withOtherInt a: Int) {}
	}

	// Body parameter names can vary.
	class X5b : P5 {
	@objc func f2(_ y: Int, withInt a: Int) {}
	@objc func f2(_ y: Int, withOtherInt a: Int) {}
	}

	class X5c : P5 {
	@objc func f2(_ y: Int, withInt b: Int) {}
	@objc func f2(_ y: Int, withOtherInt b: Int) {}
	}

	// Names need to match up for an Objective-C protocol as well.
	class X5d : P5 {
	@objc(f2WithY:withInt:) func f2(_ y: Int, withInt a: Int) {} // expected-error {{Objective-C method 'f2WithY:withInt:' provided by method 'f2(_:withInt:)' does not match the requirement's selector ('f2:withInt:')}}
	@objc(f2WithY:withOtherValue:) func f2(_ y: Int, withOtherInt a: Int) {} // expected-error{{Objective-C method 'f2WithY:withOtherValue:' provided by method 'f2(_:withOtherInt:)' does not match the requirement's selector ('f2:withOtherInt:')}}
	}

	// Distinguish names within tuple arguments.
	typealias T0 = (x: Int, y: String)
	typealias T1 = (xx: Int, y: String)

	func f(_ args: T0) {
	}

	func f(_ args: T1) {
	}

	f(T0(1, "Hi"))

	infix operator ~>> : MaxPrecedence
	precedencegroup MaxPrecedence { higherThan: BitwiseShiftPrecedence }

	func ~>> (x: Int, args: T0) {}
	func ~>> (x: Int, args: T1) {}

	3~>>T0(1, "Hi")
	3~>>T1(2, "Hi")

	protocol Crankable {
	static func ~>> (x: Self, args: T0)
	static func ~>> (x: Self, args: T1)
	}

	extension Int : Crankable {}

	// Invalid witnesses.
	protocol P6 {
	func foo(_ x: Int)
	func bar(x: Int) // expected-note{{protocol requires function 'bar(x:)' with type '(Int) -> ()'}}
	}
	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() { }
	}

	protocol P6Ownership {
	func thunk__shared(_ x: __shared Int)
	func mismatch__shared(_ x: Int)
	func mismatch__owned(x: Int)
	func thunk__owned__owned(x: __owned Int)

	__consuming func inherits__consuming(x: Int)
	func mismatch__consuming(x: Int)
	__consuming func mismatch__consuming_mutating(x: Int) // expected-note {{protocol requires function 'mismatch__consuming_mutating(x:)' with type '(Int) -> ()'}}
	mutating func mismatch__mutating_consuming(x: Int)
	}
	struct X6Ownership : P6Ownership { // expected-error{{type 'X6Ownership' does not conform to protocol 'P6Ownership'}}
	func thunk__shared(_ x: Int) { } // OK
	func mismatch__shared(_ x: __shared Int) { } // OK
	func mismatch__owned(x: __owned Int) { } // OK
	func thunk__owned__owned(x: Int) { } // OK

	func inherits__consuming(x: Int) { } // OK
	__consuming func mismatch__consuming(x: Int) { } // OK
	mutating func mismatch__consuming_mutating(x: Int) { } // expected-note {{candidate is marked 'mutating' but protocol does not allow it}}
	__consuming func mismatch__mutating_consuming(x: Int) { } // OK - '__consuming' acts as a counterpart to 'nonmutating'
	}

	protocol P7 {
	func foo(_ x: Blarg) // expected-error{{use of undeclared type 'Blarg'}}
	}

	struct X7 : P7 { }

	// Selecting the most specialized witness.
	prefix operator %%%

	protocol P8 {
	func foo()
	}

	prefix func %%% <T : P8>(x: T) -> T { }

	protocol P9 : P8 {
	static prefix func %%% (x: Self) -> Self
	}

	struct X9 : P9 {
	func foo() {}
	}

	prefix func %%%(x: X9) -> X9 { }

	protocol P10 {
	associatedtype Assoc
	func bar(_ x: Assoc)
	}

	struct X10 : P10 {
	typealias Assoc = Int
	func bar(_ x: Int) { }
	func bar<T>(_ x: T) { }
	}

	protocol P11 {
	static func ==(x: Self, y: Self) -> Bool
	}

	protocol P12 {
	associatedtype Index : P1 // expected-note{{unable to infer associated type 'Index' for protocol 'P12'}}
	func getIndex() -> Index
	}

	struct XIndexType : P11 { }

	struct X12 : P12 { // expected-error{{type 'X12' does not conform to protocol 'P12'}}
	func getIndex() -> XIndexType { return XIndexType() } // expected-note{{candidate would match and infer 'Index' = 'XIndexType' if 'XIndexType' conformed to 'P1'}}
	}

	func ==(x: X12.Index, y: X12.Index) -> Bool { return true }

	protocol P13 {}
	protocol P14 {
	static prefix func %%%(_: Self.Type)
	}
	prefix func %%%<P: P13>(_: P.Type) { }
	struct X13: P14, P13 { }