// RUN: %target-typecheck-verify-swift -swift-version 4

// rdar://problem/31969605

class Base {}
class Derived : Base {}

protocol Refined {}
protocol Proto : Refined {}
extension Base : Refined {}

func baseFn(_: Base) {}

func superclassConversion(fn: @escaping (Base) -> ()) {
  let _: (Derived) -> () = fn
}

func existentialConversion(fn: @escaping (Refined) -> ()) {
  let _: (Proto) -> () = fn
  let _: (Base) -> () = fn
  let _: (Derived) -> () = fn
}

// rdar://problem/31725325

func a<b>(_: [(String, (b) -> () -> Void)]) {}
func a<b>(_: [(String, (b) -> () throws -> Void)]) {}

class c {
  func e() {}
  static var d = [("", e)]
}
a(c.d)

func b<T>(_: (T) -> () -> ()) {}

b(c.e)

func bar(_: () -> ()) {}
func bar(_: () throws -> ()) {}
func bar_empty() {}

bar(bar_empty)

func consumeNoEscape(_ f: (Int) -> Int) {}
func consumeEscaping(_ f: @escaping (Int) -> Int) {}
func takesAny(_ f: Any)  {}

func twoFns(_ f: (Int) -> Int, _ g: @escaping (Int) -> Int) {
  // expected-note@-1 {{parameter 'f' is implicitly non-escaping}}
  takesAny(f) // expected-error {{converting non-escaping value to 'Any' may allow it to escape}}
  takesAny(g)
  var h = g
  h = f // expected-error {{assigning non-escaping parameter 'f' to an @escaping closure}}
}

takesAny(consumeNoEscape)
takesAny(consumeEscaping)

var noEscapeParam: ((Int) -> Int) -> () = consumeNoEscape // expected-note {{add explicit @escaping to function parameter}}{{21-21=@escaping }}
var escapingParam: (@escaping (Int) -> Int) -> () = consumeEscaping
noEscapeParam = escapingParam // expected-error {{cannot assign value of type '(@escaping (Int) -> Int) -> ()' to type '((Int) -> Int) -> ()'}}
// expected-note@-1{{parameter #0 expects escaping value of type '(Int) -> Int'}}

escapingParam = takesAny
noEscapeParam = takesAny // expected-error {{converting non-escaping value to 'Any' may allow it to escape}}

// rdar://problem/59773317 - Improve type error message when returning (or escaping) a function-typed value as an optional of that type
func rdar_59773317(x: () -> Int) -> (() -> Int)? { // expected-note {{parameter 'x' is implicitly non-escaping}}
  return x // expected-error {{using non-escaping parameter 'x' in a context expecting an @escaping closure}}
}

// rdar://problem/59703585 - Wrong error message when signature of a C function type and Swift implementation mismatch
func rdar_59703585() {
  typealias Fn = @convention(c) (UnsafePointer<Int8>?, UnsafeMutableRawPointer?) -> Void

  func swiftCallback(someString: UnsafePointer<Int8>, someObject: UnsafeMutableRawPointer?) {}

  var cb: Fn? = nil

  cb = swiftCallback
  // expected-error@-1 {{cannot assign value of type '(UnsafePointer<Int8>, UnsafeMutableRawPointer?) -> ()' to type 'Fn' (aka '@convention(c) (Optional<UnsafePointer<Int8>>, Optional<UnsafeMutableRawPointer>) -> ()')}}
}

// https://github.com/apple/swift/issues/57216
do {
  var v1: (inout Float) -> ()
  v1 = { (_: inout Int) in }
  // expected-error@-1{{cannot assign value of type '(inout Int) -> ()' to type '(inout Float) -> ()'}}

  var v2: (Int , inout Float) -> ()
  v2 = { (_: Int, _: inout Int) in }
  // expected-error@-1{{cannot assign value of type '(Int, inout Int) -> ()' to type '(Int, inout Float) -> ()'}}
}