| // RUN: %target-swift-frontend -typecheck -verify -swift-version 4 %s |
| |
| let s = "Hello" |
| let ss = s[s.startIndex..<s.endIndex] |
| |
| // CTP_Initialization |
| do { |
| let s1: String = { return ss }() // expected-error {{cannot convert value of type 'Substring' to specified type 'String'}} {{20-20=String(}} {{35-35=)}} |
| _ = s1 |
| } |
| |
| // CTP_ReturnStmt |
| do { |
| func returnsAString() -> String { |
| return ss // expected-error {{cannot convert return expression of type 'Substring' to return type 'String'}} {{12-12=String(}} {{14-14=)}} |
| } |
| } |
| |
| // CTP_ThrowStmt |
| // Doesn't really make sense for this fix-it - see case in diagnoseContextualConversionError: |
| // The conversion destination of throw is always ErrorType (at the moment) |
| // if this ever expands, this should be a specific form like () is for |
| // return. |
| |
| // CTP_EnumCaseRawValue |
| // Substrings can't be raw values because they aren't literals. |
| |
| // CTP_DefaultParameter |
| do { |
| func foo(x: String = ss) {} // expected-error {{default argument value of type 'Substring' cannot be converted to type 'String'}} {{24-24=String(}} {{26-26=)}} |
| } |
| |
| // CTP_CalleeResult |
| do { |
| func getSubstring() -> Substring { return ss } |
| let gottenString : String = getSubstring() // expected-error {{cannot convert value of type 'Substring' to specified type 'String'}} {{31-31=String(}} {{45-45=)}} |
| _ = gottenString |
| } |
| |
| // CTP_CallArgument |
| do { |
| func takesAString(_ s: String) {} |
| takesAString(ss) // expected-error {{cannot convert value of type 'Substring' to expected argument type 'String'}} {{16-16=String(}} {{18-18=)}} |
| } |
| |
| // CTP_ClosureResult |
| do { |
| [ss].map { (x: Substring) -> String in x } // expected-error {{cannot convert value of type 'Substring' to closure result type 'String'}} {{42-42=String(}} {{43-43=)}} |
| } |
| |
| // CTP_ArrayElement |
| do { |
| let a: [String] = [ ss ] // expected-error {{cannot convert value of type 'Substring' to expected element type 'String'}} {{23-23=String(}} {{25-25=)}} |
| _ = a |
| } |
| |
| // CTP_DictionaryKey |
| do { |
| let d: [ String : String ] = [ ss : s ] // expected-error {{cannot convert value of type 'Substring' to expected dictionary key type 'String'}} {{34-34=String(}} {{36-36=)}} |
| _ = d |
| } |
| |
| // CTP_DictionaryValue |
| do { |
| let d: [ String : String ] = [ s : ss ] // expected-error {{cannot convert value of type 'Substring' to expected dictionary value type 'String'}} {{38-38=String(}} {{40-40=)}} |
| _ = d |
| } |
| |
| // CTP_CoerceOperand |
| do { |
| let s1: String = ss as String // expected-error {{cannot convert value of type 'Substring' to type 'String' in coercion}} {{20-20=String(}} {{22-22=)}} |
| _ = s1 |
| } |
| |
| // CTP_AssignSource |
| do { |
| let s1: String = ss // expected-error {{cannot convert value of type 'Substring' to specified type 'String'}} {{20-20=String(}} {{22-22=)}} |
| _ = s1 |
| } |
| |
| // Substring-to-String via subscripting in a context expecting String |
| func takesString(_ s: String) {} |
| |
| func apply(_ fn: (String) -> (), _ s: String) { |
| fn(s[s.startIndex..<s.endIndex]) // expected-error{{subscripts returning String were obsoleted in Swift 4; explicitly construct a String from subscripted result}} {{6-6=String(}} {{34-34=)}} |
| let _: String = s[s.startIndex..<s.endIndex] // expected-error{{subscripts returning String were obsoleted in Swift 4; explicitly construct a String from subscripted result}} {{19-19=String(}} {{47-47=)}} |
| _ = s[s.startIndex..<s.endIndex] as String // expected-error{{subscripts returning String were obsoleted in Swift 4; explicitly construct a String from subscripted result}} {{7-7=String(}} {{35-35=)}} |
| } |
| |
| // rdar://33474838 |
| protocol Derivable { |
| func derive() -> Substring |
| } |
| func foo<T: Derivable>(t: T) -> String { |
| return t.derive() // expected-error {{cannot convert return expression of type 'Substring' to return type 'String'}} {{10-10=String(}} {{20-20=)}} |
| } |