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// RUN: %target-typecheck-verify-swift -swift-version 5
// Intentionally has lower precedence than assignments and ?:
infix operator %%%% : LowPrecedence
precedencegroup LowPrecedence {
associativity: none
lowerThan: AssignmentPrecedence
}
func %%%%<T, U>(x: T, y: U) -> Int { return 0 }
// Intentionally has lower precedence between assignments and ?:
infix operator %%% : MiddlingPrecedence
precedencegroup MiddlingPrecedence {
associativity: none
higherThan: AssignmentPrecedence
lowerThan: TernaryPrecedence
}
func %%%<T, U>(x: T, y: U) -> Int { return 1 }
func foo() throws -> Int { return 0 }
func bar() throws -> Int { return 0 }
var x = try foo() + bar()
x = try foo() + bar()
x += try foo() + bar()
x += try foo() %%%% bar() // expected-error {{'try' following assignment operator does not cover everything to its right}} // expected-error {{call can throw but is not marked with 'try'}} // expected-warning {{result of operator '%%%%' is unused}}
// expected-note@-1 {{did you mean to use 'try'?}} {{21-21=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{21-21=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{21-21=try! }}
x += try foo() %%% bar()
x = foo() + try bar() // expected-error {{'try' cannot appear to the right of a non-assignment operator}} // expected-error {{call can throw but is not marked with 'try'}}
// expected-note@-1 {{did you mean to use 'try'?}} {{5-5=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{5-5=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{5-5=try! }}
var y = true ? try foo() : try bar() + 0
var z = true ? try foo() : try bar() %%% 0 // expected-error {{'try' following conditional operator does not cover everything to its right}}
var a = try! foo() + bar()
a = try! foo() + bar()
a += try! foo() + bar()
a += try! foo() %%%% bar() // expected-error {{'try!' following assignment operator does not cover everything to its right}} // expected-error {{call can throw but is not marked with 'try'}} // expected-warning {{result of operator '%%%%' is unused}}
// expected-note@-1 {{did you mean to use 'try'?}} {{22-22=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{22-22=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{22-22=try! }}
a += try! foo() %%% bar()
a = foo() + try! bar() // expected-error {{'try!' cannot appear to the right of a non-assignment operator}} // expected-error {{call can throw but is not marked with 'try'}}
// expected-note@-1 {{did you mean to use 'try'?}} {{5-5=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{5-5=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{5-5=try! }}
var b = true ? try! foo() : try! bar() + 0
var c = true ? try! foo() : try! bar() %%% 0 // expected-error {{'try!' following conditional operator does not cover everything to its right}}
infix operator ?+= : AssignmentPrecedence
func ?+=(lhs: inout Int?, rhs: Int?) {
lhs = lhs! + rhs!
}
var i = try? foo() + bar()
let _: Double = i // expected-error {{cannot convert value of type 'Int?' to specified type 'Double'}}
i = try? foo() + bar()
i ?+= try? foo() + bar()
i ?+= try? foo() %%%% bar() // expected-error {{'try?' following assignment operator does not cover everything to its right}} // expected-error {{call can throw but is not marked with 'try'}} // expected-warning {{result of operator '%%%%' is unused}}
// expected-note@-1 {{did you mean to use 'try'?}} {{23-23=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{23-23=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{23-23=try! }}
i ?+= try? foo() %%% bar()
_ = foo() == try? bar() // expected-error {{'try?' cannot appear to the right of a non-assignment operator}} // expected-error {{call can throw but is not marked with 'try'}}
// expected-note@-1 {{did you mean to use 'try'?}} {{5-5=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{5-5=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{5-5=try! }}
_ = (try? foo()) == bar() // expected-error {{call can throw but is not marked with 'try'}}
// expected-note@-1 {{did you mean to use 'try'?}} {{21-21=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{21-21=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{21-21=try! }}
_ = foo() == (try? bar()) // expected-error {{call can throw but is not marked with 'try'}}
// expected-note@-1 {{did you mean to use 'try'?}} {{5-5=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{5-5=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{5-5=try! }}
_ = (try? foo()) == (try? bar())
let j = true ? try? foo() : try? bar() + 0
let k = true ? try? foo() : try? bar() %%% 0 // expected-error {{'try?' following conditional operator does not cover everything to its right}}
try let singleLet = foo() // expected-error {{'try' must be placed on the initial value expression}} {{1-5=}} {{21-21=try }}
try var singleVar = foo() // expected-error {{'try' must be placed on the initial value expression}} {{1-5=}} {{21-21=try }}
try let uninit: Int // expected-error {{'try' must be placed on the initial value expression}}
try let (destructure1, destructure2) = (foo(), bar()) // expected-error {{'try' must be placed on the initial value expression}} {{1-5=}} {{40-40=try }}
try let multi1 = foo(), multi2 = bar() // expected-error {{'try' must be placed on the initial value expression}} expected-error 2 {{call can throw but is not marked with 'try'}}
// expected-note@-1 {{did you mean to use 'try'?}} {{18-18=try }} expected-note@-1 {{did you mean to use 'try'?}} {{34-34=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{18-18=try? }} expected-note@-2 {{did you mean to handle error as optional value?}} {{34-34=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{18-18=try! }} expected-note@-3 {{did you mean to disable error propagation?}} {{34-34=try! }}
class TryDecl { // expected-note {{in declaration of 'TryDecl'}}
try let singleLet = foo() // expected-error {{'try' must be placed on the initial value expression}} {{3-7=}} {{23-23=try }}
// expected-error @-1 {{call can throw, but errors cannot be thrown out of a property initializer}}
try var singleVar = foo() // expected-error {{'try' must be placed on the initial value expression}} {{3-7=}} {{23-23=try }}
// expected-error @-1 {{call can throw, but errors cannot be thrown out of a property initializer}}
try // expected-error {{expected declaration}}
func method() {}
}
func test() throws -> Int {
try while true { // expected-error {{'try' cannot be used with 'while'}}
try break // expected-error {{'try' cannot be used with 'break'}}
}
try throw // expected-error {{'try' must be placed on the thrown expression}} {{+1:3-3=try }} {{3-7=}} expected-error {{expected expression in 'throw' statement}}
; // Reset parser.
try return // expected-error {{'try' cannot be used with 'return'}} expected-error {{non-void function should return a value}}
; // Reset parser.
try throw foo() // expected-error {{'try' must be placed on the thrown expression}} {{3-7=}} {{13-13=try }}
// expected-error@-1 {{thrown expression type 'Int' does not conform to 'Error'}}
try return foo() // expected-error {{'try' must be placed on the returned expression}} {{3-7=}} {{14-14=try }}
}
// Test operators.
func *(a : String, b : String) throws -> Int { return 42 }
let _ = "foo"
* // expected-error {{operator can throw but expression is not marked with 'try'}}
// expected-note@-1 {{did you mean to use 'try'?}} {{9-9=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{9-9=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{9-9=try! }}
"bar"
let _ = try! "foo"*"bar"
let _ = try? "foo"*"bar"
let _ = (try? "foo"*"bar") ?? 0
// <rdar://problem/21414023> Assertion failure when compiling function that takes throwing functions and rethrows
func rethrowsDispatchError(handleError: ((Error) throws -> ()), body: () throws -> ()) rethrows {
do {
body() // expected-error {{call can throw but is not marked with 'try'}}
// expected-note@-1 {{did you mean to use 'try'?}} {{5-5=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{5-5=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{5-5=try! }}
} catch {
}
}
// <rdar://problem/21432429> Calling rethrows from rethrows crashes Swift compiler
struct r21432429 {
func x(_ f: () throws -> ()) rethrows {}
func y(_ f: () throws -> ()) rethrows {
x(f) // expected-error {{call can throw but is not marked with 'try'}} expected-note {{call is to 'rethrows' function, but argument function can throw}}
}
}
// <rdar://problem/21427855> Swift 2: Omitting try from call to throwing closure in rethrowing function crashes compiler
func callThrowingClosureWithoutTry(closure: (Int) throws -> Int) rethrows {
closure(0) // expected-error {{call can throw but is not marked with 'try'}} expected-warning {{result of call to function returning 'Int' is unused}}
// expected-note@-1 {{did you mean to use 'try'?}} {{3-3=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{3-3=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{3-3=try! }}
}
func producesOptional() throws -> Int? { return nil }
let singleOptional = try? producesOptional()
let _: String = singleOptional // expected-error {{cannot convert value of type 'Int?' to specified type 'String'}}
let _ = (try? foo())!! // expected-error {{cannot force unwrap value of non-optional type 'Int'}}
func producesDoubleOptional() throws -> Int?? { return 3 }
let _: String = try? producesDoubleOptional() // expected-error {{cannot convert value of type 'Int??' to specified type 'String'}}
func maybeThrow() throws {}
try maybeThrow() // okay
try! maybeThrow() // okay
try? maybeThrow() // okay since return type of maybeThrow is Void
_ = try? maybeThrow() // okay
let _: () -> Void = { try! maybeThrow() } // okay
let _: () -> Void = { try? maybeThrow() } // okay since return type of maybeThrow is Void
if try? maybeThrow() { // expected-error {{cannot be used as a boolean}} {{4-4=((}} {{21-21=) != nil)}}
}
let _: Int = try? foo() // expected-error {{value of optional type 'Int?' not unwrapped; did you mean to use 'try!' or chain with '?'?}} {{14-18=try!}}
class X {}
func test(_: X) {}
func producesObject() throws -> AnyObject { return X() }
test(try producesObject()) // expected-error {{'AnyObject' is not convertible to 'X'}}
// expected-note@-1{{did you mean to use 'as!' to force downcast?}} {{26-26= as! X}}
_ = "a\(try maybeThrow())b"
_ = try "a\(maybeThrow())b"
_ = "a\(maybeThrow())" // expected-error {{call can throw but is not marked with 'try'}}
// expected-note@-1 {{did you mean to use 'try'?}} {{9-9=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{9-9=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{9-9=try! }}
extension DefaultStringInterpolation {
mutating func appendInterpolation() throws {}
}
_ = try "a\()b"
_ = "a\()b" // expected-error {{interpolation can throw but is not marked with 'try'}}
// expected-note@-1 {{did you mean to use 'try'?}} {{5-5=try }}
// expected-note@-2 {{did you mean to handle error as optional value?}} {{5-5=try? }}
// expected-note@-3 {{did you mean to disable error propagation?}} {{5-5=try! }}
_ = try "\() \(1)"
func testGenericOptionalTry<T>(_ call: () throws -> T ) {
let _: String = try? call() // expected-error {{cannot convert value of type 'T?' to specified type 'String'}}
}
func genericOptionalTry<T>(_ call: () throws -> T ) -> T? {
let x = try? call() // no error expected
return x
}
// Test with a non-optional type
let _: String = genericOptionalTry({ () throws -> Int in return 3 }) // expected-error {{cannot convert value of type 'Int?' to specified type 'String'}}
// Test with an optional type
let _: String = genericOptionalTry({ () throws -> Int? in return nil }) // expected-error {{cannot convert value of type 'Int??' to specified type 'String'}}
func produceAny() throws -> Any {
return 3
}
let _: Int? = try? produceAny() as? Int // good
let _: Int? = (try? produceAny()) as? Int // good
let _: String = try? produceAny() as? Int // expected-error {{cannot convert value of type 'Int?' to specified type 'String'}}
let _: String = (try? produceAny()) as? Int // expected-error {{cannot convert value of type 'Int?' to specified type 'String'}}
struct ThingProducer {
func produceInt() throws -> Int { return 3 }
func produceIntNoThrowing() -> Int { return 3 }
func produceAny() throws -> Any { return 3 }
func produceOptionalAny() throws -> Any? { return 3 }
func produceDoubleOptionalInt() throws -> Int?? { return 3 }
}
let optProducer: ThingProducer? = ThingProducer()
let _: Int? = try? optProducer?.produceInt()
let _: Int = try? optProducer?.produceInt() // expected-error {{cannot convert value of type 'Int?' to specified type 'Int'}}
let _: String = try? optProducer?.produceInt() // expected-error {{cannot convert value of type 'Int?' to specified type 'String'}}
let _: Int?? = try? optProducer?.produceInt() // This was the expected type before Swift 5, but this still works; just adds more optional-ness
let _: Int? = try? optProducer?.produceIntNoThrowing() // expected-warning {{no calls to throwing functions occur within 'try' expression}}
let _: Int? = (try? optProducer?.produceAny()) as? Int // good
let _: Int? = try? optProducer?.produceAny() as? Int // good
let _: Int?? = try? optProducer?.produceAny() as? Int // good
let _: String = try? optProducer?.produceAny() as? Int // expected-error {{cannot convert value of type 'Int?' to specified type 'String'}}
let _: String = try? optProducer?.produceDoubleOptionalInt() // expected-error {{cannot convert value of type 'Int??' to specified type 'String'}}
let producer = ThingProducer()
let _: Int = try? producer.produceDoubleOptionalInt() // expected-error {{cannot convert value of type 'Int??' to specified type 'Int'}}
// We don't offer 'try!' here because it would not change the type of the expression in Swift 5+
let _: Int? = try? producer.produceDoubleOptionalInt() // expected-error {{cannot convert value of type 'Int??' to specified type 'Int?'}}
let _: Int?? = try? producer.produceDoubleOptionalInt() // good
let _: Int??? = try? producer.produceDoubleOptionalInt() // good
let _: String = try? producer.produceDoubleOptionalInt() // expected-error {{cannot convert value of type 'Int??' to specified type 'String'}}
// rdar://problem/46742002
protocol Dummy : AnyObject {}
class F<T> {
func wait() throws -> T { fatalError() }
}
func bar(_ a: F<Dummy>, _ b: F<Dummy>) {
_ = (try? a.wait()) === (try? b.wait())
}
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