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// RUN: %target-swift-frontend -strict-concurrency=complete -emit-sil -o /dev/null %s -verify -disable-availability-checking
// REQUIRES: concurrency
@available(SwiftStdlib 5.1, *)
struct S: AsyncSequence {
typealias Element = Int
struct AsyncIterator: AsyncIteratorProtocol {
mutating func next() async -> Int? { nil }
}
func makeAsyncIterator() -> AsyncIterator { AsyncIterator() }
}
@available(SwiftStdlib 5.1, *)
struct TS: AsyncSequence {
typealias Element = Int
struct AsyncIterator: AsyncIteratorProtocol {
mutating func next() async throws -> Int? { nil }
}
func makeAsyncIterator() -> AsyncIterator { AsyncIterator() }
}
@available(SwiftStdlib 5.1, *)
struct SpecificTS<F: Error>: AsyncSequence {
typealias Element = Int
typealias Failure = F
struct AsyncIterator: AsyncIteratorProtocol {
typealias Failure = F
mutating func next() async throws -> Int? { nil }
}
func makeAsyncIterator() -> AsyncIterator { AsyncIterator() }
}
@available(SwiftStdlib 5.1, *)
struct GenericTS<Failure: Error>: AsyncSequence {
typealias Element = Int
struct AsyncIterator: AsyncIteratorProtocol {
mutating func next() async throws -> Int? { nil }
}
func makeAsyncIterator() -> AsyncIterator { AsyncIterator() }
}
@available(SwiftStdlib 5.1, *)
struct SequenceAdapter<Base: AsyncSequence>: AsyncSequence {
typealias Element = Base.Element
struct AsyncIterator: AsyncIteratorProtocol {
mutating func next() async rethrows -> Base.Element? { nil }
}
func makeAsyncIterator() -> AsyncIterator { AsyncIterator() }
}
public struct NormalThrowingAsyncSequence<Element, Failure>: AsyncSequence {
private let iteratorMaker: () -> AsyncIterator
public struct AsyncIterator: AsyncIteratorProtocol {
let nextMaker: () async throws -> Element?
public mutating func next() async throws -> Element? {
try await nextMaker()
}
}
public func makeAsyncIterator() -> AsyncIterator {
iteratorMaker()
}
}
enum MyError: Error {
case fail
}
@available(SwiftStdlib 5.1, *)
func testAssocTypeInference(sf: S.Failure, tsf: TS.Failure, gtsf1: GenericTS<MyError>.Failure, adapter: SequenceAdapter<SpecificTS<MyError>>.Failure, ntas: NormalThrowingAsyncSequence<String, MyError>.Failure) {
let _: Int = sf // expected-error{{cannot convert value of type 'S.__AsyncSequence_Failure' (aka 'Never') to specified type 'Int'}}
let _: Int = tsf // expected-error{{cannot convert value of type 'TS.__AsyncSequence_Failure' (aka 'any Error') to specified type 'Int'}}
let _: Int = gtsf1 // expected-error{{cannot convert value of type 'GenericTS<MyError>.__AsyncSequence_Failure' (aka 'any Error') to specified type 'Int'}}
let _: Int = adapter // expected-error{{cannot convert value of type 'SequenceAdapter<SpecificTS<MyError>>.__AsyncSequence_Failure' (aka 'MyError') to specified type 'Int'}}
let _: Int = ntas // expected-error{{cannot convert value of type 'NormalThrowingAsyncSequence<String, MyError>.__AsyncSequence_Failure' (aka 'any Error') to specified type 'Int'}}
}
@available(SwiftStdlib 5.1, *)
func test(s: S) async {
for await x in s { _ = x }
}
enum OtherError: Error {
case boom
}
@available(SwiftStdlib 5.1, *)
func testMyError(s: SpecificTS<MyError>, so: SpecificTS<OtherError>) async throws(MyError) {
for try await x in s { _ = x }
for try await x in so { _ = x }
// expected-error@-1{{thrown expression type 'SpecificTS<OtherError>.AsyncIterator.Failure' (aka 'OtherError') cannot be converted to error type 'MyError'}}
}
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