Files
swift-mirror/test/Constraints/variadic_generic_constraints.swift
Pavel Yaskevich 4804f2131b [CSSimplify] Narrow down tuple wrapping for pack expansion matching
Follow-up for https://github.com/swiftlang/swift/pull/82326.

The optional injection is only viable is the wrapped type is
not yet resolved, otherwise it's safe to wrap the optional.
2025-06-24 15:30:25 -07:00

105 lines
3.6 KiB
Swift

// RUN: %target-typecheck-verify-swift
// Test instantiation of constraint solver constraints from generic requirements
// involving type pack parameters
// Conformance requirements
protocol P {}
func takesP<each T: P>(_: repeat each T) {} // expected-note {{where 'each T' = 'DoesNotConformToP'}}
struct ConformsToP: P {}
struct DoesNotConformToP {}
takesP() // ok
takesP(ConformsToP(), ConformsToP(), ConformsToP()) // ok
takesP(ConformsToP(), DoesNotConformToP(), ConformsToP()) // expected-error {{global function 'takesP' requires that 'DoesNotConformToP' conform to 'P'}}
// Superclass requirements
class C {}
class SubclassOfC: C {}
class NotSubclassOfC {}
func takesC<each T: C>(_: repeat each T) {} // expected-note {{where 'each T' = 'NotSubclassOfC'}}
takesC() // ok
takesC(SubclassOfC(), SubclassOfC(), SubclassOfC()) // ok
takesC(SubclassOfC(), NotSubclassOfC(), SubclassOfC()) // expected-error {{global function 'takesC' requires that 'NotSubclassOfC' inherit from 'C'}}
// Layout requirements
struct S {}
func takesAnyObject<each T: AnyObject>(_: repeat each T) {}
takesAnyObject()
takesAnyObject(C(), C(), C())
// FIXME: Bad diagnostic
takesAnyObject(C(), S(), C()) // expected-error {{type of expression is ambiguous without a type annotation}}
// Same-type requirements
// expected-note@+1 {{where '(each T).Element' = 'String', '(each U).Element' = 'Int'}}
func takesParallelSequences<each T, each U>(t: repeat each T, u: repeat each U)
where repeat each T: Sequence,
repeat each U: Sequence,
repeat (each T).Element == (each U).Element {}
takesParallelSequences() // ok
takesParallelSequences(t: Array<Int>(), u: Set<Int>()) // ok
takesParallelSequences(t: Array<String>(), Set<Int>(), u: Set<String>(), Array<Int>()) // ok
takesParallelSequences(t: Array<String>(), Set<Int>(), u: Array<Int>(), Set<String>()) // expected-error {{global function 'takesParallelSequences(t:u:)' requires the types 'String' and 'Int' be equivalent}}
// Same-shape requirements
func zip<each T, each U>(t: repeat each T, u: repeat each U) -> (repeat (each T, each U)) {}
// expected-note@-1 {{'zip(t:u:)' declared here}}
let _ = zip() // ok
let _ = zip(t: 1, u: "hi") // ok
let _ = zip(t: 1, 2, u: "hi", "hello") // ok
let _ = zip(t: 1, 2, 3, u: "hi", "hello", "greetings") // ok
let _ = zip(t: 1, u: "hi", "hello", "greetings") // expected-error {{extra arguments at positions #3, #4 in call}}
// expected-error@-1 {{global function 'zip(t:u:)' requires the type packs 'Int' and 'String, String, String' have the same shape}}
func goodCallToZip<each T, each U>(t: repeat each T, u: repeat each U) where (repeat (each T, each U)): Any {
_ = zip(t: repeat each t, u: repeat each u)
}
func badCallToZip<each T, each U>(t: repeat each T, u: repeat each U) {
_ = zip(t: repeat each t, u: repeat each u)
// expected-error@-1 {{global function 'zip(t:u:)' requires the type packs 'each T' and 'each U' have the same shape}}
// expected-error@-2 {{pack expansion requires that 'each U' and 'each T' have the same shape}}
}
func variadicGenericsInOptionalContext(v: Int?) {
func test1<A, B, each C>(
_: A,
_: B,
_: repeat each C
) throws -> (A, B, repeat each C) {
fatalError()
}
func test2<A, B, each C>(
_: A,
_: B,
_: (repeat each C)
) throws -> (A, B, repeat each C) {
fatalError()
}
func test() {
guard let _ = try? test1(1, 2, 3) else { return } // Ok
guard let _ = try? test1(1, 2, v) else { return } // Ok
guard let _ = try? test2(1, 2, 3) else { return } // Ok
guard let _ = try? test2(1, 2, v) else { return } // Ok
}
}