Files
swift-mirror/test/Constraints/valid_pointer_conversions.swift
Pavel Yaskevich 70ac657a46 [CSBindings] Don't delay bindings inferred through inout conversion
Delaying such bindings is too restrictive and leads to subpar selections.

For `$T1` to be array or C-style pointer it would have to be
connected either to a type variable that could be bound to
array/pointer or directly to array/pointer type which would
result in the solver either selecting the other type variable
first (because it appears in adjacent variables of `$T1`) or
provide an additional binding(s) for `$T1` (including literals).

Consider the following constraint system:

```
$T2 arg conv $T1
$T2 conforms ExpressibleByIntegerLiteral

inout $T1 arg conv UnsafeMutablePointer<UInt8>?
```

If `$T1` and `$T2` are the only viable type variables delaying
`$T1` would mean that `$T2` is picked to attempt its default
type `Int` which is incorrect (it doesn't get `UInt8` because
there is no transitive inference through conversions).
2024-10-31 11:58:55 -07:00

91 lines
3.3 KiB
Swift

// RUN: %target-typecheck-verify-swift
func foo(_ a: [[UInt8]], _ p: [UnsafeRawPointer]) {
foo(a, a) // expect-warning {{all paths through this function will call itself}}
}
// rdar://problem/44658089
func takesPtr(_: UnsafePointer<UInt8>) {}
func takesDoubleOptionalPtr(_ x: UnsafeRawPointer??) {}
func takesMutableDoubleOptionalPtr(_ x: UnsafeMutableRawPointer??) {}
func takesMutableDoubleOptionalTypedPtr(_ x: UnsafeMutablePointer<Double>??) {}
func givesPtr(_ str: String) {
takesPtr(UnsafePointer(str)) // expected-warning {{initialization of 'UnsafePointer<UInt8>' results in a dangling pointer}}
// expected-note @-1 {{implicit argument conversion from 'String' to 'UnsafePointer<UInt8>' produces a pointer valid only for the duration of the call to 'init(_:)'}}
// expected-note@-2 {{use the 'withCString' method on String in order to explicitly convert argument to pointer valid for a defined scope}}
var i = 0
var d = 0.0
var arr = [1, 2, 3]
// https://github.com/apple/swift/issues/51587
// Allow double optional promotion for pointer conversions.
takesDoubleOptionalPtr(&arr)
takesDoubleOptionalPtr(arr)
takesDoubleOptionalPtr(str)
takesMutableDoubleOptionalPtr(&i)
takesMutableDoubleOptionalPtr(&arr)
takesMutableDoubleOptionalTypedPtr(&d)
takesDoubleOptionalPtr(i) // expected-error {{cannot convert value of type 'Int' to expected argument type 'UnsafeRawPointer?'}}
takesMutableDoubleOptionalPtr(arr) // expected-error {{cannot convert value of type '[Int]' to expected argument type 'UnsafeMutableRawPointer?'}}
takesMutableDoubleOptionalTypedPtr(&i) // expected-error {{cannot convert value of type 'UnsafeMutablePointer<Int>' to expected argument type 'UnsafeMutablePointer<Double>'}}
// expected-note@-1 {{arguments to generic parameter 'Pointee' ('Int' and 'Double') are expected to be equal}}
}
// https://github.com/apple/swift/issues/54818
do {
func f(_ x: UnsafeMutablePointer<Double>??) {}
var i = 0
f(&i)
// expected-error@-1 {{cannot convert value of type 'UnsafeMutablePointer<Int>' to expected argument type 'UnsafeMutablePointer<Double>'}}
// expected-note@-2 {{arguments to generic parameter 'Pointee' ('Int' and 'Double') are expected to be equal}}
}
//problem/68254165 - Bad diagnostic when using String init(decodingCString:) with an incorrect pointer type
func rdar68254165(ptr: UnsafeMutablePointer<Int8>) {
_ = String(decodingCString: ptr, as: .utf8) // expected-error {{generic parameter 'Encoding' could not be inferred}}
}
// The base of leading-dot syntax could be inferred through an implicit pointer conversion.
do {
struct S {
static var prop = S()
}
func inference_through_optional(_ ptr: UnsafePointer<S>?) {}
inference_through_optional(&.prop) // Ok
func inference_through_force_unwrap(name: String) {
func test(_: UnsafeMutablePointer<Float>!) {}
var outputs = [String: [Float]]()
test(&outputs[name]!) // Ok
}
}
do {
func test<O>(_ initialValue: O, _ action: (inout O) -> Void) -> O {
}
func compute(_: UnsafeMutablePointer<UInt8>!) {
}
let result1 = test(0) { // `0` should be inferred as `UInt8`
compute(&$0)
}
let result2 = test([0]) { // `0` should be inferred as `UInt8`
compute(&$0)
}
let _: UInt8 = result1 // Ok
let _: [UInt8] = result2 // Ok
}