rust/tests/ui/coercion/coerce-to-bang.rs
2023-01-11 09:32:08 +00:00

80 lines
1.9 KiB
Rust

#![feature(never_type)]
fn foo(x: usize, y: !, z: usize) { }
fn call_foo_a() {
foo(return, 22, 44);
//~^ ERROR mismatched types
}
fn call_foo_b() {
// Divergence happens in the argument itself, definitely ok.
foo(22, return, 44);
}
fn call_foo_c() {
// This test fails because the divergence happens **after** the
// coercion to `!`:
foo(22, 44, return); //~ ERROR mismatched types
}
fn call_foo_d() {
// This test passes because `a` has type `!`:
let a: ! = return;
let b = 22;
let c = 44;
foo(a, b, c); // ... and hence a reference to `a` is expected to diverge.
//~^ ERROR mismatched types
}
fn call_foo_e() {
// This test probably could pass but we don't *know* that `a`
// has type `!` so we don't let it work.
let a = return;
let b = 22;
let c = 44;
foo(a, b, c); //~ ERROR mismatched types
}
fn call_foo_f() {
// This fn fails because `a` has type `usize`, and hence a
// reference to is it **not** considered to diverge.
let a: usize = return;
let b = 22;
let c = 44;
foo(a, b, c); //~ ERROR mismatched types
}
fn array_a() {
// Return is coerced to `!` just fine, but `22` cannot be.
let x: [!; 2] = [return, 22]; //~ ERROR mismatched types
}
fn array_b() {
// Error: divergence has not yet occurred.
let x: [!; 2] = [22, return]; //~ ERROR mismatched types
}
fn tuple_a() {
// No divergence at all.
let x: (usize, !, usize) = (22, 44, 66); //~ ERROR mismatched types
}
fn tuple_b() {
// Divergence happens before coercion: OK
let x: (usize, !, usize) = (return, 44, 66);
//~^ ERROR mismatched types
}
fn tuple_c() {
// Divergence happens before coercion: OK
let x: (usize, !, usize) = (22, return, 66);
}
fn tuple_d() {
// Error: divergence happens too late
let x: (usize, !, usize) = (22, 44, return); //~ ERROR mismatched types
}
fn main() { }