rust/tests/ui/impl-trait/dyn-trait-return-should-be-impl-trait.rs
2023-01-11 09:32:08 +00:00

75 lines
1.4 KiB
Rust

#![allow(bare_trait_objects)]
struct Struct;
trait Trait {}
impl Trait for Struct {}
impl Trait for u32 {}
fn fuz() -> (usize, Trait) { (42, Struct) }
//~^ ERROR E0277
//~| ERROR E0308
fn bar() -> (usize, dyn Trait) { (42, Struct) }
//~^ ERROR E0277
//~| ERROR E0308
fn bap() -> Trait { Struct }
//~^ ERROR E0746
fn ban() -> dyn Trait { Struct }
//~^ ERROR E0746
fn bak() -> dyn Trait { unimplemented!() } //~ ERROR E0746
// Suggest using `Box<dyn Trait>`
fn bal() -> dyn Trait { //~ ERROR E0746
if true {
return Struct;
}
42
}
fn bax() -> dyn Trait { //~ ERROR E0746
if true {
Struct
} else {
42 //~ ERROR `if` and `else` have incompatible types
}
}
fn bam() -> Box<dyn Trait> {
if true {
return Struct; //~ ERROR mismatched types
}
42 //~ ERROR mismatched types
}
fn baq() -> Box<dyn Trait> {
if true {
return 0; //~ ERROR mismatched types
}
42 //~ ERROR mismatched types
}
fn baz() -> Box<dyn Trait> {
if true {
Struct //~ ERROR mismatched types
} else {
42 //~ ERROR mismatched types
}
}
fn baw() -> Box<dyn Trait> {
if true {
0 //~ ERROR mismatched types
} else {
42 //~ ERROR mismatched types
}
}
// Suggest using `impl Trait`
fn bat() -> dyn Trait { //~ ERROR E0746
if true {
return 0;
}
42
}
fn bay() -> dyn Trait { //~ ERROR E0746
if true {
0
} else {
42
}
}
fn main() {}