rust/tests/ui/suggestions/issue-86100-tuple-paren-comma.rs
2023-01-11 09:32:08 +00:00

26 lines
812 B
Rust

// Tests that a suggestion is issued for type mismatch errors when a
// 1-tuple is expected and a parenthesized expression of non-tuple
// type is supplied.
fn foo<T>(_t: (T,)) {}
struct S { _s: (String,) }
fn main() {
let _x: (i32,) = (5);
//~^ ERROR: mismatched types [E0308]
//~| HELP: use a trailing comma to create a tuple with one element
foo((Some(3)));
//~^ ERROR: mismatched types [E0308]
//~| HELP: use a trailing comma to create a tuple with one element
let _s = S { _s: ("abc".to_string()) };
//~^ ERROR: mismatched types [E0308]
//~| HELP: use a trailing comma to create a tuple with one element
// Do not issue the suggestion if the found type is already a tuple.
let t = (1, 2);
let _x: (i32,) = (t);
//~^ ERROR: mismatched types [E0308]
}