src/test/ui/feature-gates/feature-gate-const_in_array_repeat_expressions.rs

#![allow(warnings)]

struct Bar;

// This function would compile with the feature gate, and tests that it is suggested.
fn foo() {
    let arr: [Option<String>; 2] = [None::<String>; 2];
    //~^ ERROR the trait bound `Option<String>: Copy` is not satisfied [E0277]
}

// This function would not compile with the feature gate, and tests that it is not suggested.
fn bar() {
    let arr: [Option<String>; 2] = [Some("foo".to_string()); 2];
    //~^ ERROR the trait bound `Option<String>: Copy` is not satisfied [E0277]
}

fn main() {}