rust/tests/ui/traits/objects-owned-object-borrowed-method-headerless.rs

// run-pass
// Test invoked `&self` methods on owned objects where the values
// closed over do not contain managed values, and thus the boxes do
// not have headers.

trait FooTrait {
    fn foo(&self) -> usize;
}

struct BarStruct {
    x: usize
}

impl FooTrait for BarStruct {
    fn foo(&self) -> usize {
        self.x
    }
}

pub fn main() {
    let foos: Vec<Box<dyn FooTrait>> = vec![
        Box::new(BarStruct{ x: 0 }) as Box<dyn FooTrait>,
        Box::new(BarStruct{ x: 1 }) as Box<dyn FooTrait>,
        Box::new(BarStruct{ x: 2 }) as Box<dyn FooTrait>,
    ];

    for i in 0..foos.len() {
        assert_eq!(i, foos[i].foo());
    }
}