#![feature(plugin)]
#![plugin(clippy)]

struct One;

#[deny(len_without_is_empty)]
impl One {
	fn len(self: &Self) -> isize { //~ERROR
		1
	}
}

#[deny(len_without_is_empty)]
trait TraitsToo {
	fn len(self: &Self) -> isize; //~ERROR
}

impl TraitsToo for One {
	fn len(self: &Self) -> isize {
		0
	}
}

#[allow(dead_code)]
struct HasIsEmpty;

#[deny(len_without_is_empty)]
#[allow(dead_code)]
impl HasIsEmpty {
	fn len(self: &Self) -> isize {
		1
	}
	
	fn is_empty() -> bool {
		false
	}
}

#[deny(len_zero)]
fn main() {
	let x = [1, 2];
	if x.len() == 0 { //~ERROR
		println!("This should not happen!");
	}
	
	let y = One;
	// false positives here
	if y.len()  == 0 { //~ERROR
		println!("This should not happen either!");
	}
	
	let z : &TraitsToo = &y;
	if z.len() > 0 { //~ERROR
		println!("Nor should this!");
	}
}