Function growing

cranelift/entity/src/list.rs:834–868

()

    #[test]
    fn growing() {
        let pool = &mut ListPool::<Inst>::new();
        let mut list = EntityList::<Inst>::default();

        let i1 = Inst::new(1);
        let i2 = Inst::new(2);
        let i3 = Inst::new(3);
        let i4 = Inst::new(4);

        // This is not supposed to change the list.
        list.grow_at(0, 0, pool);
        assert_eq!(list.len(pool), 0);
        assert!(list.is_empty());

        list.grow_at(0, 2, pool);
        assert_eq!(list.len(pool), 2);

        list.as_mut_slice(pool).copy_from_slice(&[i2, i3]);

        list.grow_at(1, 0, pool);
        assert_eq!(list.as_slice(pool), &[i2, i3]);

        list.grow_at(1, 1, pool);
        list.as_mut_slice(pool)[1] = i1;
        assert_eq!(list.as_slice(pool), &[i2, i1, i3]);

        // Append nothing at the end.
        list.grow_at(3, 0, pool);
        assert_eq!(list.as_slice(pool), &[i2, i1, i3]);

        // Append something at the end.
        list.grow_at(3, 1, pool);
        list.as_mut_slice(pool)[3] = i4;
        assert_eq!(list.as_slice(pool), &[i2, i1, i3, i4]);
    }

    #[test]
    fn deep_clone() {