use arrow2::bitmap::utils::fmt;

struct A<'a>(&'a [u8], usize, usize);

impl<'a> std::fmt::Debug for A<'a> {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        fmt(self.0, self.1, self.2, f)
    }
}

#[test]
fn test_debug() -> std::fmt::Result {
    assert_eq!(format!("{:?}", A(&[1], 0, 0)), "[]");
    assert_eq!(format!("{:?}", A(&[0b11000001], 0, 8)), "[0b11000001]");
    assert_eq!(
        format!("{:?}", A(&[0b11000001, 1], 0, 9)),
        "[0b11000001, 0b_______1]"
    );
    assert_eq!(format!("{:?}", A(&[1], 0, 2)), "[0b______01]");
    assert_eq!(format!("{:?}", A(&[1], 1, 2)), "[0b_____00_]");
    assert_eq!(format!("{:?}", A(&[1], 2, 2)), "[0b____00__]");
    assert_eq!(format!("{:?}", A(&[1], 3, 2)), "[0b___00___]");
    assert_eq!(format!("{:?}", A(&[1], 4, 2)), "[0b__00____]");
    assert_eq!(format!("{:?}", A(&[1], 5, 2)), "[0b_00_____]");
    assert_eq!(format!("{:?}", A(&[1], 6, 2)), "[0b00______]");
    assert_eq!(
        format!("{:?}", A(&[0b11000001, 1], 1, 9)),
        "[0b1100000_, 0b______01]"
    );
    // extra bytes are ignored
    assert_eq!(
        format!("{:?}", A(&[0b11000001, 1, 1, 1], 1, 9)),
        "[0b1100000_, 0b______01]"
    );
    assert_eq!(
        format!("{:?}", A(&[0b11000001, 1, 1], 2, 16)),
        "[0b110000__, 0b00000001, 0b______01]"
    );
    Ok(())
}