arrayvec/tests/tests.rs

extern crate arrayvec;

use arrayvec::ArrayVec;
use arrayvec::ArrayString;
use std::mem;

use std::collections::HashMap;


#[test]
fn test_simple() {
    use std::ops::Add;

    let mut vec: ArrayVec<[Vec<i32>; 3]> = ArrayVec::new();

    vec.push(vec![1, 2, 3, 4]);
    vec.push(vec![10]);
    vec.push(vec![-1, 13, -2]);

    for elt in &vec {
        assert_eq!(elt.iter().fold(0, Add::add), 10);
    }

    let sum_len = vec.into_iter().map(|x| x.len()).fold(0, Add::add);
    assert_eq!(sum_len, 8);
}

#[test]
fn test_u16_index() {
    const N: usize = 4096;
    let mut vec: ArrayVec<[_; N]> = ArrayVec::new();
    for _ in 0..N {
        assert!(vec.push(1u8).is_none());
    }
    assert!(vec.push(0).is_some());
    assert_eq!(vec.len(), N);
}

#[test]
fn test_iter() {
    let mut iter = ArrayVec::from([1, 2, 3]).into_iter();
    assert_eq!(iter.size_hint(), (3, Some(3)));
    assert_eq!(iter.next_back(), Some(3));
    assert_eq!(iter.next(), Some(1));
    assert_eq!(iter.next_back(), Some(2));
    assert_eq!(iter.size_hint(), (0, Some(0)));
    assert_eq!(iter.next_back(), None);
}

#[test]
fn test_drop() {
    use std::cell::Cell;

    let flag = &Cell::new(0);

    struct Bump<'a>(&'a Cell<i32>);

    impl<'a> Drop for Bump<'a> {
        fn drop(&mut self) {
            let n = self.0.get();
            self.0.set(n + 1);
        }
    }

    {
        let mut array = ArrayVec::<[Bump; 128]>::new();
        array.push(Bump(flag));
        array.push(Bump(flag));
    }
    assert_eq!(flag.get(), 2);

    // test something with the nullable pointer optimization
    flag.set(0);

    {
        let mut array = ArrayVec::<[_; 3]>::new();
        array.push(vec![Bump(flag)]);
        array.push(vec![Bump(flag), Bump(flag)]);
        array.push(vec![]);
        array.push(vec![Bump(flag)]);
        assert_eq!(flag.get(), 1);
        drop(array.pop());
        assert_eq!(flag.get(), 1);
        drop(array.pop());
        assert_eq!(flag.get(), 3);
    }

    assert_eq!(flag.get(), 4);

    // test into_inner
    flag.set(0);
    {
        let mut array = ArrayVec::<[_; 3]>::new();
        array.push(Bump(flag));
        array.push(Bump(flag));
        array.push(Bump(flag));
        let inner = array.into_inner();
        assert!(inner.is_ok());
        assert_eq!(flag.get(), 0);
        drop(inner);
        assert_eq!(flag.get(), 3);
    }

}

#[test]
fn test_extend() {
    let mut range = 0..10;

    let mut array: ArrayVec<[_; 5]> = range.by_ref().collect();
    assert_eq!(&array[..], &[0, 1, 2, 3, 4]);
    assert_eq!(range.next(), Some(5));

    array.extend(range.by_ref());
    assert_eq!(range.next(), Some(6));

    let mut array: ArrayVec<[_; 10]> = (0..3).collect();
    assert_eq!(&array[..], &[0, 1, 2]);
    array.extend(3..5);
    assert_eq!(&array[..], &[0, 1, 2, 3, 4]);
}

#[test]
fn test_is_send_sync() {
    let data = ArrayVec::<[Vec<i32>; 5]>::new();
    &data as &Send;
    &data as &Sync;
}

#[test]
fn test_compact_size() {
    // Future rust will kill these drop flags!
    // 4 elements size + 1 len + 1 enum tag + [1 drop flag]
    type ByteArray = ArrayVec<[u8; 4]>;
    println!("{}", mem::size_of::<ByteArray>());
    assert!(mem::size_of::<ByteArray>() <= 8);

    // 12 element size + 1 enum tag + 3 padding + 1 len + 1 drop flag + 2 padding
    type QuadArray = ArrayVec<[u32; 3]>;
    println!("{}", mem::size_of::<QuadArray>());
    assert!(mem::size_of::<QuadArray>() <= 24);
}

#[test]
fn test_drain() {
    let mut v = ArrayVec::from([0; 8]);
    v.pop();
    v.drain(0..7);
    assert_eq!(&v[..], &[]);

    v.extend(0..);
    v.drain(1..4);
    assert_eq!(&v[..], &[0, 4, 5, 6, 7]);
    let u: ArrayVec<[_; 3]> = v.drain(1..4).rev().collect();
    assert_eq!(&u[..], &[6, 5, 4]);
    assert_eq!(&v[..], &[0, 7]);
    v.drain(..);
    assert_eq!(&v[..], &[]);
}

#[test]
fn test_retain() {
    let mut v = ArrayVec::from([0; 8]);
    for (i, elt) in v.iter_mut().enumerate() {
        *elt = i;
    }
    v.retain(|_| true);
    assert_eq!(&v[..], &[0, 1, 2, 3, 4, 5, 6, 7]);
    v.retain(|elt| {
        *elt /= 2;
        *elt % 2 == 0
    });
    assert_eq!(&v[..], &[0, 0, 2, 2]);
    v.retain(|_| false);
    assert_eq!(&v[..], &[]);
}

#[test]
#[should_panic]
fn test_drain_oob() {
    let mut v = ArrayVec::from([0; 8]);
    v.pop();
    v.drain(0..8);
}

#[test]
#[should_panic]
fn test_drop_panic() {
    struct DropPanic;

    impl Drop for DropPanic {
        fn drop(&mut self) {
            panic!("drop");
        }
    }

    let mut array = ArrayVec::<[DropPanic; 1]>::new();
    array.push(DropPanic);
}

#[test]
#[should_panic]
fn test_drop_panic_into_iter() {
    struct DropPanic;

    impl Drop for DropPanic {
        fn drop(&mut self) {
            panic!("drop");
        }
    }

    let mut array = ArrayVec::<[DropPanic; 1]>::new();
    array.push(DropPanic);
    array.into_iter();
}

#[test]
fn test_insert() {
    let mut v = ArrayVec::from([]);
    assert_eq!(v.push(1), Some(1));
    assert_eq!(v.insert(0, 1), Some(1));

    let mut v = ArrayVec::<[_; 3]>::new();
    v.insert(0, 0);
    v.insert(1, 1);
    v.insert(2, 2);
    v.insert(3, 3);
    assert_eq!(&v[..], &[0, 1, 2]);
    v.insert(1, 9);
    assert_eq!(&v[..], &[0, 9, 1]);

    let mut v = ArrayVec::from([2]);
    assert_eq!(v.insert(1, 1), Some(1));
    assert_eq!(v.insert(2, 1), Some(1));
}

#[test]
fn test_into_inner_1() {
    let mut v = ArrayVec::from([1, 2]);
    v.pop();
    let u = v.clone();
    assert_eq!(v.into_inner(), Err(u));
}

#[test]
fn test_into_inner_2() {
    let mut v = ArrayVec::<[String; 4]>::new();
    v.push("a".into());
    v.push("b".into());
    v.push("c".into());
    v.push("d".into());
    assert_eq!(v.into_inner().unwrap(), ["a", "b", "c", "d"]);
}

#[test]
fn test_into_inner_3_() {
    let mut v = ArrayVec::<[i32; 4]>::new();
    v.extend(1..);
    assert_eq!(v.into_inner().unwrap(), [1, 2, 3, 4]);
}

#[test]
fn test_write() {
    use std::io::Write;
    let mut v = ArrayVec::<[_; 8]>::new();
    write!(&mut v, "\x01\x02\x03").unwrap();
    assert_eq!(&v[..], &[1, 2, 3]);
    let r = v.write(&[9; 16]).unwrap();
    assert_eq!(r, 5);
    assert_eq!(&v[..], &[1, 2, 3, 9, 9, 9, 9, 9]);
}

#[test]
fn array_clone_from() {
    let mut v = ArrayVec::<[_; 4]>::new();
    v.push(vec![1, 2]);
    v.push(vec![3, 4, 5]);
    v.push(vec![6]);
    let reference = v.to_vec();
    let mut u = ArrayVec::<[_; 4]>::new();
    u.clone_from(&v);
    assert_eq!(&u, &reference[..]);

    let mut t = ArrayVec::<[_; 4]>::new();
    t.push(vec![97]);
    t.push(vec![]);
    t.push(vec![5, 6, 2]);
    t.push(vec![2]);
    t.clone_from(&v);
    assert_eq!(&t, &reference[..]);
    t.clear();
    t.clone_from(&v);
    assert_eq!(&t, &reference[..]);
}

#[test]
fn test_string() {
    use std::error::Error;

    let text = "hello world";
    let mut s = ArrayString::<[_; 16]>::new();
    s.push_str(text).unwrap();
    assert_eq!(&s, text);
    assert_eq!(text, &s);

    // Make sure Hash / Eq / Borrow match up so we can use HashMap
    let mut map = HashMap::new();
    map.insert(s, 1);
    assert_eq!(map[text], 1);

    let mut t = ArrayString::<[_; 2]>::new();
    assert!(t.push_str(text).is_err());
    assert_eq!(&t, "");

    t.push_str("ab").unwrap();
    // DerefMut
    let tmut: &mut str = &mut t;
    assert_eq!(tmut, "ab");

    // Test Error trait / try
    let t = || -> Result<(), Box<Error>> {
        let mut t = ArrayString::<[_; 2]>::new();
        try!(t.push_str(text));
        Ok(())
    }();
    assert!(t.is_err());
}

#[test]
fn test_string_from() {
    let text = "hello world";
	// Test `from` constructor
    let u = ArrayString::<[_; 11]>::from(text).unwrap();
    assert_eq!(&u, text);
    assert_eq!(u.len(), text.len());
}

#[test]
fn test_string_from_bytes() {
    let text = "hello world";
    let u = ArrayString::from_byte_string(b"hello world").unwrap();
    assert_eq!(&u, text);
    assert_eq!(u.len(), text.len());
}

#[test]
fn test_string_clone() {
    let text = "hi";
    let mut s = ArrayString::<[_; 4]>::new();
    s.push_str("abcd").unwrap();
    let t = ArrayString::<[_; 4]>::from(text).unwrap();
    s.clone_from(&t);
    assert_eq!(&t, &s);
}

#[test]
fn test_string_push() {
    let text = "abcαβγ";
    let mut s = ArrayString::<[_; 8]>::new();
    for c in text.chars() {
        if let Err(_) = s.push(c) {
            break;
        }
    }
    assert_eq!("abcαβ", &s[..]);
    s.push('x').ok();
    assert_eq!("abcαβx", &s[..]);
    assert!(s.push('x').is_err());
}


#[test]
fn test_insert_at_length() {
    let mut v = ArrayVec::<[_; 8]>::new();
    let result1 = v.insert(0, "a");
    let result2 = v.insert(1, "b");
    assert!(result1.is_none() && result2.is_none());
    assert_eq!(&v[..], &["a", "b"]);
}

#[test]
fn test_insert_out_of_bounds() {
    let mut v = ArrayVec::<[_; 8]>::new();
    let result = v.insert(1, "test");
    assert_eq!(result, Some("test"));
    assert_eq!(v.len(), 0);

    let mut u = ArrayVec::from([1, 2, 3, 4]);
    let ret = u.insert(3, 99);
    assert_eq!(&u[..], &[1, 2, 3, 99]);
    assert_eq!(ret, Some(4));
    let ret = u.insert(4, 77);
    assert_eq!(&u[..], &[1, 2, 3, 99]);
    assert_eq!(ret, Some(77));
}

#[test]
fn test_drop_in_insert() {
    use std::cell::Cell;

    let flag = &Cell::new(0);

    struct Bump<'a>(&'a Cell<i32>);

    impl<'a> Drop for Bump<'a> {
        fn drop(&mut self) {
            let n = self.0.get();
            self.0.set(n + 1);
        }
    }

    flag.set(0);

    {
        let mut array = ArrayVec::<[_; 2]>::new();
        array.push(Bump(flag));
        array.insert(0, Bump(flag));
        assert_eq!(flag.get(), 0);
        let ret = array.insert(1, Bump(flag));
        assert_eq!(flag.get(), 0);
        assert!(ret.is_some());
        drop(ret);
        assert_eq!(flag.get(), 1);
    }
    assert_eq!(flag.get(), 3);
}