use rand::rngs::SmallRng;
use rand::{RngExt, SeedableRng};
use sux::prelude::*;
macro_rules! test {
($NUM_U32S: literal; $COUNTER_WIDTH: literal) => {
use sux::traits::Select;
let mut rng = SmallRng::seed_from_u64(0);
let density = 0.5;
let lens = (1..1000)
.chain((1000..10000).step_by(100))
.chain([1 << 20, 1 << 24]);
for len in lens {
let bits = (0..len)
.map(|_| rng.random_bool(density))
.collect::<BitVec>();
let rank_small_sel =
SelectSmall::<$NUM_U32S, $COUNTER_WIDTH, _>::new(RankSmall::<
$NUM_U32S,
$COUNTER_WIDTH,
_,
>::new(bits.clone()));
let ones = bits.count_ones();
let mut pos = Vec::with_capacity(ones);
for i in 0..len {
if bits[i] {
pos.push(i);
}
}
for (i, &p) in pos.iter().enumerate() {
assert_eq!(rank_small_sel.select(i), Some(p));
}
assert_eq!(rank_small_sel.select(ones + 1), None);
}
};
}
#[test]
fn test_rank_small0() {
test!(2; 9);
}
#[test]
fn test_rank_small1() {
test!(1; 9);
}
#[test]
fn test_rank_small2() {
test!(1; 10);
}
#[test]
fn test_rank_small3() {
test!(1; 11);
}
#[test]
fn test_rank_small4() {
test!(3; 13);
}
#[test]
fn test_empty() {
let bits = BitVec::new(0);
let select = SelectSmall::<2, 9, _>::new(RankSmall::<2, 9>::new(bits.clone()));
assert_eq!(select.count_ones(), 0);
assert_eq!(select.len(), 0);
assert_eq!(select.select(0), None);
let inner = select.into_inner();
assert_eq!(inner.len(), 0);
let inner = inner.into_inner();
assert_eq!(inner.len(), 0);
}
#[test]
fn test_ones() {
let len = 300_000;
let bits = (0..len).map(|_| true).collect::<BitVec>();
let select = SelectSmall::<2, 9, _>::new(RankSmall::<2, 9>::new(bits));
assert_eq!(select.count_ones(), len);
assert_eq!(select.len(), len);
for i in 0..len {
assert_eq!(select.select(i), Some(i));
}
}
#[test]
fn test_zeros() {
let len = 300_000;
let bits = (0..len).map(|_| false).collect::<BitVec>();
let select = SelectSmall::<2, 9, _>::new(RankSmall::<2, 9>::new(bits));
assert_eq!(select.count_ones(), 0);
assert_eq!(select.len(), len);
assert_eq!(select.select(0), None);
}
#[test]
fn test_few_ones() {
let lens = [1 << 18, 1 << 19, 1 << 20];
for len in lens {
for num_ones in [1, 2, 4, 8, 16, 32, 64, 128] {
let bits = (0..len)
.map(|i| i % (len / num_ones) == 0)
.collect::<BitVec>();
let select = SelectSmall::<2, 9, _>::new(RankSmall::<2, 9>::new(bits));
assert_eq!(select.count_ones(), num_ones);
assert_eq!(select.len(), len);
for i in 0..num_ones {
assert_eq!(select.select(i), Some(i * (len / num_ones)));
}
}
}
}
#[test]
fn test_non_uniform() {
let lens = [1 << 18, 1 << 19, 1 << 20];
let mut rng = SmallRng::seed_from_u64(0);
for len in lens {
for density in [0.5] {
let density0 = density * 0.01;
let density1 = density * 0.99;
let len1;
let len2;
if len % 2 != 0 {
len1 = len / 2 + 1;
len2 = len / 2;
} else {
len1 = len / 2;
len2 = len / 2;
}
let first_half = loop {
let b = (0..len1)
.map(|_| rng.random_bool(density0))
.collect::<BitVec>();
if b.count_ones() > 0 {
break b;
}
};
let num_ones_first_half = first_half.count_ones();
let second_half = (0..len2)
.map(|_| rng.random_bool(density1))
.collect::<BitVec>();
let num_ones_second_half = second_half.count_ones();
assert!(num_ones_first_half > 0);
assert!(num_ones_second_half > 0);
let bits = first_half
.into_iter()
.chain(second_half.into_iter())
.collect::<BitVec>();
assert_eq!(
num_ones_first_half + num_ones_second_half,
bits.count_ones()
);
assert_eq!(bits.len(), len as usize);
let ones = bits.count_ones();
let mut pos = Vec::with_capacity(ones);
for i in 0..(len as usize) {
if bits[i] {
pos.push(i);
}
}
let select = SelectSmall::<2, 9, _>::new(RankSmall::<2, 9>::new(bits));
for (i, &p) in pos.iter().enumerate() {
assert_eq!(select.select(i), Some(p));
}
assert_eq!(select.select(ones + 1), None);
}
}
}
#[test]
fn test_extremely_sparse() {
let len = 1 << 18;
let bits = (0..len / 2)
.map(|_| false)
.chain([true])
.chain((0..1 << 17).map(|_| false))
.chain([true, true])
.chain((0..1 << 18).map(|_| false))
.chain([true])
.chain((0..len / 2).map(|_| false))
.collect::<BitVec>();
let select = SelectSmall::<2, 9, _>::new(RankSmall::<2, 9>::new(bits));
assert_eq!(select.count_ones(), 4);
assert_eq!(select.select(0), Some(len / 2));
assert_eq!(select.select(1), Some(len / 2 + (1 << 17) + 1));
assert_eq!(select.select(2), Some(len / 2 + (1 << 17) + 2));
}
#[cfg(feature = "slow_tests")]
#[test]
fn test_extremely_sparse_and_large() {
let num_words = 3 * (1 << 26) + 1;
let len = num_words * 64;
let mut data: Vec<usize> = Vec::with_capacity(num_words);
data.push(1);
data.extend(std::iter::repeat_n(0, (1 << 26) - 2));
data.push(1 << 63);
data.extend(std::iter::repeat_n(0, 1 << 27));
data.push(1);
assert_eq!(data.len(), num_words);
let bits = unsafe { BitVec::from_raw_parts(data, len) };
let rank_small = RankSmall::<2, 9>::new(bits);
let select = SelectSmall::<2, 9, _>::new(rank_small);
assert_eq!(select.count_ones(), 3);
assert_eq!(select.select(0), Some(0));
assert_eq!(select.select(1), Some((1 << 32) - 1));
assert_eq!(select.select(2), Some(3 * (1 << 32)));
assert_eq!(select.select(3), None);
}
#[allow(unused_macros)]
macro_rules! test_large {
($NUM_U32S: literal; $COUNTER_WIDTH: literal) => {
const ONES_STEP_4: usize = 1usize << 0
| 1 << 4
| 1 << 8
| 1 << 12
| 1 << 16
| 1 << 20
| 1 << 24
| 1 << 28
| 1 << 32
| 1 << 36
| 1 << 40
| 1 << 44
| 1 << 48
| 1 << 52
| 1 << 56
| 1 << 60;
let len = 3 * (1 << 32) + 64 * 1000;
let num_words = len / 64;
let mut data: Vec<usize> = Vec::with_capacity(num_words);
for _ in 0..num_words {
data.push(ONES_STEP_4);
}
let bits = unsafe { BitVec::from_raw_parts(data, len) };
let rank_small = RankSmall::<$NUM_U32S, $COUNTER_WIDTH>::new(bits);
let select = SelectSmall::<$NUM_U32S, $COUNTER_WIDTH, _>::new(rank_small);
for i in (0..len).step_by(4) {
assert_eq!(select.select(i / 4), Some(i));
}
};
}
#[cfg(feature = "slow_tests")]
#[test]
fn test_large0() {
test_large!(2; 9);
}
#[cfg(feature = "slow_tests")]
#[test]
fn test_large1() {
test_large!(1; 9);
}
#[cfg(feature = "slow_tests")]
#[test]
fn test_large2() {
test_large!(1; 10);
}
#[cfg(feature = "slow_tests")]
#[test]
fn test_large3() {
test_large!(1; 11);
}
#[cfg(feature = "slow_tests")]
#[test]
fn test_large4() {
test_large!(3; 13);
}