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|
use itertools::Itertools;
use pathfinding::undirected::connected_components::*;
use rand::prelude::*;
use rand_xorshift::XorShiftRng;
use std::collections::HashSet;
#[test]
fn basic_separate_components() {
let groups = [vec![1, 2], vec![3, 4], vec![5, 6], vec![1, 4]];
let (h, g) = separate_components(&groups);
assert!([1, 2, 3, 4].iter().map(|n| h[n]).all_equal());
assert_eq!(h[&5], h[&6]);
assert!(h[&1] != h[&5]);
assert_eq!(h.len(), 6);
assert_eq!(g[0], g[1]);
assert_eq!(g[0], g[3]);
assert!(g[0] != g[2]);
assert_eq!(g.len(), 4);
}
#[test]
fn empty_separate_components() {
let groups = [vec![1, 2], vec![3, 4], vec![], vec![1, 4]];
let (h, g) = separate_components(&groups);
assert!([1, 2, 3, 4].iter().map(|n| h[n]).all_equal());
assert_eq!(h.len(), 4);
assert_eq!(g[0], g[1]);
assert_eq!(g[0], g[3]);
assert!(g[0] != g[2]);
assert_eq!(g[2], usize::MAX);
assert_eq!(g.len(), 4);
}
#[test]
fn basic_components() {
let mut c = components(&[vec![1, 2], vec![3, 4], vec![5, 6], vec![1, 4, 7]]);
c.sort_unstable_by_key(|v| *v.iter().min().unwrap());
assert_eq!(c.len(), 2);
assert_eq!(
c[0].clone().into_iter().sorted().collect_vec(),
vec![1, 2, 3, 4, 7]
);
assert_eq!(c[1].clone().into_iter().sorted().collect_vec(), vec![5, 6]);
}
#[test]
fn empty_components() {
let mut c = components(&[vec![1, 2], vec![3, 4], vec![], vec![1, 4, 7]]);
c.sort_unstable_by_key(|v| *v.iter().min().unwrap());
assert_eq!(c.len(), 1);
assert_eq!(
c[0].clone().into_iter().sorted().collect_vec(),
vec![1, 2, 3, 4, 7]
);
}
#[test]
fn basic_connected_components() {
let mut counter = 0;
let mut c = connected_components(&[1, 4], |&n| {
counter += 1;
if n % 2 == 0 {
vec![2, 4, 6, 8]
} else {
vec![1, 3, 5, 7]
}
});
c.sort_unstable_by_key(|v| *v.iter().min().unwrap());
assert_eq!(c.len(), 2);
assert_eq!(
c[0].clone().into_iter().sorted().collect_vec(),
vec![1, 3, 5, 7]
);
assert_eq!(
c[1].clone().into_iter().sorted().collect_vec(),
vec![2, 4, 6, 8]
);
assert_eq!(counter, 2);
}
#[test]
fn larger_separate_components() {
// Create 100 groups of 100 elements, then randomly split
// into sub-groups.
let mut rng = XorShiftRng::from_seed([
3, 42, 93, 129, 1, 85, 72, 42, 84, 23, 95, 212, 253, 10, 4, 2,
]);
let mut seen = HashSet::new();
let mut components = (0..100)
.map(|_| {
let mut component = Vec::new();
for _ in 0..100 {
let node = rng.next_u64();
if !seen.contains(&node) {
seen.insert(node);
component.push(node);
}
}
component.sort_unstable();
assert!(
!component.is_empty(),
"component is empty, rng seed needs changing"
);
component
})
.collect_vec();
components.sort_unstable_by_key(|v| *v.iter().min().unwrap());
let mut groups = components
.iter()
.flat_map(|component| {
let mut component = component.clone();
component.shuffle(&mut rng);
let mut subcomponents = Vec::new();
while !component.is_empty() {
let cut = rng.gen_range(0..component.len());
let mut subcomponent = component.drain(cut..).collect_vec();
if !component.is_empty() {
subcomponent.push(component[0]);
}
subcomponent.shuffle(&mut rng);
subcomponents.push(subcomponent);
}
subcomponents
})
.collect_vec();
groups.shuffle(&mut rng);
let (_, group_mappings) = separate_components(&groups);
let mut out_groups = vec![HashSet::new(); groups.len()];
for (i, n) in group_mappings.into_iter().enumerate() {
assert!(
n < groups.len(),
"group index is greater than expected: {}/{}",
n,
groups.len()
);
for e in &groups[i] {
out_groups[n].insert(*e);
}
}
let out_groups = out_groups
.into_iter()
.map(|g| g.into_iter().collect_vec())
.collect_vec();
let mut out_groups = out_groups
.into_iter()
.filter_map(|mut group| {
if group.is_empty() {
None
} else {
group.sort_unstable();
Some(group)
}
})
.collect_vec();
out_groups.sort_by_key(|c| c[0]);
assert_eq!(out_groups, components);
}
|
