Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Fixes to underflowing / wrapping in Rust version Lazy Stable Sort #8

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open

Fixes to underflowing / wrapping in Rust version Lazy Stable Sort #8

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
49 changes: 44 additions & 5 deletions Rust/src/grailsort.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1398,9 +1398,9 @@ fn grail_lazy_stable_sort<T: Sortable, F: FnMut(&T, &T) -> Ordering>(
let mut merge_len = 2;
while merge_len < length {
let mut merge_index = 0;
let merge_end = length - (2 * merge_len);
let merge_end: isize = length as isize - (2 * merge_len) as isize;

while merge_index <= merge_end {
while merge_index as isize <= merge_end {
grail_lazy_merge(set, start + merge_index, merge_len, merge_len, cmp);
merge_index += 2 * merge_len;
}
Expand All @@ -1415,7 +1415,7 @@ fn grail_lazy_stable_sort<T: Sortable, F: FnMut(&T, &T) -> Ordering>(
cmp,
);
}

merge_len *= 2;
}
}
Expand Down Expand Up @@ -1604,7 +1604,7 @@ mod private_tests {

#[test]
fn build_blocks_random_sizes_random_values() {
for _ in 0..100 {
for _ in 0..500 {
let mut rng = thread_rng();
let len = rng.gen_range(2, 262144);
let mut set: Vec<GrailPair> = (0..len)
Expand Down Expand Up @@ -1643,7 +1643,7 @@ mod private_tests {
};
let mut cursor = buffer_end + 1;
while cursor < len {
if (cursor - buffer_end) % subarray_len != 0 {
if subarray_len != 0 && (cursor - buffer_end) % subarray_len != 0 {
assert!(
set[cursor] >= set[cursor - 1],
"Built Fragment Out Of Order: {:?}, {:?}, ({}, {})",
Expand Down Expand Up @@ -1755,6 +1755,45 @@ mod private_tests {
}
}


//These tests are here instead of tests.rs, as grail_lazy_stable_sort is internal
#[test]
fn lazy_stable_sort_many_unique() {
for _ in 0..12 {
let mut rng = thread_rng();
let len = rng.gen_range(17, 64);
let mut set: Vec<GrailPair> = (0..len)
.map(|x| GrailPair {
key: rng.gen_range(0, len as isize),
value: x as isize,
})
.collect();
grail_lazy_stable_sort(&mut set, 0, len, &mut |a: &GrailPair, b: &GrailPair| {
a.key.cmp(&b.key)
});
verify_sort(&set);
}
}
#[test]
fn lazy_stable_sort_few_unique() {
for _ in 0..12 {
let mut rng = thread_rng();
let len = rng.gen_range(17, 524288);
let baseline = rng.gen_range(1,256);
let mut set: Vec<GrailPair> = (0..len)
.map(|x| GrailPair {
key: rng.gen_range(baseline, baseline + 3 as isize),
value: x as isize,
})
.collect();
grail_lazy_stable_sort(&mut set, 0, len, &mut |a: &GrailPair, b: &GrailPair| {
a.key.cmp(&b.key)
});
verify_sort(&set);
}
}


//NOTE: There is no test for the final grail_lazy_merge call,
//as verifying such is equivalent to verifying the actual sort, which every other test does.

Expand Down