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diff --git a/shared/comm-lib/src/tools.rs b/shared/comm-lib/src/tools.rs
--- a/shared/comm-lib/src/tools.rs
+++ b/shared/comm-lib/src/tools.rs
@@ -74,6 +74,67 @@
}
}
+pub trait IntoChunks<T> {
+ /// Splits the vec into `num_chunks` chunks and returns an iterator
+ /// over these chunks. The chunks do not overlap.
+ ///
+ /// Chunks size is given by `ceil(vector_length / num_chunks)`.
+ /// If vector length is not divisible by `num_chunks`,
+ /// the last chunk will have less elements.
+ ///
+ /// If you're looking for chunks of given size, use [`chunks`] instead.
+ ///
+ /// # Panics
+ ///
+ /// Panics if `num_chunks` is 0.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use comm_lib::tools::IntoChunks;
+ ///
+ /// let items = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+ /// let mut iter = items.into_n_chunks(3);
+ /// assert_eq!(&iter.next().unwrap(), &[1, 2, 3, 4]);
+ /// assert_eq!(&iter.next().unwrap(), &[5, 6, 7, 8]);
+ /// assert_eq!(&iter.next().unwrap(), &[9, 10]);
+ /// assert!(iter.next().is_none());
+ /// ```
+ ///
+ /// [`chunks`]: slice::chunks
+ fn into_n_chunks(self, num_chunks: usize) -> impl Iterator<Item = Vec<T>>;
+}
+
+impl<T> IntoChunks<T> for Vec<T> {
+ fn into_n_chunks(self, num_chunks: usize) -> impl Iterator<Item = Vec<T>> {
+ struct ChunksIterator<I> {
+ pub slice: Vec<I>,
+ pub chunk_size: usize,
+ }
+ impl<I> Iterator for ChunksIterator<I> {
+ type Item = Vec<I>;
+ fn next(&mut self) -> Option<Vec<I>> {
+ let next_size = std::cmp::min(self.slice.len(), self.chunk_size);
+ if next_size == 0 {
+ None
+ } else {
+ let next_chunk = self.slice.drain(0..next_size).collect();
+ Some(next_chunk)
+ }
+ }
+ }
+
+ assert!(num_chunks > 0, "Number of chunks cannot be 0");
+ let len = self.len();
+ let rem = len % num_chunks;
+ let chunk_size = len / num_chunks + if rem > 0 { 1 } else { 0 };
+ ChunksIterator {
+ slice: self,
+ chunk_size,
+ }
+ }
+}
+
pub fn generate_random_string(
length: usize,
rng: &mut (impl Rng + CryptoRng),
@@ -128,6 +189,11 @@
fn empty_is_invalid() {
assert!(!is_valid_identifier(""));
}
+}
+
+#[cfg(test)]
+mod defer_tests {
+ use super::*;
#[test]
fn defer_runs() {
@@ -164,3 +230,50 @@
assert!(v)
}
}
+
+#[cfg(test)]
+mod vec_utils_tests {
+ use super::*;
+
+ #[test]
+ fn test_chunks_without_remainder() {
+ let items = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12];
+ let mut iter = items.into_n_chunks(3);
+ assert_eq!(&iter.next().unwrap(), &[1, 2, 3, 4]);
+ assert_eq!(&iter.next().unwrap(), &[5, 6, 7, 8]);
+ assert_eq!(&iter.next().unwrap(), &[9, 10, 11, 12]);
+ assert!(iter.next().is_none());
+ }
+
+ #[test]
+ fn test_chunks_with_remainder() {
+ let items = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+ let mut iter = items.into_n_chunks(3);
+ assert_eq!(&iter.next().unwrap(), &[1, 2, 3, 4]);
+ assert_eq!(&iter.next().unwrap(), &[5, 6, 7, 8]);
+ assert_eq!(&iter.next().unwrap(), &[9, 10]);
+ assert!(iter.next().is_none());
+ }
+
+ #[test]
+ fn test_one_chunk() {
+ let items: Vec<i32> = vec![1, 2, 3];
+ let mut iter = items.into_n_chunks(1);
+ assert_eq!(&iter.next().unwrap(), &[1, 2, 3]);
+ assert!(iter.next().is_none());
+ }
+
+ #[test]
+ fn test_empty_vec() {
+ let items: Vec<i32> = vec![];
+ let mut iter = items.into_n_chunks(2);
+ assert!(iter.next().is_none());
+ }
+
+ #[test]
+ #[should_panic]
+ fn into_n_chunks_panics_with_0_chunks() {
+ let items = vec![1, 2, 3];
+ let _ = items.into_n_chunks(0);
+ }
+}

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