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use std::{
hash::Hash,
ops::{Index, IndexMut},
};
use stable_id_traits::Successor;
use super::SparseEntities;
impl<DataT, IndexT> SparseEntities<DataT, IndexT>
where
IndexT: Successor + Clone + Copy + Hash + Eq + Default,
{
pub fn len(&self) -> usize {
self.data.len()
}
pub fn is_empty(&self) -> bool {
self.data.is_empty()
}
pub fn get(&self, index: IndexT) -> Option<&DataT> {
self.data.get(&index)
}
pub fn get_mut(&mut self, index: IndexT) -> Option<&mut DataT> {
self.data.get_mut(&index)
}
pub fn remove(&mut self, index: IndexT) -> DataT {
self.data.remove(&index).expect("id is not value")
}
pub fn alloc(&mut self, data: DataT) -> IndexT {
let next_id = self.seq.next_value();
self.data.insert(next_id, data);
next_id
}
pub fn iter(&self) -> impl Iterator<Item = (IndexT, &DataT)> {
self.data
.iter()
.map(|(virtual_id, data)| (*virtual_id, data))
}
pub fn iter_mut(&mut self) -> impl Iterator<Item = (IndexT, &mut DataT)> {
self.data
.iter_mut()
.map(|(virtual_id, data)| (*virtual_id, data))
}
}
impl<DataT, IndexT> IntoIterator for SparseEntities<DataT, IndexT>
where
IndexT: Successor + Clone + Copy + Default + Hash + Eq,
{
type Item = (IndexT, DataT);
type IntoIter = std::collections::hash_map::IntoIter<IndexT, DataT>;
fn into_iter(self) -> Self::IntoIter {
self.data.into_iter()
}
}
impl<DataT, IndexT> Default for SparseEntities<DataT, IndexT>
where
IndexT: Default,
{
fn default() -> Self {
Self {
data: Default::default(),
seq: Default::default(),
}
}
}
impl<DataT, IndexT> Index<IndexT> for SparseEntities<DataT, IndexT>
where
IndexT: Successor + Clone + Copy + Hash + Eq + Default,
{
type Output = DataT;
fn index(&self, index: IndexT) -> &Self::Output {
self.get(index).expect("element not exist")
}
}
impl<DataT, IndexT> IndexMut<IndexT> for SparseEntities<DataT, IndexT>
where
IndexT: Successor + Clone + Copy + Hash + Eq + Default,
{
fn index_mut(&mut self, index: IndexT) -> &mut Self::Output {
self.get_mut(index).expect("element not exist")
}
}
#[cfg(test)]
mod tests {
use std::collections::HashMap;
use crate::SparseEntities;
#[test]
fn access_out_of_bound() {
let mut entities = SparseEntities::default();
entities.alloc(1232);
assert_eq!(entities.get(312u16), None);
}
#[test]
#[should_panic(expected = "element not exist")]
fn access_out_of_bound_mut() {
let mut entities = SparseEntities::default();
entities.alloc(1232);
entities[312u16] = 3333;
}
#[test]
fn normal() {
let mut entities = SparseEntities::default();
fn check_all(entities: &SparseEntities<&str>) {
entities
.iter()
.for_each(|(id, data)| assert_eq!(entities[id], *data));
}
vec!["1", "2", "3", "4", "5"]
.into_iter()
.fold(HashMap::new(), |mut acc, data| {
acc.insert(entities.alloc(data), data);
acc
})
.into_iter()
.for_each(|(id, data)| assert_eq!(entities[id], data));
entities.remove(1);
check_all(&entities);
entities.remove(4);
check_all(&entities);
entities.remove(3);
check_all(&entities);
entities.remove(2);
assert_eq!(entities.len(), 1);
check_all(&entities);
entities.remove(0);
assert!(entities.is_empty());
check_all(&entities);
}
}