Double the capacity when BlobVec is full

crates/bevy_ecs/src/storage/blob_vec.rs

@@ -230,7 +230,9 @@ impl BlobVec {
     /// The `value` must match the [`layout`](`BlobVec::layout`) of the elements in the [`BlobVec`].
     #[inline]
     pub unsafe fn push(&mut self, value: OwningPtr<'_>) {
-        self.reserve_exact(1);
+        if self.len == self.capacity {
+            self.reserve_exact(self.capacity.max(1));
+        }
         let index = self.len;
         self.len += 1;
         self.initialize_unchecked(index, value);
@@ -519,7 +521,7 @@ mod tests {
         }
 
         assert_eq!(blob_vec.len(), 1_000);
-        assert_eq!(blob_vec.capacity(), 1_000);
+        assert_eq!(blob_vec.capacity(), 1_024);
     }
 
     #[derive(Debug, Eq, PartialEq, Clone)]
@@ -579,19 +581,19 @@ mod tests {
 
                 push(&mut blob_vec, foo3.clone());
                 assert_eq!(blob_vec.len(), 3);
-                assert_eq!(blob_vec.capacity(), 3);
+                assert_eq!(blob_vec.capacity(), 4);
 
                 let last_index = blob_vec.len() - 1;
                 let value = swap_remove::<Foo>(&mut blob_vec, last_index);
                 assert_eq!(foo3, value);
 
                 assert_eq!(blob_vec.len(), 2);
-                assert_eq!(blob_vec.capacity(), 3);
+                assert_eq!(blob_vec.capacity(), 4);
 
                 let value = swap_remove::<Foo>(&mut blob_vec, 0);
                 assert_eq!(foo1, value);
                 assert_eq!(blob_vec.len(), 1);
-                assert_eq!(blob_vec.capacity(), 3);
+                assert_eq!(blob_vec.capacity(), 4);
 
                 foo2.a = 8;
                 assert_eq!(get_mut::<Foo>(&mut blob_vec, 0), &foo2);