# Objective
While working on #18058 I realized I could use
`RelationshipTargetCollection::new`, so I added it.
## Solution
- Add `RelationshipTargetCollection::new`
- Add `RelationshipTargetCollection::reserve`. Could generally be useful
when doing micro-optimizations.
- Add `RelationshipTargetCollection::shrink_to_fit`. Rust collections
generally don't shrink when removing elements. Might be a good idea to
call this once in a while.
## Testing
`cargo clippy`
---
## Showcase
`RelationshipSourceCollection` now implements `new`, `reserve` and
`shrink_to_fit` to give greater control over how much memory it
consumes.
## Migration Guide
Any type implementing `RelationshipSourceCollection` now needs to also
implement `new`, `reserve` and `shrink_to_fit`. `reserve` and
`shrink_to_fit` can be made no-ops if they conceptually mean nothing to
a collection.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Chris Russell <8494645+chescock@users.noreply.github.com>
0f446d49a1