Make builder types take and return Self

crates/bevy_ecs/src/storage/table.rs

@@ -526,13 +526,16 @@ impl TableBuilder {
  }
  }
 
- pub fn add_column(&mut self, component_info: &ComponentInfo) {
+ #[must_use]
+ pub fn add_column(mut self, component_info: &ComponentInfo) -> Self {
  self.columns.insert(
  component_info.id(),
  Column::with_capacity(component_info, self.capacity),
  );
+ self
  }
 
+ #[must_use]
  pub fn build(self) -> Table {
  Table {
  columns: self.columns.into_immutable(),
@@ -865,7 +868,7 @@ impl Tables {
  .or_insert_with(|| {
  let mut table = TableBuilder::with_capacity(0, component_ids.len());
  for component_id in component_ids {
- table.add_column(components.get_info_unchecked(*component_id));
+ table = table.add_column(components.get_info_unchecked(*component_id));
  }
  tables.push(table.build());
  (component_ids.to_vec(), TableId::new(tables.len() - 1))
@@ -929,9 +932,9 @@ mod tests {
  let mut storages = Storages::default();
  let component_id = components.init_component::<W<TableRow>>(&mut storages);
  let columns = &[component_id];
- let mut builder = TableBuilder::with_capacity(0, columns.len());
- builder.add_column(components.get_info(component_id).unwrap());
- let mut table = builder.build();
+ let mut table = TableBuilder::with_capacity(0, columns.len())
+  .add_column(components.get_info(component_id).unwrap())
+  .build();
  let entities = (0..200).map(Entity::from_raw).collect::<Vec<_>>();
  for entity in &entities {
  // SAFETY: we allocate and immediately set data afterwards

crates/bevy_scene/src/dynamic_scene.rs

@@ -51,12 +51,10 @@ impl DynamicScene {
 
  /// Create a new dynamic scene from a given world.
  pub fn from_world(world: &World) -> Self {
- let mut builder = DynamicSceneBuilder::from_world(world);
-
- builder.extract_entities(world.iter_entities().map(|entity| entity.id()));
- builder.extract_resources();
-
- builder.build()
+ DynamicSceneBuilder::from_world(world)
+ .extract_entities(world.iter_entities().map(|entity| entity.id()))
+ .extract_resources()
+ .build()
  }
 
  /// Write the resources, the dynamic entities, and their corresponding components to the given world.
@@ -210,10 +208,10 @@ mod tests {
 
  // We then write this relationship to a new scene, and then write that scene back to the
  // world to create another parent and child relationship
- let mut scene_builder = DynamicSceneBuilder::from_world(&world);
- scene_builder.extract_entity(original_parent_entity);
- scene_builder.extract_entity(original_child_entity);
- let scene = scene_builder.build();
+ let scene = DynamicSceneBuilder::from_world(&world)
+  .extract_entity(original_parent_entity)
+  .extract_entity(original_child_entity)
+  .build();
  let mut entity_map = HashMap::default();
  scene.write_to_world(&mut world, &mut entity_map).unwrap();