[Merged by Bors] - Added resource_id and changed init_resource and init_non_send_resource to return ComponentId

crates/bevy_ecs/src/component.rs

@@ -498,13 +498,39 @@ impl Components {
  self.get_id(TypeId::of::<T>())
  }
 
+ /// Type-erased equivalent of [`Components::resource_id`].
  #[inline]
  pub fn get_resource_id(&self, type_id: TypeId) -> Option<ComponentId> {
  self.resource_indices
  .get(&type_id)
  .map(|index| ComponentId(*index))
  }
 
+ /// Returns the [`ComponentId`] of the given [`Resource`] type `T`.
+ ///
+ /// The returned `ComponentId` is specific to the `Components instance`
+ /// it was retrieved from and should not be used with another `Components`
+ /// instance.
+ ///
+ /// Returns [`None`] if the `Resource` type has not
+ /// yet been initialized using [`Components::init_resource`].
+ ///
+ /// ```rust
+ /// use bevy_ecs::prelude::*;
+ ///
+ /// let mut world = World::new();
+ ///
+ /// #[derive(Resource)]
+ /// struct ResourceA;
+ ///
+ /// let resource_a_id = world.init_resource::<ResourceA>();
+ ///
+ /// assert_eq!(resource_a_id, world.components().resource_id::<ResourceA>().unwrap())
+ /// ```
+ pub fn resource_id<T: Resource>(&self) -> Option<ComponentId> {
+ self.get_resource_id(TypeId::of::<T>())
+ }
+
  #[inline]
  pub fn init_resource<T: Resource>(&mut self) -> ComponentId {
  // SAFETY: The [`ComponentDescriptor`] matches the [`TypeId`]