Add try_get_* component accessors to filtered entity references and mutators
#21588
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alice-i-cecile
added
A-ECS
| if !self.access.has_component_write(component_id) { | ||
| return None; | ||
| } | ||
| self.entity.get_mut_by_id(component_id).ok() |
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Looks like this is just a formatting change? the compiler allows calling get_mut_by_id without the unsafe block here because bevy_ecs doesn't use unsafe_op_in_unsafe_fn, but it's good style to annotate unsafe function calls even within unsafe functions, since not all of the safety bounds of the parent function may have to hold for the inner call.
| pub fn try_get<T: Component>(&self) -> Result<&'w T, ComponentFetchError> { | ||
| let components = self.entity.world().components(); | ||
| let id = components.get_valid_id(TypeId::of::<T>()).ok_or( | ||
| ComponentFetchError::ComponentNotFound(ComponentId::new(usize::MAX)), |
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We might want to differentiate between ComponentNotFound on the entity and ComponentNotRegistered
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I agree, this would be a confusing error to get.
| /// Returns an error distinguishing between insufficient access and the component | ||
| /// not being present on the entity. | ||
| #[inline] | ||
| pub fn try_get_mut<T: Component<Mutability = Mutable>>( |
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not blocking, but: an unchecked version of this method as well as try_get_mut_by_id sounds useful to me as well.
| pub fn try_get<T: Component>(&self) -> Result<&'w T, ComponentFetchError> { | ||
| let components = self.entity.world().components(); | ||
| let id = components.get_valid_id(TypeId::of::<T>()).ok_or( | ||
| ComponentFetchError::ComponentNotFound(ComponentId::new(usize::MAX)), |
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I agree, this would be a confusing error to get.
4 participants
Objective
Fixes #21403
Solution
try_get_*APIs to filtered entity refs/muts to returnResult, distinguishing missing components from insufficient access.ComponentFetchErrorwithInsufficientAccessandComponentNotFound.get/get_refthatNonecan also mean no read access under filtering.Testing
cargo test -p bevy_ecs.