Convenience method for entity naming (#7186)

# Objective
- Trying to make it easier to have a more user friendly debugging name for when you want to print out an entity.

## Solution
- Add a new `WorldQuery` struct `DebugName` to format the `Name` if the entity has one, otherwise formats the `Entity` id.
This means we can do this and get more descriptive errors without much more effort:
```rust
fn my_system(moving: Query<(DebugName, &mut Position, &Velocity)>) {
    for (name, mut position, velocity) in &mut moving {
        position += velocity; 
        if position.is_nan() {
            error!("{:?} has an invalid position state", name);
        }
    }
}
```

---

## Changelog
- Added `DebugName` world query for more human friendly debug names of entities.
This commit is contained in:
Aceeri 2023-01-30 20:50:46 +00:00
parent ca2d91e7ab
commit 937fc039b1
2 changed files with 38 additions and 2 deletions

View file

@ -15,7 +15,7 @@ pub mod prelude {
//! The Bevy Core Prelude.
#[doc(hidden)]
pub use crate::{
FrameCountPlugin, Name, TaskPoolOptions, TaskPoolPlugin, TypeRegistrationPlugin,
DebugName, FrameCountPlugin, Name, TaskPoolOptions, TaskPoolPlugin, TypeRegistrationPlugin,
};
}

View file

@ -1,4 +1,6 @@
use bevy_ecs::{component::Component, reflect::ReflectComponent};
use bevy_ecs::{
component::Component, entity::Entity, query::WorldQuery, reflect::ReflectComponent,
};
use bevy_reflect::Reflect;
use bevy_reflect::{std_traits::ReflectDefault, FromReflect};
use bevy_utils::AHasher;
@ -77,6 +79,40 @@ impl std::fmt::Display for Name {
}
}
/// Convenient query for giving a human friendly name to an entity.
///
/// ```rust
/// # use bevy_core::prelude::*;
/// # use bevy_ecs::prelude::*;
/// # #[derive(Component)] pub struct Score(f32);
/// fn increment_score(mut scores: Query<(DebugName, &mut Score)>) {
/// for (name, mut score) in &mut scores {
/// score.0 += 1.0;
/// if score.0.is_nan() {
/// bevy_utils::tracing::error!("Score for {:?} is invalid", name);
/// }
/// }
/// }
/// # bevy_ecs::system::assert_is_system(increment_score);
/// ```
#[derive(WorldQuery)]
pub struct DebugName {
/// A [`Name`] that the entity might have that is displayed if available.
pub name: Option<&'static Name>,
/// The unique identifier of the entity as a fallback.
pub entity: Entity,
}
impl<'a> std::fmt::Debug for DebugNameItem<'a> {
#[inline(always)]
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
match self.name {
Some(name) => write!(f, "{:?} ({:?})", &name, &self.entity),
None => std::fmt::Debug::fmt(&self.entity, f),
}
}
}
/* Conversions from strings */
impl From<&str> for Name {