bevy/crates
Mark Wainwright f0a8994f55
Split WorldQuery into WorldQueryData and WorldQueryFilter (#9918)
# Objective

- Fixes #7680
- This is an updated for https://github.com/bevyengine/bevy/pull/8899
which had the same objective but fell a long way behind the latest
changes


## Solution

The traits `WorldQueryData : WorldQuery` and `WorldQueryFilter :
WorldQuery` have been added and some of the types and functions from
`WorldQuery` has been moved into them.

`ReadOnlyWorldQuery` has been replaced with `ReadOnlyWorldQueryData`. 

`WorldQueryFilter` is safe (as long as `WorldQuery` is implemented
safely).

`WorldQueryData` is unsafe - safely implementing it requires that
`Self::ReadOnly` is a readonly version of `Self` (this used to be a
safety requirement of `WorldQuery`)

The type parameters `Q` and `F` of `Query` must now implement
`WorldQueryData` and `WorldQueryFilter` respectively.

This makes it impossible to accidentally use a filter in the data
position or vice versa which was something that could lead to bugs.
~~Compile failure tests have been added to check this.~~

It was previously sometimes useful to use `Option<With<T>>` in the data
position. Use `Has<T>` instead in these cases.

The `WorldQuery` derive macro has been split into separate derive macros
for `WorldQueryData` and `WorldQueryFilter`.

Previously it was possible to derive both `WorldQuery` for a struct that
had a mixture of data and filter items. This would not work correctly in
some cases but could be a useful pattern in others. *This is no longer
possible.*

---

## Notes

- The changes outside of `bevy_ecs` are all changing type parameters to
the new types, updating the macro use, or replacing `Option<With<T>>`
with `Has<T>`.

- All `WorldQueryData` types always returned `true` for `IS_ARCHETYPAL`
so I moved it to `WorldQueryFilter` and
replaced all calls to it with `true`. That should be the only logic
change outside of the macro generation code.

- `Changed<T>` and `Added<T>` were being generated by a macro that I
have expanded. Happy to revert that if desired.

- The two derive macros share some functions for implementing
`WorldQuery` but the tidiest way I could find to implement them was to
give them a ton of arguments and ask clippy to ignore that.

## Changelog

### Changed
- Split `WorldQuery` into `WorldQueryData` and `WorldQueryFilter` which
now have separate derive macros. It is not possible to derive both for
the same type.
- `Query` now requires that the first type argument implements
`WorldQueryData` and the second implements `WorldQueryFilter`

## Migration Guide

- Update derives

```rust
// old
#[derive(WorldQuery)]
#[world_query(mutable, derive(Debug))]
struct CustomQuery {
    entity: Entity,
    a: &'static mut ComponentA
}

#[derive(WorldQuery)]
struct QueryFilter {
    _c: With<ComponentC>
}

// new 
#[derive(WorldQueryData)]
#[world_query_data(mutable, derive(Debug))]
struct CustomQuery {
    entity: Entity,
    a: &'static mut ComponentA,
}

#[derive(WorldQueryFilter)]
struct QueryFilter {
    _c: With<ComponentC>
}
```
- Replace `Option<With<T>>` with `Has<T>`

```rust
/// old
fn my_system(query: Query<(Entity, Option<With<ComponentA>>)>)
{
  for (entity, has_a_option) in query.iter(){
    let has_a:bool = has_a_option.is_some();
    //todo!()
  }
}

/// new
fn my_system(query: Query<(Entity, Has<ComponentA>)>)
{
  for (entity, has_a) in query.iter(){
    //todo!()
  }
}
```

- Fix queries which had filters in the data position or vice versa.

```rust
// old
fn my_system(query: Query<(Entity, With<ComponentA>)>)
{
  for (entity, _) in query.iter(){
  //todo!()
  }
}

// new
fn my_system(query: Query<Entity, With<ComponentA>>)
{
  for entity in query.iter(){
  //todo!()
  }
}

// old
fn my_system(query: Query<AnyOf<(&ComponentA, With<ComponentB>)>>)
{
  for (entity, _) in query.iter(){
  //todo!()
  }
}

// new
fn my_system(query: Query<Option<&ComponentA>, Or<(With<ComponentA>, With<ComponentB>)>>)
{
  for entity in query.iter(){
  //todo!()
  }
}

```

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2023-11-28 03:56:07 +00:00
..
bevy_a11y Add [lints] table, fix adding #![allow(clippy::type_complexity)] everywhere (#10011) 2023-11-18 20:58:48 +00:00
bevy_animation Enable clippy::undocumented_unsafe_blocks warning across the workspace (#10646) 2023-11-21 02:06:24 +00:00
bevy_app Wait until FixedUpdate can see events before dropping them (#10077) 2023-11-26 23:04:41 +00:00
bevy_asset Fix GLTF scene dependencies and make full scene renders predictable (#10745) 2023-11-27 22:42:28 +00:00
bevy_audio Standardize toml format with taplo (#10594) 2023-11-21 01:04:14 +00:00
bevy_core Split WorldQuery into WorldQueryData and WorldQueryFilter (#9918) 2023-11-28 03:56:07 +00:00
bevy_core_pipeline impl From<Color> for ClearColorConfig (#10734) 2023-11-26 20:48:03 +00:00
bevy_derive Add [lints] table, fix adding #![allow(clippy::type_complexity)] everywhere (#10011) 2023-11-18 20:58:48 +00:00
bevy_diagnostic Standardize toml format with taplo (#10594) 2023-11-21 01:04:14 +00:00
bevy_dylib Add [lints] table, fix adding #![allow(clippy::type_complexity)] everywhere (#10011) 2023-11-18 20:58:48 +00:00
bevy_dynamic_plugin Add [lints] table, fix adding #![allow(clippy::type_complexity)] everywhere (#10011) 2023-11-18 20:58:48 +00:00
bevy_ecs Split WorldQuery into WorldQueryData and WorldQueryFilter (#9918) 2023-11-28 03:56:07 +00:00
bevy_ecs_compile_fail_tests Split WorldQuery into WorldQueryData and WorldQueryFilter (#9918) 2023-11-28 03:56:07 +00:00
bevy_encase_derive Add [lints] table, fix adding #![allow(clippy::type_complexity)] everywhere (#10011) 2023-11-18 20:58:48 +00:00
bevy_gilrs Add [lints] table, fix adding #![allow(clippy::type_complexity)] everywhere (#10011) 2023-11-18 20:58:48 +00:00
bevy_gizmos move gizmo arcs to their own file (#10660) 2023-11-22 14:58:34 +00:00
bevy_gltf Fix GLTF scene dependencies and make full scene renders predictable (#10745) 2023-11-27 22:42:28 +00:00
bevy_hierarchy Split WorldQuery into WorldQueryData and WorldQueryFilter (#9918) 2023-11-28 03:56:07 +00:00
bevy_input Standardize toml format with taplo (#10594) 2023-11-21 01:04:14 +00:00
bevy_internal Standardize toml format with taplo (#10594) 2023-11-21 01:04:14 +00:00
bevy_log Standardize toml format with taplo (#10594) 2023-11-21 01:04:14 +00:00
bevy_macro_utils Allow #[derive(Bundle)] on tuple structs (take 3) (#10561) 2023-11-21 01:09:16 +00:00
bevy_macros_compile_fail_tests Standardize toml format with taplo (#10594) 2023-11-21 01:04:14 +00:00
bevy_math Use minor and major radii for Torus primitive shape (#10643) 2023-11-21 01:49:35 +00:00
bevy_mikktspace Enable clippy::undocumented_unsafe_blocks warning across the workspace (#10646) 2023-11-21 02:06:24 +00:00
bevy_pbr Ensure instance_index push constant is always used in prepass.wgsl (#10706) 2023-11-28 01:13:25 +00:00
bevy_ptr Enable clippy::undocumented_unsafe_blocks warning across the workspace (#10646) 2023-11-21 02:06:24 +00:00
bevy_reflect bevy_utils: Export generate_composite_uuid utility function (#10496) 2023-11-25 23:21:35 +00:00
bevy_reflect_compile_fail_tests Improve TypeUuid's derive macro error messages (#9315) 2023-10-02 12:42:01 +00:00
bevy_render Split WorldQuery into WorldQueryData and WorldQueryFilter (#9918) 2023-11-28 03:56:07 +00:00
bevy_scene Standardize toml format with taplo (#10594) 2023-11-21 01:04:14 +00:00
bevy_sprite Use as_image_copy where possible (#10733) 2023-11-26 19:24:32 +00:00
bevy_tasks bump bevy_tasks futures-lite to 2.0.1 (#10675) 2023-11-24 00:11:02 +00:00
bevy_text Standardize toml format with taplo (#10594) 2023-11-21 01:04:14 +00:00
bevy_time Wait until FixedUpdate can see events before dropping them (#10077) 2023-11-26 23:04:41 +00:00
bevy_transform Enable clippy::undocumented_unsafe_blocks warning across the workspace (#10646) 2023-11-21 02:06:24 +00:00
bevy_ui Split WorldQuery into WorldQueryData and WorldQueryFilter (#9918) 2023-11-28 03:56:07 +00:00
bevy_utils bevy_utils: Export generate_composite_uuid utility function (#10496) 2023-11-25 23:21:35 +00:00
bevy_window add new event WindowOccluded from winit (#10735) 2023-11-26 21:58:54 +00:00
bevy_winit add new event WindowOccluded from winit (#10735) 2023-11-26 21:58:54 +00:00