Commit graph

34 commits

Author SHA1 Message Date
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
Mike
687e379800
Updates for rust 1.73 (#10035)
# Objective

- Updates for rust 1.73

## Solution

- new doc check for `redundant_explicit_links`
- updated to text for compile fail tests

---

## Changelog

- updates for rust 1.73
2023-10-06 00:31:10 +00:00
Rob Parrett
a788e31ad5
Fix CI for Rust 1.72 (#9562)
# Objective

[Rust 1.72.0](https://blog.rust-lang.org/2023/08/24/Rust-1.72.0.html) is
now stable.

# Notes

- `let-else` formatting has arrived!
- I chose to allow `explicit_iter_loop` due to
https://github.com/rust-lang/rust-clippy/issues/11074.
  
We didn't hit any of the false positives that prevent compilation, but
fixing this did produce a lot of the "symbol soup" mentioned, e.g. `for
image in &mut *image_events {`.
  
  Happy to undo this if there's consensus the other way.

---------

Co-authored-by: François <mockersf@gmail.com>
2023-08-25 12:34:24 +00:00
ira
5f936b42b1
Resolve clippy issues for rust 1.70.0 (#8738)
- Supress false positive `redundant_clone` lints.
- Supress inactionable `result_large_err` lint.
Most of the size(50 out of 68 bytes) is coming from
`naga::WithSpan<naga::valid::ValidationError>`
2023-06-01 21:05:05 +00:00
Nicola Papale
e900bd9e12
Fix 1.69 CI clippy lints (#8450)
- Fix CI by implementing changes recommended by clippy
- It uncovered a bug in a `bevy_ecs` test. Nice!
2023-04-20 16:51:21 +00:00
Rob Parrett
b7ac5d5121
Update trybuild tests for Rust 1.68 (#8002) 2023-03-09 15:46:06 +00:00
Cameron
be22569db7 EntityMut: rename remove_intersection to remove and remove to take (#7810)
# Objective

- A more intuitive distinction between the two. `remove_intersection` is verbose and unclear.
- `EntityMut::remove` and `Commands::remove` should match.


## Solution

- What the title says.

---

## Migration Guide

Before
```rust
fn clear_children(parent: Entity, world: &mut World) {
    if let Some(children) = world.entity_mut(parent).remove::<Children>() {
        for &child in &children.0 {
            world.entity_mut(child).remove_intersection::<Parent>();
        }
    }
}
```

After
```rust
fn clear_children(parent: Entity, world: &mut World) {
    if let Some(children) = world.entity_mut(parent).take::<Children>() {
        for &child in &children.0 {
            world.entity_mut(child).remove::<Parent>();
        }
    }
}
```
2023-02-26 00:09:19 +00:00
Rob Parrett
ec0478d100 Fix clippy lints and failed test with Rust 1.66 (#6945)
# Objective

[Rust 1.66](https://blog.rust-lang.org/inside-rust/2022/12/12/1.66.0-prerelease.html) is coming in a few days, and bevy doesn't build with it.

Fix that.

## Solution

Replace output from a trybuild test, and fix a few new instances of `needless_borrow` and `unnecessary_cast` that are now caught.

## Note

Due to the trybuild test, this can't be merged until 1.66 is released.
2022-12-15 18:05:15 +00:00
JoJoJet
1af73624fa Simplify trait hierarchy for SystemParam (#6865)
# Objective

* Implementing a custom `SystemParam` by hand requires implementing three traits -- four if it is read-only.
* The trait `SystemParamFetch<'w, 's>` is a workaround from before we had generic associated types, and is no longer necessary.

## Solution

* Combine the trait `SystemParamFetch` with `SystemParamState`.
    * I decided to remove the `Fetch` name and keep the `State` name, since the former was consistently conflated with the latter.
* Replace the trait `ReadOnlySystemParamFetch` with `ReadOnlySystemParam`, which simplifies trait bounds in generic code.

---

## Changelog

- Removed the trait `SystemParamFetch`, moving its functionality to `SystemParamState`.
- Replaced the trait `ReadOnlySystemParamFetch` with `ReadOnlySystemParam`.

## Migration Guide

The trait `SystemParamFetch` has been removed, and its functionality has been transferred to `SystemParamState`.

```rust
// Before
impl SystemParamState for MyParamState {
    fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self { ... }
}
impl<'w, 's> SystemParamFetch<'w, 's> for MyParamState {
    type Item = MyParam<'w, 's>;
    fn get_param(...) -> Self::Item;
}

// After
impl SystemParamState for MyParamState {
    type Item<'w, 's> = MyParam<'w, 's>; // Generic associated types!
    fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self { ... }
    fn get_param<'w, 's>(...) -> Self::Item<'w, 's>;
}
```

The trait `ReadOnlySystemParamFetch` has been replaced with `ReadOnlySystemParam`.

```rust
// Before
unsafe impl ReadOnlySystemParamFetch for MyParamState {}

// After
unsafe impl<'w, 's> ReadOnlySystemParam for MyParam<'w, 's> {}
```
2022-12-11 18:34:14 +00:00
Rob Parrett
aa742395d3 Fix trybuild tests broken by rust 1.65 (#6457)
# Objective

- Fix tests that now fail in rust 1.65

## Solution

- Update `.stderr` files with new output
2022-11-03 15:09:27 +00:00
Theo Ottah
45e5eb1db3 Remove ExactSizeIterator from QueryCombinationIter (#5895)
# Objective

- `QueryCombinationIter` can have sizes greater than `usize::MAX`.
- Fixes #5846 

## Solution

- Only the implementation of `ExactSizeIterator` has been removed. Instead of using `query_combination.len()`, you can use `query_combination.size_hint().0` to get the same value as before.

---

## Migration Guide

- Switch to using other methods of getting the length.
2022-10-24 23:03:15 +00:00
Rob Parrett
543465b721 Fix tests breaking when new WorldQuery impls are added (#6317)
# Objective

I recently wanted to look at the possibility of adding `Mutated` and `Unchanged` query filters and was confronted with some seemingly unrelated broken tests.

These tests were written in such a way that changing the number of WorldQuery impls in the project would break them.

Fortunately, a [very recent release of trybuild](https://github.com/dtolnay/trybuild/releases/tag/1.0.70) has made this unnecessary. 

## Solution

Replace hardcoded numbers in test output with `$N` placeholders.
2022-10-21 11:15:06 +00:00
Carter Anderson
01aedc8431 Spawn now takes a Bundle (#6054)
# Objective

Now that we can consolidate Bundles and Components under a single insert (thanks to #2975 and #6039), almost 100% of world spawns now look like `world.spawn().insert((Some, Tuple, Here))`. Spawning an entity without any components is an extremely uncommon pattern, so it makes sense to give spawn the "first class" ergonomic api. This consolidated api should be made consistent across all spawn apis (such as World and Commands).

## Solution

All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input:

```rust
// before:
commands
  .spawn()
  .insert((A, B, C));
world
  .spawn()
  .insert((A, B, C);

// after
commands.spawn((A, B, C));
world.spawn((A, B, C));
```

All existing instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api. A new `spawn_empty` has been added, replacing the old `spawn` api.  

By allowing `world.spawn(some_bundle)` to replace `world.spawn().insert(some_bundle)`, this opened the door to removing the initial entity allocation in the "empty" archetype / table done in `spawn()` (and subsequent move to the actual archetype in `.insert(some_bundle)`).

This improves spawn performance by over 10%:
![image](https://user-images.githubusercontent.com/2694663/191627587-4ab2f949-4ccd-4231-80eb-80dd4d9ad6b9.png)

To take this measurement, I added a new `world_spawn` benchmark.

Unfortunately, optimizing `Commands::spawn` is slightly less trivial, as Commands expose the Entity id of spawned entities prior to actually spawning. Doing the optimization would (naively) require assurances that the `spawn(some_bundle)` command is applied before all other commands involving the entity (which would not necessarily be true, if memory serves). Optimizing `Commands::spawn` this way does feel possible, but it will require careful thought (and maybe some additional checks), which deserves its own PR. For now, it has the same performance characteristics of the current `Commands::spawn_bundle` on main.

**Note that 99% of this PR is simple renames and refactors. The only code that needs careful scrutiny is the new `World::spawn()` impl, which is relatively straightforward, but it has some new unsafe code (which re-uses battle tested BundlerSpawner code path).** 

---

## Changelog

- All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input
- All instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api
- World and Commands now have `spawn_empty()`, which is equivalent to the old `spawn()` behavior.  

## Migration Guide

```rust
// Old (0.8):
commands
  .spawn()
  .insert_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));

// Old (0.8):
commands.spawn_bundle((A, B, C));
// New (0.9)
commands.spawn((A, B, C));

// Old (0.8):
let entity = commands.spawn().id();
// New (0.9)
let entity = commands.spawn_empty().id();

// Old (0.8)
let entity = world.spawn().id();
// New (0.9)
let entity = world.spawn_empty();
```
2022-09-23 19:55:54 +00:00
targrub
a09dd034a2 Fix CI issues arising from use of Rust 1.64 (#6067)
## Objective

Fixes https://github.com/bevyengine/bevy/issues/6063

## Solution

- Use `then_some(x)` instead of `then( || x)`.
- Updated error logs from `bevy_ecs_compile_fail_tests`.

## Migration Guide

From Rust 1.63 to 1.64, a new Clippy error was added; now one should use `then_some(x)` instead of `then( || x)`.
2022-09-22 16:56:43 +00:00
ira
992681b59b Make Resource trait opt-in, requiring #[derive(Resource)] V2 (#5577)
*This PR description is an edited copy of #5007, written by @alice-i-cecile.*
# Objective
Follow-up to https://github.com/bevyengine/bevy/pull/2254. The `Resource` trait currently has a blanket implementation for all types that meet its bounds.

While ergonomic, this results in several drawbacks:

* it is possible to make confusing, silent mistakes such as inserting a function pointer (Foo) rather than a value (Foo::Bar) as a resource
* it is challenging to discover if a type is intended to be used as a resource
* we cannot later add customization options (see the [RFC](https://github.com/bevyengine/rfcs/blob/main/rfcs/27-derive-component.md) for the equivalent choice for Component).
* dependencies can use the same Rust type as a resource in invisibly conflicting ways
* raw Rust types used as resources cannot preserve privacy appropriately, as anyone able to access that type can read and write to internal values
* we cannot capture a definitive list of possible resources to display to users in an editor
## Notes to reviewers
 * Review this commit-by-commit; there's effectively no back-tracking and there's a lot of churn in some of these commits.
   *ira: My commits are not as well organized :')*
 * I've relaxed the bound on Local to Send + Sync + 'static: I don't think these concerns apply there, so this can keep things simple. Storing e.g. a u32 in a Local is fine, because there's a variable name attached explaining what it does.
 * I think this is a bad place for the Resource trait to live, but I've left it in place to make reviewing easier. IMO that's best tackled with https://github.com/bevyengine/bevy/issues/4981.

## Changelog
`Resource` is no longer automatically implemented for all matching types. Instead, use the new `#[derive(Resource)]` macro.

## Migration Guide
Add `#[derive(Resource)]` to all types you are using as a resource.

If you are using a third party type as a resource, wrap it in a tuple struct to bypass orphan rules. Consider deriving `Deref` and `DerefMut` to improve ergonomics.

`ClearColor` no longer implements `Component`. Using `ClearColor` as a component in 0.8 did nothing.
Use the `ClearColorConfig` in the `Camera3d` and `Camera2d` components instead.


Co-authored-by: Alice <alice.i.cecile@gmail.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: devil-ira <justthecooldude@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-08-08 21:36:35 +00:00
Boxy
eabcd27d93 make WorldQuery very flat (#5205)
# Objective

Simplify the worldquery trait hierarchy as much as possible by putting it all in one trait. If/when gats are stabilised this can be trivially migrated over to use them, although that's not why I made this PR, those reasons are:
- Moves all of the conceptually related unsafe code for a worldquery next to eachother
- Removes now unnecessary traits simplifying the "type system magic" in bevy_ecs

---

## Changelog

All methods/functions/types/consts on `FetchState` and `Fetch` traits have been moved to the `WorldQuery` trait and the other traits removed. `WorldQueryGats` now only contains an `Item` and `Fetch` assoc type.

## Migration Guide
Implementors should move items in impls to the `WorldQuery/Gats` traits and remove any `Fetch`/`FetchState` impls
Any use sites of items in the `Fetch`/`FetchState` traits should be updated to use the `WorldQuery` trait items instead


Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-08-04 21:51:02 +00:00
ira
83a9e16158 Replace many_for_each_mut with iter_many_mut. (#5402)
# Objective
Replace `many_for_each_mut` with `iter_many_mut` using the same tricks to avoid aliased mutability that `iter_combinations_mut` uses.

<sub>I tried rebasing the draft PR I made for this before and it died. F</sub>
## Why
`many_for_each_mut` is worse for a few reasons:
1. The closure prevents the use of `continue`, `break`, and `return` behaves like a limited `continue`.
2. rustfmt will crumple it and double the indentation when the line gets too long.
    ```rust
    query.many_for_each_mut(
        &entity_list,
        |(mut transform, velocity, mut component_c)| {
            // Double trouble.
        },
    );
    ```
3. It is more surprising to have `many_for_each_mut` as a mutable counterpart to `iter_many` than `iter_many_mut`.
4. It required a separate unsafe fn; more unsafe code to maintain.
5. The `iter_many_mut` API matches the existing `iter_combinations_mut` API.

Co-authored-by: devil-ira <justthecooldude@gmail.com>
2022-07-30 01:38:13 +00:00
harudagondi
959f3b1186 Allows conversion of mutable queries to immutable queries (#5376)
# Objective

- Allows conversion of mutable queries to immutable queries.
- Fixes #4606

## Solution

- Add `to_readonly` method on `Query`, which uses `QueryState::as_readonly`
- `AsRef` is not feasible because creation of new queries is needed.

---

## Changelog

### Added

- Allows conversion of mutable queries to immutable queries using `Query::to_readonly`.
2022-07-20 01:09:45 +00:00
Boxy
1ac8a476cf remove QF generics from all Query/State methods and types (#5170)
# Objective

remove `QF` generics from a bunch of types and methods on query related items. this has a few benefits:
- simplifies type signatures `fn iter(&self) -> QueryIter<'_, 's, Q::ReadOnly, F::ReadOnly>` is (imo) conceptually simpler than `fn iter(&self) -> QueryIter<'_, 's, Q, ROQueryFetch<'_, Q>, F>`
- `Fetch` is mostly an implementation detail but previously we had to expose it on every `iter` `get` etc method
- Allows us to potentially in the future simplify the `WorldQuery` trait hierarchy by removing the `Fetch` trait

## Solution

remove the `QF` generic and add a way to (unsafely) turn `&QueryState<Q1, F1>` into `&QueryState<Q2, F2>`

---

## Changelog/Migration Guide

The `QF` generic was removed from various `Query` iterator types and some methods, you should update your code to use the type of the corresponding worldquery of the fetch type that was being used, or call `as_readonly`/`as_nop` to convert a querystate to the appropriate type. For example:
`.get_single_unchecked_manual::<ROQueryFetch<Q>>(..)` -> `.as_readonly().get_single_unchecked_manual(..)`
`my_field: QueryIter<'w, 's, Q, ROQueryFetch<'w, Q>, F>` -> `my_field: QueryIter<'w, 's, Q::ReadOnly, F::ReadOnly>`
2022-07-19 00:45:00 +00:00
Nicola Papale
6c06fc5b7c Add ExactSizeIterator implementation for QueryCombinatonIter (#5148)
Following https://github.com/bevyengine/bevy/pull/5124 I decided to add the `ExactSizeIterator` impl for `QueryCombinationIter`.

Also:
- Clean up the tests for `size_hint` and `len` for both the normal `QueryIter` and `QueryCombinationIter`.
- Add tests to `QueryCombinationIter` when it shouldn't be `ExactSizeIterator`

---

## Changelog

- Added `ExactSizeIterator` implementation for `QueryCombinatonIter`
2022-07-13 16:08:48 +00:00
Carter Anderson
96f0ebb9af Fix rust 1.62 changes (#5154)
# Objective

CI is now failing with some changes that landed in 1.62.

## Solution

* Fix an unused lifetime by using it (we double-used the `w` lifetime).
* Update compile_fail error messages
* temporarily disable check-unused-dependencies
2022-06-30 19:24:28 +00:00
harudagondi
6e50b249a4 Update ExactSizeIterator impl to support archetypal filters (With, Without) (#5124)
# Objective

- Fixes #3142

## Solution

- Done according to #3142
- Created new marker trait `ArchetypeFilter`
- Implement said trait to:
  - `With<T>`
  - `Without<T>`
  - tuples containing only types that implement `ArchetypeFilter`, from 0 to 15 elements
  - `Or<T>` where T is a tuple as described previously
- Changed `ExactSizeIterator` impl to include a new generic that must implement `WorldQuery` and `ArchetypeFilter`
- Added new tests

---

## Changelog

### Added
- `Query`s with archetypal filters can now use `.iter().len()` to get the exact size of the iterator.
2022-06-29 02:15:28 +00:00
Boxy
407c080e59 Replace ReadOnlyFetch with ReadOnlyWorldQuery (#4626)
# Objective

- Fix a type inference regression introduced by #3001
- Make read only bounds on world queries more user friendly

ptrification required you to write `Q::Fetch: ReadOnlyFetch` as `for<'w> QueryFetch<'w, Q>: ReadOnlyFetch` which has the same type inference problem as `for<'w> QueryFetch<'w, Q>: FilterFetch<'w>` had, i.e. the following code would error:
```rust
#[derive(Component)]
struct Foo;

fn bar(a: Query<(&Foo, Without<Foo>)>) {
    foo(a);
}

fn foo<Q: WorldQuery>(a: Query<Q, ()>)
where
    for<'w> QueryFetch<'w, Q>: ReadOnlyFetch,
{
}
```
`for<..>` bounds are also rather user unfriendly..

## Solution

Remove the `ReadOnlyFetch` trait in favour of a `ReadOnlyWorldQuery` trait, and remove `WorldQueryGats::ReadOnlyFetch` in favor of `WorldQuery::ReadOnly` allowing the previous code snippet to be written as:
```rust
#[derive(Component)]
struct Foo;

fn bar(a: Query<(&Foo, Without<Foo>)>) {
    foo(a);
}

fn foo<Q: ReadOnlyWorldQuery>(a: Query<Q, ()>) {}
``` 
This avoids the `for<...>` bound which makes the code simpler and also fixes the type inference issue.

The reason for moving the two functions out of `FetchState` and into `WorldQuery` is to allow the world query `&mut T` to share a `State` with the `&T` world query so that it can have `type ReadOnly = &T`. Presumably it would be possible to instead have a `ReadOnlyRefMut<T>` world query and then do `type ReadOnly = ReadOnlyRefMut<T>` much like how (before this PR) we had a `ReadOnlyWriteFetch<T>`. A side benefit of the current solution in this PR is that it will likely make it easier in the future to support an API such as `Query<&mut T> -> Query<&T>`. The primary benefit IMO is just that `ReadOnlyRefMut<T>` and its associated fetch would have to reimplement all of the logic that the `&T` world query impl does but this solution avoids that :)

---

## Changelog/Migration Guide

The trait `ReadOnlyFetch` has been replaced with `ReadOnlyWorldQuery` along with the `WorldQueryGats::ReadOnlyFetch` assoc type which has been replaced with `<WorldQuery::ReadOnly as WorldQueryGats>::Fetch`
- Any where clauses such as `QueryFetch<Q>: ReadOnlyFetch` should be replaced with `Q: ReadOnlyWorldQuery`.
- Any custom world query impls should implement `ReadOnlyWorldQuery` insead of `ReadOnlyFetch`

Functions `update_component_access` and `update_archetype_component_access` have been moved from the `FetchState` trait to `WorldQuery`
- Any callers should now call `Q::update_component_access(state` instead of `state.update_component_access` (and `update_archetype_component_access` respectively)
- Any custom world query impls should move the functions from the `FetchState` impl to `WorldQuery` impl

`WorldQuery` has been made an `unsafe trait`, `FetchState` has been made a safe `trait`. (I think this is how it should have always been, but regardless this is _definitely_ necessary now that the two functions have been moved to `WorldQuery`)
- If you have a custom `FetchState` impl make it a normal `impl` instead of `unsafe impl`
- If you have a custom `WorldQuery` impl make it an `unsafe impl`, if your code was sound before it is going to still be sound
2022-06-13 23:35:54 +00:00
ira
92ddfe8ad4 Add methods for querying lists of entities. (#4879)
# Objective
Improve querying ergonomics around collections and iterators of entities.

Example how queries over Children might be done currently. 
```rust
fn system(foo_query: Query<(&Foo, &Children)>, bar_query: Query<(&Bar, &Children)>) {
    for (foo, children) in &foo_query {
        for child in children.iter() {
            if let Ok((bar, children)) = bar_query.get(*child) {
                for child in children.iter() {
                    if let Ok((foo, children)) = foo_query.get(*child) {
                        // D:
                    }
                }
            }
        }
    }
}
```
Answers #4868
Partially addresses #4864
Fixes #1470
## Solution
Based on the great work by @deontologician in #2563 

Added `iter_many` and `many_for_each_mut` to `Query`.
These take a list of entities (Anything that implements `IntoIterator<Item: Borrow<Entity>>`).

`iter_many` returns a `QueryManyIter` iterator over immutable results of a query (mutable data will be cast to an immutable form).

`many_for_each_mut` calls a closure for every result of the query, ensuring not aliased mutability. 
This iterator goes over the list of entities in order and returns the result from the query for it. Skipping over any entities that don't match the query.

Also added `unsafe fn iter_many_unsafe`.

### Examples
```rust
#[derive(Component)]
struct Counter {
    value: i32
}

#[derive(Component)]
struct Friends {
    list: Vec<Entity>,
}

fn system(
    friends_query: Query<&Friends>,
    mut counter_query: Query<&mut Counter>,
) {
    for friends in &friends_query {
        for counter in counter_query.iter_many(&friends.list) {
            println!("Friend's counter: {:?}", counter.value);
        }
        
        counter_query.many_for_each_mut(&friends.list, |mut counter| {
            counter.value += 1;
            println!("Friend's counter: {:?}", counter.value);
        });
    }
}

```

Here's how example in the Objective section can be written with this PR.
```rust
fn system(foo_query: Query<(&Foo, &Children)>, bar_query: Query<(&Bar, &Children)>) {
    for (foo, children) in &foo_query {
        for (bar, children) in bar_query.iter_many(children) {
            for (foo, children) in foo_query.iter_many(children) {
                // :D
            }
        }
    }
}
```
## Additional changes
Implemented `IntoIterator` for `&Children` because why not.
## Todo
- Bikeshed!

Co-authored-by: deontologician <deontologician@gmail.com>

Co-authored-by: devil-ira <justthecooldude@gmail.com>
2022-06-06 16:09:16 +00:00
Daniel McNab
38a940dbbe Make derived SystemParam readonly if possible (#4650)
Required for https://github.com/bevyengine/bevy/pull/4402.

# Objective

- derived `SystemParam` implementations were never `ReadOnlySystemParamFetch`
- We want them to be, e.g. for `EventReader`

## Solution

- If possible, 'forward' the impl of `ReadOnlySystemParamFetch`.
2022-05-09 16:09:33 +00:00
Boxy
b9102b8836 Introduce tests for derive(WorldQuery) (#4625)
The only tests we had for `derive(WorldQuery)` checked that the derive doesnt panic/emit a `compiler_error!`. This PR adds tests that actually assert the returned values of a query using the derived `WorldQuery` impl. Also adds a compile fail test to check that we correctly error on read only world queries containing mutable world queries.
2022-04-28 21:06:20 +00:00
Boxy
dba7790012 REMOVE unsound lifetime annotations on EntityMut (#4096)
Fixes #3408
#3001 also solves this but I dont see it getting merged any time soon so...
# Objective
make bevy ecs a lil bit less unsound

## Solution
make `EntityMut::get_component_mut` return borrows from self instead of `'w`
2022-04-04 21:33:33 +00:00
Alice Cecile
b33dae31ec Rename get_multiple APIs to get_many (#4384)
# Objective

-  std's new APIs do the same thing as `Query::get_multiple_mut`, but are called `get_many`: https://github.com/rust-lang/rust/pull/83608

## Solution

- Find and replace `get_multiple` with `get_many`
2022-03-31 20:59:26 +00:00
Alice Cecile
509548190b Add get_multiple and get_multiple_mut APIs for Query and QueryState (#4298)
# Objective

- The inability to have multiple active mutable borrows into a query is a common source of borrow-checker pain for users.
- This is a pointless restriction if and only if we can guarantee that the entities they are accessing are unique.
- This could already by bypassed with get_unchecked, but that is an extremely unsafe API.
- Closes https://github.com/bevyengine/bevy/issues/2042.

## Solution

- Add `get_multiple`, `get_multiple_mut` and their unchecked equivalents (`multiple` and `multiple_mut`) to `Query` and `QueryState`.
- Improve the `QueryEntityError` type to provide more useful error information.

## Changelog

- Added `get_multiple`, `get_multiple_mut` and their unchecked equivalents (`multiple` and `multiple_mut`) to Query and QueryState.

## Migration Guide

- The `QueryEntityError` enum now has a `AliasedMutability variant, and returns the offending entity.

## Context

This is a fresh attempt at #3333; rebasing was behaving very badly and it was important to rebase on top of the recent query soundness fixes. Many thanks to all the reviewers in that thread, especially @BoxyUwU for the help with lifetimes.

## To-do

- [x] Add compile fail tests
- [x] Successfully deduplicate code
- [x] Decide what to do about failing doc tests
- [x] Get some reviews for lifetime soundness
2022-03-30 19:16:48 +00:00
bilsen
63fee2572b ParamSet for conflicting SystemParam:s (#2765)
# Objective
Add a system parameter `ParamSet` to be used as container for conflicting parameters.

## Solution
Added two methods to the SystemParamState trait, which gives the access used by the parameter. Did the implementation. Added some convenience methods to FilteredAccessSet. Changed `get_conflicts` to return every conflicting component instead of breaking on the first conflicting `FilteredAccess`.


Co-authored-by: bilsen <40690317+bilsen@users.noreply.github.com>
2022-03-29 23:39:38 +00:00
Boxy
024d98457c yeet unsound lifetime annotations on Query methods (#4243)
# Objective
Continuation of #2964 (I really should have checked other methods when I made that PR)

yeet unsound lifetime annotations on `Query` methods.
Example unsoundness:
```rust
use bevy::prelude::*;

fn main() {
    App::new().add_startup_system(bar).add_system(foo).run();
}

pub fn bar(mut cmds: Commands) {
    let e = cmds.spawn().insert(Foo { a: 10 }).id();
    cmds.insert_resource(e);
}

#[derive(Component, Debug, PartialEq, Eq)]
pub struct Foo {
    a: u32,
}
pub fn foo(mut query: Query<&mut Foo>, e: Res<Entity>) {
    dbg!("hi");
    {
        let data: &Foo = query.get(*e).unwrap();
        let data2: Mut<Foo> = query.get_mut(*e).unwrap();
        assert_eq!(data, &*data2); // oops UB
    }

    {
        let data: &Foo = query.single();
        let data2: Mut<Foo> = query.single_mut();
        assert_eq!(data, &*data2); // oops UB
    }

    {
        let data: &Foo = query.get_single().unwrap();
        let data2: Mut<Foo> = query.get_single_mut().unwrap();
        assert_eq!(data, &*data2); // oops UB
    }

    {
        let data: &Foo = query.iter().next().unwrap();
        let data2: Mut<Foo> = query.iter_mut().next().unwrap();
        assert_eq!(data, &*data2); // oops UB
    }

    {
        let mut opt_data: Option<&Foo> = None;
        let mut opt_data_2: Option<Mut<Foo>> = None;
        query.for_each(|data| opt_data = Some(data));
        query.for_each_mut(|data| opt_data_2 = Some(data));
        assert_eq!(opt_data.unwrap(), &*opt_data_2.unwrap()); // oops UB
    }
    dbg!("bye");
}

```

## Solution
yeet unsound lifetime annotations on `Query` methods

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-03-22 02:49:41 +00:00
François
c6fec1f0c2 Fix clippy lints for 1.57 (#3238)
# Objective

- New clippy lints with rust 1.57 are failing

## Solution

- Fixed clippy lints following suggestions
- I ignored clippy in old renderer because there was many and it will be removed soon
2021-12-02 23:40:37 +00:00
Joshua Chapman
274ace790b Implement iter() for mutable Queries (#2305)
A sample implementation of how to have `iter()` work on mutable queries without breaking aliasing rules.

# Objective

- Fixes #753

## Solution

- Added a ReadOnlyFetch to WorldQuery that is the `&T` version of `&mut T` that is used to specify the return type for read only operations like `iter()`.
- ~~As the comment suggests specifying the bound doesn't work due to restrictions on defining recursive implementations (like `Or`). However bounds on the functions are fine~~ Never mind I misread how `Or` was constructed, bounds now exist.
- Note that the only mutable one has a new `Fetch` for readonly as the `State` has to be the same for any of this to work


Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-12-01 23:28:10 +00:00
Niklas Eicker
d0f423d653 Assert compiler errors for compile_fail tests (#3067)
# Objective

bevy_ecs has several compile_fail tests that assert lifetime safety. In the past, these tests have been green for the wrong reasons (see e.g. #2984). This PR makes sure, that they will fail if the compiler error changes.

## Solution

Use [trybuild](https://crates.io/crates/trybuild) to assert the compiler errors.

The UI tests are in a separate crate that is not part of the Bevy workspace. This is to ensure that they do not break Bevy's crater builds. The tests get executed by the CI workflow on the stable toolchain.
2021-11-13 22:43:19 +00:00