Commit Graph

413 Commits

Author SHA1 Message Date
MichiRecRoom
447108b2a4
Downgrade clippy::allow_attributes and clippy::allow_attributes_without_reason to warn (#17320)
# Objective
I realized that setting these to `deny` may have been a little
aggressive - especially since we upgrade warnings to denies in CI.

## Solution
Downgrades these lints to `warn`, so that compiles can work locally. CI
will still treat these as denies.
2025-01-12 05:28:26 +00:00
Rob Parrett
b77e3ef33a
Fix a few typos (#17292)
# Objective

Stumbled upon a `from <-> form` transposition while reviewing a PR,
thought it was interesting, and went down a bit of a rabbit hole.

## Solution

Fix em
2025-01-10 22:48:30 +00:00
Zachary Harrold
d60764908c
Update downcast-rs to version 2 (#17223)
# Objective & Solution

- Update `downcast-rs` to the latest version, 2.
- Disable (new) `sync` feature to improve compatibility with atomically
challenged platforms.
- Remove stub `downcast-rs` alternative code from `bevy_app`

## Testing

- CI

## Notes

The only change from version 1 to version 2 is the addition of a new
`sync` feature, which allows disabling the `DowncastSync` parts of
`downcast-rs`, which require access to `alloc::sync::Arc`, which is not
available on atomically challenged platforms. Since Bevy makes no use of
the functionality provided by the `sync` feature, I've disabled it in
all crates. Further details can be found
[here](https://github.com/marcianx/downcast-rs/pull/22).
2025-01-07 21:33:40 +00:00
Nándor Szalma
7f74e3c2f9
Fix depth_bias and build errors on less capable platforms (#17079)
# Objective

- I'm compiling (parts of) bevy for an embedded platform with no 64bit
atomic and ctrlc handler support. Some compilation errors came up. This
PR contains the fixes for those.
- Fix depth_bias casting in PBR material (Fixes #14169)
  - Negative depth_bias values were casted to 0 before this PR
  - f32::INFINITY depth_bias value was casted to -1 before this PR

## Solutions

- Restrict 64bit atomic reflection to supported platforms
- Restrict ctrlc handler to supported platforms (linux, windows or macos
instead of "not wasm")
- The depth bias value (f32) is first casted to i32 then u64 in order to
preserve negative values

## Testing
- This version compiles on a platform with no 64bit atomic support, and
no ctrlc support
- CtrlC handler still works on Linux and Windows (I can't test on Macos)
- depth_bias:
```rust
println!("{}",f32::INFINITY as u64 as i32); // Prints: -1 (old implementation)
println!("{}",f32::INFINITY as i32 as u64 as i32); // Prints: 2147483647 (expected, new implementation)
```
Also ran a modified version of 3d_scene example with the following
results:

RED cube depth_bias: -1000.0
BLUE cube depth_bias: 0.0

![image](https://github.com/user-attachments/assets/d5a96759-dd3c-4a0a-97ff-821163873a0d)

RED cube depth_bias: -INF
BLUE cube depth_bias: 0.0

![image](https://github.com/user-attachments/assets/e4de22b4-0c31-4dea-8be1-12b700e440b9)

RED cube depth_bias: INF (case reported in #14169)
BLUE cube depth_bias: 0.0
(Im not completely sure whats going on with the shadows here, it seems
like depth_bias has some affect to those aswell, if this is
unintentional this issue was not introduced by this PR)

![image](https://github.com/user-attachments/assets/52d9348f-df27-468f-a001-2d3d3ff6b553)
2025-01-06 18:39:08 +00:00
MichiRecRoom
21c1b6a1e8
Update all previously-merged #![deny(clippy::allow_attributes, clippy::allow_attributes_without_reason)] attributes to include a reason field pointing to the tracking issue (#17136)
# Objective
Ensure the deny lint attributes added as a result of #17111 point to the
tracking issue.

## Solution
Change all existing instances of:
```rust
#![deny(clippy::allow_attributes, clippy::allow_attributes_without_reason)]
```
to
```rust
#![deny(
    clippy::allow_attributes,
    clippy::allow_attributes_without_reason,
    reason = "See #17111; To be removed once all crates are in-line with these attributes"
)]
```

## Testing
N/A
2025-01-06 05:40:08 +00:00
github-actions[bot]
573b980685
Bump Version after Release (#17176)
Bump version after release
This PR has been auto-generated

---------

Co-authored-by: Bevy Auto Releaser <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: François Mockers <mockersf@gmail.com>
2025-01-06 00:04:44 +00:00
Zachary Harrold
3c829d7f68
Remove everything except Instant from bevy_utils::time (#17158)
# Objective

- Contributes to #11478
- Contributes to #16877

## Solution

- Removed everything except `Instant` from `bevy_utils::time`

## Testing

- CI

---

## Migration Guide

If you relied on any of the following from `bevy_utils::time`:

- `Duration`
- `TryFromFloatSecsError`

Import these directly from `core::time` regardless of platform target
(WASM, mobile, etc.)

If you relied on any of the following from `bevy_utils::time`:

- `SystemTime`
- `SystemTimeError`

Instead import these directly from either `std::time` or `web_time` as
appropriate for your target platform.

## Notes

`Duration` and `TryFromFloatSecsError` are both re-exports from
`core::time` regardless of whether they are used from `web_time` or
`std::time`, so there is no value gained from re-exporting them from
`bevy_utils::time` as well. As for `SystemTime` and `SystemTimeError`,
no Bevy internal crates or examples rely on these types. Since Bevy
doesn't have a `Time<Wall>` resource for interacting with wall-time (and
likely shouldn't need one), I think removing these from `bevy_utils`
entirely and waiting for a use-case to justify inclusion is a reasonable
path forward.
2025-01-05 20:36:08 +00:00
Zachary Harrold
0403948aa2
Remove Implicit std Prelude from no_std Crates (#17086)
# Background

In `no_std` compatible crates, there is often an `std` feature which
will allow access to the standard library. Currently, with the `std`
feature _enabled_, the
[`std::prelude`](https://doc.rust-lang.org/std/prelude/index.html) is
implicitly imported in all modules. With the feature _disabled_, instead
the [`core::prelude`](https://doc.rust-lang.org/core/prelude/index.html)
is implicitly imported. This creates a subtle and pervasive issue where
`alloc` items _may_ be implicitly included (if `std` is enabled), or
must be explicitly included (if `std` is not enabled).

# Objective

- Make the implicit imports for `no_std` crates consistent regardless of
what features are/not enabled.

## Solution

- Replace the `cfg_attr` "double negative" `no_std` attribute with
conditional compilation to _include_ `std` as an external crate.
```rust
// Before
#![cfg_attr(not(feature = "std"), no_std)]

// After
#![no_std]

#[cfg(feature = "std")]
extern crate std;
```
- Fix imports that are currently broken but are only now visible with
the above fix.

## Testing

- CI

## Notes

I had previously used the "double negative" version of `no_std` based on
general consensus that it was "cleaner" within the Rust embedded
community. However, this implicit prelude issue likely was considered
when forming this consensus. I believe the reason why is the items most
affected by this issue are provided by the `alloc` crate, which is
rarely used within embedded but extensively used within Bevy.
2025-01-03 01:58:43 +00:00
MichiRecRoom
5d00ef4237
bevy_app: Apply #[deny(clippy::allow_attributes, clippy::allow_attributes_without_reason)] (#17095)
# Objective
We want to deny the following lints:
* `clippy::allow_attributes` - Because there's no reason to
`#[allow(...)]` an attribute if it wouldn't lint against anything; you
should always use `#[expect(...)]`
* `clippy::allow_attributes_without_reason` - Because documenting the
reason for allowing/expecting a lint is always good

## Solution
Set the `clippy::allow_attributes` and
`clippy::allow_attributes_without_reason` lints to `deny`, and bring
`bevy_reflect` in line with the new restrictions.

No code changes have been made - except if a lint that was previously
`allow(...)`'d could be removed via small code changes. For example,
`unused_variables` can be handled by adding a `_` to the beginning of a
field's name.

## Testing
I ran `cargo clippy`, and received no errors.
2025-01-02 18:44:34 +00:00
ickshonpe
7a5a734452
Replace map + unwrap_or(false) with is_some_and (#17067)
# Objective

The `my_option.map(|inner| inner.is_whatever).unwrap_or(false)` pattern
is fragile and ugly.

Replace it with `is_some_and` everywhere.
2024-12-31 20:28:02 +00:00
Benjamin Brienen
4460a4d9ed
Use -D warnings in all relevant CI (#17011)
# Objective

Fixes #17009

See:
https://doc.rust-lang.org/stable/clippy/continuous_integration/index.html

## Solution

Add the env

## Testing

CI should start to fail, then I'll fix it.

## Showcase


![image](https://github.com/user-attachments/assets/acd2888f-9fc0-445a-a96a-842ba9f1c6aa)
2024-12-31 00:15:28 +00:00
Zachary Harrold
5f42c9ab6d
Fix no_std CI Warnings and WASM Compatibility (#17049)
# Objective

- Resolve several warnings encountered when compiling for `no_std`
around `dead_code`
- Fix compatibility with `wasm32-unknown-unknown` when using `no_std`
(identified by Sachymetsu on
[Discord](https://discord.com/channels/691052431525675048/692572690833473578/1323365426901549097))

## Solution

- Removed some unused imports
- Added `allow(dead_code)` for certain private items when compiling on
`no_std`
- Fixed `bevy_app` and `bevy_tasks` compatibility with WASM when
compiling without `std` by appropriately importing `Box` and feature
gating panic unwinding

## Testing

- CI
2024-12-30 23:01:27 +00:00
Brezak
ae16bdf172
Add fallible add methods to PluginGroupBuilder (#17005)
# Objective

Make working with `PluginGroupBuilder` less panicky.
Fixes #17001

## Solution

Expand the `PluginGroupBuilder` api with fallible add methods + a
contains method.
Also reorder the `PluginGroupBuilder` tests because before should come
before after.

## Testing

Ran the `PluginGroupBuilder` tests which call into all the newly added
methods.
2024-12-30 20:14:02 +00:00
Jerome Humbert
f9c8f511fd
Add SubApp::take_extract() (#16862)
# Objective

Fixes #16850

## Solution

Add a new function `SubApp::take_extract()`, similar to
`Option::take()`, which allows stealing the currently installed extract
function of a sub-app, with the intent to replace it with a custom one
calling the original one via `set_extract()`.

This pattern enables registering a custom "world sync" function similar
to the existing one `entity_sync_system()`, to run custom world sync
logic with mutable access to both the main and render worlds.

## Testing

`cargo r -p ci` currently doesn't build locally, event after upgrading
rustc to latest and doing a `cargo update`.
2024-12-24 18:26:32 +00:00
MichiRecRoom
4a681c3f05
Expose access to SubApps within App (#16952)
# Objective
`SubApps` is visible within the documentation for `bevy_app`. However,
no way of accessing the `SubApps` field in `App` is currently available.

## Solution
Expose two new functions, `App::sub_apps()` and `App::sub_apps_mut()`,
which give immutable and mutable access to `SubApps` respectively.

The other solution is to hide `SubApps`, which I submitted as a PR at
<https://github.com/bevyengine/bevy/pull/16953>.

## Testing
Because of the simplicity of the changes, I only tested by compiling
`bevy_app` - which compiled successfully.

Note: `SubApps`, and its corresponding field on `App`, are not used
outside of `bevy_app` - which means that compiling the other crates is
not necessary.
2024-12-24 06:15:16 +00:00
Zachary Harrold
21786632c3
Remove bevy_core (#16897)
# Objective

- Fixes #16892

## Solution

- Removed `TypeRegistryPlugin` (`Name` is now automatically registered
with a default `App`)
- Moved `TaskPoolPlugin` to `bevy_app`
- Moved `FrameCountPlugin` to `bevy_diagnostic`
- Deleted now-empty `bevy_core`

## Testing

- CI

## Migration Guide

- `TypeRegistryPlugin` no longer exists. If you can't use a default
`App` but still need `Name` registered, do so manually with
`app.register_type::<Name>()`.
- References to `TaskPoolPlugin` and associated types will need to
import it from `bevy_app` instead of `bevy_core`
- References to `FrameCountPlugin` and associated types will need to
import it from `bevy_diagnostic` instead of `bevy_core`

## Notes

This strategy was agreed upon by Cart and several other members in
[Discord](https://discord.com/channels/691052431525675048/692572690833473578/1319137218312278077).
2024-12-19 18:36:51 +00:00
Zachary Harrold
f45e78e658
Add no_std support to bevy_app (#16874)
# Objective

- Contributes to #15460

## Solution

- Added the following features:
  - `std` (default)
  - `bevy_tasks` (default)
  - `downcast ` (default)
  - `portable-atomic`
  - `critical-section`
- `downcast` and `bevy_tasks` are now optional dependencies for
`bevy_app`.

## Testing

- CI
- Personal UEFI and Raspberry Pi Pico demo applications compile and run
against this branch

## Draft Release Notes

Bevy's application framework now supports `no_std` platforms.

Following up on `bevy_ecs` gaining `no_std` support, `bevy_app` extends
the functionality available on these targets to include the powerful
`App` and `Plugin` abstractions. With this, library authors now have the
option of making their plugins `no_std` compatible, or even offering
plugins specifically to improve Bevy on certain embedded platforms!

To start making a `no_std` compatible plugin, simply disable default
features when including `bevy_app`:

```toml
[dependencies]
bevy_app = { version = "0.16", default-features = false }
```

We encourage library authors to do this anyway, as it can also help with
compile times and binary size on all platforms.

Keep an eye out for future `no_std` updates as we continue to improve
the parity between `std` and `no_std`. We look forward to seeing what
kinds of applications are now possible with Bevy!

## Notes

- `downcast-rs` is optional as it isn't compatible with
`portable-atomic`. I will investigate making a PR upstream to add
support for this functionality, as it should be very straightforward.
- In line with the `bevy_ecs` no-std-ification, I've added documentation
to all features, and grouped them as well.
- ~~Creating this PR in draft while CI runs and so I can polish before
review.~~

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-12-18 22:04:45 +00:00
Chris Russell
3ef99cf82c
Replace impl_param_set proc macro with a macro_rules macro (#16847)
# Objective

Simplify the code by using `macro_rules` instead of a proc macro where
possible.

## Solution

Replace `impl_param_set` proc macro with a `macro_rules` macro.
2024-12-18 18:30:46 +00:00
Rich Churcher
f2719f5470
Rust 1.83, allow -> expect (missing_docs) (#16561)
# Objective

We were waiting for 1.83 to address most of these, due to a bug with
`missing_docs` and `expect`. Relates to, but does not entirely complete,
#15059.

## Solution

- Upgrade to 1.83
- Switch `allow(missing_docs)` to `expect(missing_docs)`
- Remove a few now-unused `allow`s along the way, or convert to `expect`
2024-12-16 23:27:57 +00:00
Clar Fon
711246aa34
Update hashbrown to 0.15 (#15801)
Updating dependencies; adopted version of #15696. (Supercedes #15696.)

Long answer: hashbrown is no longer using ahash by default, meaning that
we can't use the default-hasher methods with ahasher. So, we have to use
the longer-winded versions instead. This takes the opportunity to also
switch our default hasher as well, but without actually enabling the
default-hasher feature for hashbrown, meaning that we'll be able to
change our hasher more easily at the cost of all of these method calls
being obnoxious forever.

One large change from 0.15 is that `insert_unique_unchecked` is now
`unsafe`, and for cases where unsafe code was denied at the crate level,
I replaced it with `insert`.

## Migration Guide

`bevy_utils` has updated its version of `hashbrown` to 0.15 and now
defaults to `foldhash` instead of `ahash`. This means that if you've
hard-coded your hasher to `bevy_utils::AHasher` or separately used the
`ahash` crate in your code, you may need to switch to `foldhash` to
ensure that everything works like it does in Bevy.
2024-12-10 19:45:50 +00:00
Zachary Harrold
a6adced9ed
Deny derive_more error feature and replace it with thiserror (#16684)
# Objective

- Remove `derive_more`'s error derivation and replace it with
`thiserror`

## Solution

- Added `derive_more`'s `error` feature to `deny.toml` to prevent it
sneaking back in.
- Reverted to `thiserror` error derivation

## Notes

Merge conflicts were too numerous to revert the individual changes, so
this reversion was done manually. Please scrutinise carefully during
review.
2024-12-06 17:03:55 +00:00
Benjamin Brienen
afd0f1322d
Move all_tuples to a new crate (#16161)
# Objective

Fixes #15941

## Solution

Created https://crates.io/crates/variadics_please and moved the code
there; updating references

`bevy_utils/macros` is deleted.

## Testing

cargo check

## Migration Guide

Use `variadics_please::{all_tuples, all_tuples_with_size}` instead of
`bevy::utils::{all_tuples, all_tuples_with_size}`.
2024-12-03 17:41:09 +00:00
MichiRecRoom
2a66bf0909
Clarify that bevy_app::App.world() (and mut variant) returns the main SubApp's World (#16527)
# Objective
The documentation for `bevy_app::App.world()` (and its mut variant)
could confuse some into thinking that this is the only World that the
App will contain.

## Solution
Clarify the documentation for `bevy_app::App.world()` (and its mut
variant), to say that it returns the main subapp's world. This helps
imply that Apps can contain more than one world (albeit, only one per
SubApp).

## Testing
This is a documentation change, with no changes to doctests. Thus,
testing is not necessary beyond ensuring the link syntax is correct.
2024-11-27 16:09:09 +00:00
Carter Anderson
513be52505
AnimationEvent -> Event and other improvements (#16440)
# Objective

Needing to derive `AnimationEvent` for `Event` is unnecessary, and the
trigger logic coupled to it feels like we're coupling "event producer"
logic with the event itself, which feels wrong. It also comes with a
bunch of complexity, which is again unnecessary. We can have the
flexibility of "custom animation event trigger logic" without this
coupling and complexity.

The current `animation_events` example is also needlessly complicated,
due to it needing to work around system ordering issues. The docs
describing it are also slightly wrong. We can make this all a non-issue
by solving the underlying ordering problem.

Related to this, we use the `bevy_animation::Animation` system set to
solve PostUpdate animation order-of-operations issues. If we move this
to bevy_app as part of our "core schedule", we can cut out needless
`bevy_animation` crate dependencies in these instances.

## Solution

- Remove `AnimationEvent`, the derive, and all other infrastructure
associated with it (such as the `bevy_animation/derive` crate)
- Replace all instances of `AnimationEvent` traits with `Event + Clone`
- Store and use functions for custom animation trigger logic (ex:
`clip.add_event_fn()`). For "normal" cases users dont need to think
about this and should use the simpler `clip.add_event()`
- Run the `Animation` system set _before_ updating text
- Move `bevy_animation::Animation` to `bevy_app::Animation`. Remove
unnecessary `bevy_animation` dependency from `bevy_ui`
- Adjust `animation_events` example to use the simpler `clip.add_event`
API, as the workarounds are no longer necessary

This is polishing work that will land in 0.15, and I think it is simple
enough and valuable enough to land in 0.15 with it, in the interest of
making the feature as compelling as possible.
2024-11-22 00:16:04 +00:00
Benjamin Brienen
3e405ed537
Improve SubApp documentation example (#16160)
# Objective

Fix #15841

## Solution

Added an update schedule as recommended in the issue.

## Testing

Doc test is run and passes.

Ran the example in a test app before and after adding the line.

## Showcase

Before:

```
PS C:\Users\BenjaminBrienen\source\bevy_experiment_test> cargo run
    Blocking waiting for file lock on build directory
   Compiling bevy_experiment_test v0.1.0 (C:\Users\BenjaminBrienen\source\bevy_experiment_test)
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 1m 41s
     Running `target\debug\bevy_experiment_test.exe`
```

(nothing happens)

After:

```
PS C:\Users\BenjaminBrienen\source\bevy_experiment_test> cargo run
    Blocking waiting for file lock on build directory
   Compiling bevy_experiment_test v0.1.0 (C:\Users\BenjaminBrienen\source\bevy_experiment_test)
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 14.64s
     Running `target\debug\bevy_experiment_test.exe`
system of subapp is executing and the Counter: 10
```
2024-10-30 22:12:25 +00:00
BD103
7c593179e3
Fix bevy_picking plugin suffixes (#16082)
# Objective

- `MeshPickingBackend` and `SpritePickingBackend` do not have the
`Plugin` suffix
- `DefaultPickingPlugins` is masquerading as a `Plugin` when in reality
it should be a `PluginGroup`
- Fixes #16081.

## Solution

- Rename some structures:

|Original Name|New Name|
|-|-|
|`MeshPickingBackend`|`MeshPickingPlugin`|
|`MeshPickingBackendSettings`|`MeshPickingSettings`|
|`SpritePickingBackend`|`SpritePickingPlugin`|
|`UiPickingBackendPlugin`|`UiPickingPlugin`|

- Make `DefaultPickingPlugins` a `PluginGroup`.
- Because `DefaultPickingPlugins` is within the `DefaultPlugins` plugin
group, I also added support for nested plugin groups to the
`plugin_group!` macro.

## Testing

- I used ripgrep to ensure all references were properly renamed.
- For the `plugin_group!` macro, I used `cargo expand` to manually
inspect the expansion of `DefaultPlugins`.

---

## Migration Guide

> [!NOTE]
>
> All 3 of the changed structures were added after 0.14, so this does
not need to be included in the 0.14 to 0.15 migration guide.

- `MeshPickingBackend` is now named `MeshPickingPlugin`.
- `MeshPickingBackendSettings` is now named `MeshPickingSettings`.
- `SpritePickingBackend` is now named `SpritePickingPlugin`.
- `UiPickingBackendPlugin` is now named `UiPickingPlugin`.
- `DefaultPickingPlugins` is now a a `PluginGroup` instead of a
`Plugin`.
2024-10-25 20:11:51 +00:00
Pablo Reinhardt
d96a9d15f6
Migrate from Query::single and friends to Single (#15872)
# Objective

- closes #15866

## Solution

- Simply migrate where possible.

## Testing

- Expect that CI will do most of the work. Examples is another way of
testing this, as most of the work is in that area.
---

## Notes
For now, this PR doesn't migrate `QueryState::single` and friends as for
now, this look like another issue. So for example, QueryBuilders that
used single or `World::query` that used single wasn't migrated. If there
is a easy way to migrate those, please let me know.

Most of the uses of `Query::single` were removed, the only other uses
that I found was related to tests of said methods, so will probably be
removed when we remove `Query::single`.
2024-10-13 20:32:06 +00:00
Christian Hughes
219b5930f1
Rename App/World::observe to add_observer, EntityWorldMut::observe_entity to observe. (#15754)
# Objective

- Closes #15752

Calling the functions `App::observe` and `World::observe` doesn't make
sense because you're not "observing" the `App` or `World`, you're adding
an observer that listens for an event that occurs *within* the `World`.
We should rename them to better fit this.

## Solution

Renames:
- `App::observe` -> `App::add_observer`
- `World::observe` -> `World::add_observer`
- `Commands::observe` -> `Commands::add_observer`
- `EntityWorldMut::observe_entity` -> `EntityWorldMut::observe`

(Note this isn't a breaking change as the original rename was introduced
earlier this cycle.)

## Testing

Reusing current tests.
2024-10-09 15:39:29 +00:00
Zachary Harrold
1be0ed33fc
Remove thiserror from bevy_app (#15779)
# Objective

- Contributes to #15460

## Solution

- Removed `thiserror` from `bevy_app`
2024-10-09 14:17:52 +00:00
Benjamin Brienen
c841dd92a1
Documentation for variadics (#15387)
# Objective

Relevant: #15208

## Solution

I went ahead and added the variadics documentation in all applicable
locations.

## Testing

- I built the documentation and inspected it to see whether the feature
is there.
2024-10-02 12:48:36 +00:00
Joona Aalto
f3e8ae03cd
Runtime required components (#15458)
# Objective

Fixes #15367.

Currently, required components can only be defined through the `require`
macro attribute. While this should be used in most cases, there are also
several instances where you may want to define requirements at runtime,
commonly in plugins.

Example use cases:

- Require components only if the relevant optional plugins are enabled.
For example, a `SleepTimer` component (for physics) is only relevant if
the `SleepPlugin` is enabled.
- Third party crates can define their own requirements for first party
types. For example, "each `Handle<Mesh>` should require my custom
rendering data components". This also gets around the orphan rule.
- Generic plugins that add marker components based on the existence of
other components, like a generic `ColliderPlugin<C: AnyCollider>` that
wants to add a `ColliderMarker` component for all types of colliders.
- This is currently relevant for the retained render world in #15320.
The `ExtractComponentPlugin<C>` should add `SyncToRenderWorld` to all
components that should be extracted. This is currently done with
observers, which is more expensive than required components, and causes
archetype moves.
- Replace some built-in components with custom versions. For example, if
`GlobalTransform` required `Transform` through `TransformPlugin`, but we
wanted to use a `CustomTransform` type, we could replace
`TransformPlugin` with our own plugin. (This specific example isn't
good, but there are likely better use cases where this may be useful)

See #15367 for more in-depth reasoning.

## Solution

Add `register_required_components::<T, R>` and
`register_required_components_with::<T, R>` methods for `Default` and
custom constructors respectively. These methods exist on `App` and
`World`.

```rust
struct BirdPlugin;

impl Plugin for BirdPlugin {
    fn plugin(app: &mut App) {
        // Make `Bird` require `Wings` with a `Default` constructor.
        app.register_required_components::<Bird, Wings>();

        // Make `Wings` require `FlapSpeed` with a custom constructor.
        // Fun fact: Some hummingbirds can flutter their wings 80 times per second!
        app.register_required_components_with::<Wings, FlapSpeed>(|| FlapSpeed::from_duration(1.0 / 80.0));
    }
}
```

The custom constructor is a function pointer to match the `require` API,
though it could take a raw value too.

Requirement inheritance works similarly as with the `require` attribute.
If `Bird` required `FlapSpeed` directly, it would take precedence over
indirectly requiring it through `Wings`. The same logic applies to all
levels of the inheritance tree.

Note that registering the same component requirement more than once will
panic, similarly to trying to add multiple component hooks of the same
type to the same component. This avoids constructor conflicts and
confusing ordering issues.

### Implementation

Runtime requirements have two additional challenges in comparison to the
`require` attribute.

1. The `require` attribute uses recursion and macros with clever
ordering to populate hash maps of required components for each component
type. The expected semantics are that "more specific" requirements
override ones deeper in the inheritance tree. However, at runtime, there
is no representation of how "specific" each requirement is.
2. If you first register the requirement `X -> Y`, and later register `Y
-> Z`, then `X` should also indirectly require `Z`. However, `Y` itself
doesn't know that it is required by `X`, so it's not aware that it
should update the list of required components for `X`.

My solutions to these problems are:

1. Store the depth in the inheritance tree for each entry of a given
component's `RequiredComponents`. This is used to determine how
"specific" each requirement is. For `require`-based registration, these
depths are computed as part of the recursion.
2. Store and maintain a `required_by` list in each component's
`ComponentInfo`, next to `required_components`. For `require`-based
registration, these are also added after each registration, as part of
the recursion.

When calling `register_required_components`, it works as follows:

1. Get the required components of `Foo`, and check that `Bar` isn't
already a *direct* requirement.
3. Register `Bar` as a required component for `Foo`, and add `Foo` to
the `required_by` list for `Bar`.
4. Find and register all indirect requirements inherited from `Bar`,
adding `Foo` to the `required_by` list for each component.
5. Iterate through components that require `Foo`, registering the new
inherited requires for them as indirect requirements.

The runtime registration is likely slightly more expensive than the
`require` version, but it is a one-time cost, and quite negligible in
practice, unless projects have hundreds or thousands of runtime
requirements. I have not benchmarked this however.

This does also add a small amount of extra cost to the `require`
attribute for updating `required_by` lists, but I expect it to be very
minor.

## Testing

I added some tests that are copies of the `require` versions, as well as
some tests that are more specific to the runtime implementation. I might
add a few more tests though.

## Discussion

- Is `register_required_components` a good name? Originally I went for
`register_component_requirement` to be consistent with
`register_component_hooks`, but the general feature is often referred to
as "required components", which is why I changed it to
`register_required_components`.
- Should we *not* panic for duplicate requirements? If so, should they
just be ignored, or should the latest registration overwrite earlier
ones?
- If we do want to panic for duplicate, conflicting registrations,
should we at least not panic if the registrations are *exactly* the
same, i.e. same component and same constructor? The current
implementation panics for all duplicate direct registrations regardless
of the constructor.

## Next Steps

- Allow `register_required_components` to take a `Bundle` instead of a
single required component.
    - I could also try to do it in this PR if that would be preferable.
- Not directly related, but archetype invariants?
2024-09-30 19:20:16 +00:00
Zachary Harrold
d70595b667
Add core and alloc over std Lints (#15281)
# Objective

- Fixes #6370
- Closes #6581

## Solution

- Added the following lints to the workspace:
  - `std_instead_of_core`
  - `std_instead_of_alloc`
  - `alloc_instead_of_core`
- Used `cargo +nightly fmt` with [item level use
formatting](https://rust-lang.github.io/rustfmt/?version=v1.6.0&search=#Item%5C%3A)
to split all `use` statements into single items.
- Used `cargo clippy --workspace --all-targets --all-features --fix
--allow-dirty` to _attempt_ to resolve the new linting issues, and
intervened where the lint was unable to resolve the issue automatically
(usually due to needing an `extern crate alloc;` statement in a crate
root).
- Manually removed certain uses of `std` where negative feature gating
prevented `--all-features` from finding the offending uses.
- Used `cargo +nightly fmt` with [crate level use
formatting](https://rust-lang.github.io/rustfmt/?version=v1.6.0&search=#Crate%5C%3A)
to re-merge all `use` statements matching Bevy's previous styling.
- Manually fixed cases where the `fmt` tool could not re-merge `use`
statements due to conditional compilation attributes.

## Testing

- Ran CI locally

## Migration Guide

The MSRV is now 1.81. Please update to this version or higher.

## Notes

- This is a _massive_ change to try and push through, which is why I've
outlined the semi-automatic steps I used to create this PR, in case this
fails and someone else tries again in the future.
- Making this change has no impact on user code, but does mean Bevy
contributors will be warned to use `core` and `alloc` instead of `std`
where possible.
- This lint is a critical first step towards investigating `no_std`
options for Bevy.

---------

Co-authored-by: François Mockers <francois.mockers@vleue.com>
2024-09-27 00:59:59 +00:00
Clar Fon
efda7f3f9c
Simpler lint fixes: makes ci lints work but disables a lint for now (#15376)
Takes the first two commits from #15375 and adds suggestions from this
comment:
https://github.com/bevyengine/bevy/pull/15375#issuecomment-2366968300

See #15375 for more reasoning/motivation.

## Rebasing (rerunning)

```rust
git switch simpler-lint-fixes
git reset --hard main
cargo fmt --all -- --unstable-features --config normalize_comments=true,imports_granularity=Crate
cargo fmt --all
git add --update
git commit --message "rustfmt"
cargo clippy --workspace --all-targets --all-features --fix
cargo fmt --all -- --unstable-features --config normalize_comments=true,imports_granularity=Crate
cargo fmt --all
git add --update
git commit --message "clippy"
git cherry-pick e6c0b94f6795222310fb812fa5c4512661fc7887
```
2024-09-24 11:42:59 +00:00
Christian Hughes
c7ec456e50
Support systems that take references as input (#15184)
# Objective

- Fixes #14924
- Closes #9584

## Solution

- We introduce a new trait, `SystemInput`, that serves as a type
function from the `'static` form of the input, to its lifetime'd
version, similarly to `SystemParam` or `WorldQuery`.
- System functions now take the lifetime'd wrapped version,
`SystemInput::Param<'_>`, which prevents the issue presented in #14924
(i.e. `InRef<T>`).
- Functions for running systems now take the lifetime'd unwrapped
version, `SystemInput::Inner<'_>` (i.e. `&T`).
- Due to the above change, system piping had to be re-implemented as a
standalone type, rather than `CombinatorSystem` as it was previously.
- Removes the `Trigger<'static, E, B>` transmute in observer runner
code.

## Testing

- All current tests pass.
- Added additional tests and doc-tests.

---

## Showcase

```rust
let mut world = World::new();

let mut value = 2;

// Currently possible:
fn square(In(input): In<usize>) -> usize {
    input * input
}
value = world.run_system_once_with(value, square);

// Now possible:
fn square_mut(InMut(input): InMut<usize>) {
    *input *= *input;
}
world.run_system_once_with(&mut value, square_mut);

// Or:
fn square_ref(InRef(input): InRef<usize>) -> usize {
    *input * *input
}
value = world.run_system_once_with(&value, square_ref);
```

## Migration Guide

- All current explicit usages of the following types must be changed in
the way specified:
    - `SystemId<I, O>` to `SystemId<In<I>, O>`
    - `System<In = T>` to `System<In = In<T>>`
    - `IntoSystem<I, O, M>` to `IntoSystem<In<I>, O, M>`
    - `Condition<M, T>` to `Condition<M, In<T>>`
- `In<Trigger<E, B>>` is no longer a valid input parameter type. Use
`Trigger<E, B>` directly, instead.

---------

Co-authored-by: Giacomo Stevanato <giaco.stevanato@gmail.com>
2024-09-23 17:37:29 +00:00
Rich Churcher
fd329c0426
Allow to expect (adopted) (#15301)
# Objective

> Rust 1.81 released the #[expect(...)] attribute, which works like
#[allow(...)] but throws a warning if the lint isn't raised. This is
preferred to #[allow(...)] because it tells us when it can be removed.

- Adopts the parts of #15118 that are complete, and updates the branch
so it can be merged.
- There were a few conflicts, let me know if I misjudged any of 'em.

Alice's
[recommendation](https://github.com/bevyengine/bevy/issues/15059#issuecomment-2349263900)
seems well-taken, let's do this crate by crate now that @BD103 has done
the lion's share of this!

(Relates to, but doesn't yet completely finish #15059.)

Crates this _doesn't_ cover:

- bevy_input
- bevy_gilrs
- bevy_window
- bevy_winit
- bevy_state
- bevy_render
- bevy_picking
- bevy_core_pipeline
- bevy_sprite
- bevy_text
- bevy_pbr
- bevy_ui
- bevy_gltf
- bevy_gizmos
- bevy_dev_tools
- bevy_internal
- bevy_dylib

---------

Co-authored-by: BD103 <59022059+BD103@users.noreply.github.com>
Co-authored-by: Ben Frankel <ben.frankel7@gmail.com>
Co-authored-by: Antony <antony.m.3012@gmail.com>
2024-09-20 19:16:42 +00:00
Benjamin Brienen
1b8c1c1242
simplify std::mem references (#15315)
# Objective
- Fixes #15314

## Solution

- Remove unnecessary usings and simplify references to those functions.

## Testing

CI
2024-09-19 21:28:16 +00:00
BD103
6ec6a55645
Unify crate-level preludes (#15080)
# Objective

- Crate-level prelude modules, such as `bevy_ecs::prelude`, are plagued
with inconsistency! Let's fix it!

## Solution

Format all preludes based on the following rules:

1. All preludes should have brief documentation in the format of:
   > The _name_ prelude.
   >
> This includes the most common types in this crate, re-exported for
your convenience.
2. All documentation should be outer, not inner. (`///` instead of
`//!`.)
3. No prelude modules should be annotated with `#[doc(hidden)]`. (Items
within them may, though I'm not sure why this was done.)

## Testing

- I manually searched for the term `mod prelude` and updated all
occurrences by hand. 🫠

---------

Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
2024-09-08 17:10:57 +00:00
Alice Cecile
4ac2a63556
Remove all existing system order ambiguities in DefaultPlugins (#15031)
# Objective

As discussed in https://github.com/bevyengine/bevy/issues/7386, system
order ambiguities within `DefaultPlugins` are a source of bugs in the
engine and badly pollute diagnostic output for users.

We should eliminate them!

This PR is an alternative to #15027: with all external ambiguities
silenced, this should be much less prone to merge conflicts and the test
output should be much easier for authors to understand.

Note that system order ambiguities are still permitted in the
`RenderApp`: these need a bit of thought in terms of how to test them,
and will be fairly involved to fix. While these aren't *good*, they'll
generally only cause graphical bugs, not logic ones.

## Solution

All remaining system order ambiguities have been resolved.
Review this PR commit-by-commit to see how each of these problems were
fixed.

## Testing

`cargo run --example ambiguity_detection` passes with no panics or
logging!
2024-09-03 20:24:34 +00:00
Zachary Harrold
bc13161416
Migrated NonZero* to NonZero<*> (#14978)
# Objective

- Fixes #14974

## Solution

- Replace all* instances of `NonZero*` with `NonZero<*>`

## Testing

- CI passed locally.

---

## Notes

Within the `bevy_reflect` implementations for `std` types,
`impl_reflect_value!()` will continue to use the type aliases instead,
as it inappropriately parses the concrete type parameter as a generic
argument. If the `ZeroablePrimitive` trait was stable, or the macro
could be modified to accept a finite list of types, then we could fully
migrate.
2024-08-30 02:37:47 +00:00
Zachary Harrold
6250698b56
Added on_unimplemented Diagnostic for IntoObserverSystem (#14840)
# Objective

- Fixes #14658.

## Solution

- Added `on_unimplemented` Diagnostic for `IntoObserverSystem` calling
out argument ordering in a `note`
- Added an example to the documentation on `App::observe` to provide
some explanation to users.

## Testing

- Ran CI locally
- Deliberately introduced a parameter order error in the
`ecs/observers.rs` example as a test.

---

## Showcase

<details>
  <summary>Error Before</summary>

```
error[E0277]: the trait bound `{closure@examples/ecs/observers.rs:19:13: 22:37}: IntoObserverSystem<_, _, _>` is not satisfied
   --> examples/ecs/observers.rs:19:13
    |
18  |           .observe(
    |            ------- required by a bound introduced by this call
19  | /             |mines: Query<&Mine>,
20  | |             trigger: Trigger<ExplodeMines>,
21  | |             index: Res<SpatialIndex>,
22  | |              mut commands: Commands| {
...   |
34  | |                 }
35  | |             },
    | |_____________^ the trait `bevy::prelude::IntoSystem<bevy::prelude::Trigger<'static, _, _>, (), _>` is not implemented for closure `{closure@examples/ecs/observers.rs:19:13: 22:37}`, which is required by `{closure@examples/ecs/observers.rs:19:13: 22:37}: IntoObserverSystem<_, _, _>`
    |
    = note: required for `{closure@examples/ecs/observers.rs:19:13: 22:37}` to implement `IntoObserverSystem<_, _, _>`
note: required by a bound in `bevy::prelude::App::observe`
   --> C:\Users\Zac\Documents\GitHub\bevy\crates\bevy_app\src\app.rs:995:24
    |
993 |     pub fn observe<E: Event, B: Bundle, M>(
    |            ------- required by a bound in this associated function
994 |         &mut self,
995 |         observer: impl IntoObserverSystem<E, B, M>,
    |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `App::observe`

For more information about this error, try `rustc --explain E0277`.
error: could not compile `bevy` (example "observers") due to 1 previous error
```

</details>

<details>
  <summary>Error After</summary>

```
error[E0277]: `{closure@examples/ecs/observers.rs:19:13: 22:37}` cannot become an `ObserverSystem`
    --> examples/ecs/observers.rs:19:13
     |
18   |           .observe(
     |            ------- required by a bound introduced by this call
19   | /             |mines: Query<&Mine>,
20   | |             trigger: Trigger<ExplodeMines>,
21   | |             index: Res<SpatialIndex>,
22   | |              mut commands: Commands| {
...    |
34   | |                 }
35   | |             },
     | |_____________^ the trait `IntoObserverSystem` is not implemented
     |
     = help: the trait `bevy::prelude::IntoSystem<bevy::prelude::Trigger<'static, _, _>, (), _>` is not implemented for closure `{closure@examples/ecs/observers.rs:19:13: 22:37}`, which is required by `{closure@examples/ecs/observers.rs:19:13: 22:37}: IntoObserverSystem<_, _, _>`
     = note: for function `ObserverSystem`s, ensure the first argument is a `Trigger<T>` and any subsequent ones are `SystemParam`
     = note: required for `{closure@examples/ecs/observers.rs:19:13: 22:37}` to implement `IntoObserverSystem<_, _, _>`
note: required by a bound in `bevy::prelude::App::observe`
    --> C:\Users\Zac\Documents\GitHub\bevy\crates\bevy_app\src\app.rs:1025:24
     |
1023 |     pub fn observe<E: Event, B: Bundle, M>(
     |            ------- required by a bound in this associated function
1024 |         &mut self,
1025 |         observer: impl IntoObserverSystem<E, B, M>,
     |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `App::observe`

For more information about this error, try `rustc --explain E0277`.
error: could not compile `bevy` (example "observers") due to 1 previous error
```

</details>
2024-08-25 14:15:49 +00:00
Jan Hohenheim
c92ee31779
Allow ordering variable timesteps around fixed timesteps (#14881)
# Objective

- Fixes #14873, see that issue for a whole lot of context

## Solution

- Add a blessed system set for this stuff. See [this Discord
discussion](https://discord.com/channels/691052431525675048/749335865876021248/1276262931327094908).

Note that the gizmo systems,
[LWIM](https://github.com/Leafwing-Studios/leafwing-input-manager/pull/522/files#diff-9b59ee4899ad0a5d008889ea89a124a7291316532e42f9f3d6ae842b906fb095R154)
and now a new plugin I'm working on are all already ordering against
`run_fixed_main_schedule`, so having a dedicated system set should be
more robust and hopefully also more discoverable.

---

## ~~Showcase~~

~~I can add a little video of a smooth camera later if this gets merged
:)~~
Apparently a release note is not needed, so I'll leave it out. See the
changes in the fixed timestep example for usage showcase and the video
in #14873 for a more or less accurate video of the effect (it does not
use the same solution though, so it is not quite the same)

## Migration Guide


[run_fixed_main_schedule](https://docs.rs/bevy/latest/bevy/time/fn.run_fixed_main_schedule.html)
is no longer public. If you used to order against it, use the new
dedicated `RunFixedMainLoopSystem` system set instead. You can replace
your usage of `run_fixed_main_schedule` one for one by
`RunFixedMainLoopSystem::FixedMainLoop`, but it is now more idiomatic to
place your systems in either
`RunFixedMainLoopSystem::BeforeFixedMainLoop` or
`RunFixedMainLoopSystem::AfterFixedMainLoop`

Old:
```rust
app.add_systems(
    RunFixedMainLoop,
    some_system.before(run_fixed_main_schedule)
);
```

New:
```rust
app.add_systems(
    RunFixedMainLoop,
    some_system.in_set(RunFixedMainLoopSystem::BeforeFixedMainLoop)
);
```

---------

Co-authored-by: Tau Gärtli <git@tau.garden>
2024-08-23 16:19:42 +00:00
EdJoPaTo
938d810766
Apply unused_qualifications lint (#14828)
# Objective

Fixes #14782

## Solution

Enable the lint and fix all upcoming hints (`--fix`). Also tried to
figure out the false-positive (see review comment). Maybe split this PR
up into multiple parts where only the last one enables the lint, so some
can already be merged resulting in less many files touched / less
potential for merge conflicts?

Currently, there are some cases where it might be easier to read the
code with the qualifier, so perhaps remove the import of it and adapt
its cases? In the current stage it's just a plain adoption of the
suggestions in order to have a base to discuss.

## Testing

`cargo clippy` and `cargo run -p ci` are happy.
2024-08-21 12:29:33 +00:00
Gino Valente
2b4180ca8f
bevy_reflect: Function reflection terminology refactor (#14813)
# Objective

One of the changes in #14704 made `DynamicFunction` effectively the same
as `DynamicClosure<'static>`. This change meant that the de facto
function type would likely be `DynamicClosure<'static>` instead of the
intended `DynamicFunction`, since the former is much more flexible.

We _could_ explore ways of making `DynamicFunction` implement `Copy`
using some unsafe code, but it likely wouldn't be worth it. And users
would likely still reach for the convenience of
`DynamicClosure<'static>` over the copy-ability of `DynamicFunction`.

The goal of this PR is to fix this confusion between the two types.

## Solution

Firstly, the `DynamicFunction` type was removed. Again, it was no
different than `DynamicClosure<'static>` so it wasn't a huge deal to
remove.

Secondly, `DynamicClosure<'env>` and `DynamicClosureMut<'env>` were
renamed to `DynamicFunction<'env>` and `DynamicFunctionMut<'env>`,
respectively.

Yes, we still ultimately kept the naming of `DynamicFunction`, but
changed its behavior to that of `DynamicClosure<'env>`. We need a term
to refer to both functions and closures, and "function" was the best
option.


[Originally](https://discord.com/channels/691052431525675048/1002362493634629796/1274091992162242710),
I was going to go with "callable" as the replacement term to encompass
both functions and closures (e.g. `DynamciCallable<'env>`). However, it
was
[suggested](https://discord.com/channels/691052431525675048/1002362493634629796/1274653581777047625)
by @SkiFire13 that the simpler "function" term could be used instead.

While "callable" is perhaps the better umbrella term—being truly
ambiguous over functions and closures— "function" is more familiar, used
more often, easier to discover, and is subjectively just
"better-sounding".

## Testing

Most changes are purely swapping type names or updating documentation,
but you can verify everything still works by running the following
command:

```
cargo test --package bevy_reflect
```
2024-08-19 21:52:36 +00:00
Gino Valente
423285cf1c
bevy_reflect: Store functions as DynamicClosure<'static> in FunctionRegistry (#14704)
# Objective

#14098 added the `FunctionRegistry` for registering functions such that
they can be retrieved by name and used dynamically. One thing we chose
to leave out in that initial PR is support for closures.

Why support closures? Mainly, we don't want to prohibit users from
injecting environmental data into their registered functions. This
allows these functions to not leak their internals to the public API.

For example, let's say we're writing a library crate that allows users
to register callbacks for certain actions. We want to perform some
actions before invoking the user's callback so we can't just call it
directly. We need a closure for this:

```rust
registry.register("my_lib::onclick", move |event: ClickEvent| {
    // ...other work...

    user_onclick.call(event); // <-- Captured variable
});
```

We could have made our callback take a reference to the user's callback.
This would remove the need for the closure, but it would change our
desired API to place the burden of fetching the correct callback on the
caller.

## Solution

Modify the `FunctionRegistry` to store registered functions as
`DynamicClosure<'static>` instead of `DynamicFunction` (now using
`IntoClosure` instead of `IntoFunction`).

Due to limitations in Rust and how function reflection works,
`DynamicClosure<'static>` is functionally equivalent to
`DynamicFunction`. And a normal function is considered a subset of
closures (it's a closure that doesn't capture anything), so there
shouldn't be any difference in usage: all functions that satisfy
`IntoFunction` should satisfy `IntoClosure`.

This means that the registration API introduced in #14098 should require
little-to-no changes on anyone following `main`.

### Closures vs Functions

One consideration here is whether we should keep closures and functions
separate.

This PR unifies them into `DynamicClosure<'static>`, but we can consider
splitting them up. The reasons we might want to do so are:

- Simplifies mental model and terminology (users don't have to
understand that functions turn into closures)
- If Rust ever improves its function model, we may be able to add
additional guarantees to `DynamicFunction` that make it useful to
separate the two
- Adding support for generic functions may be less confusing for users
since closures in Rust technically can't be generic

The reasons behind this PR's unification approach are:

- Reduces the number of methods needed on `FunctionRegistry`
- Reduces the number of lookups a user may have to perform (i.e.
"`get_function` or else `get_closure`")
- Establishes `DynamicClosure<'static>` as the de facto dynamic callable
(similar to how most APIs in Rust code tend to prefer `impl Fn() ->
String` over `fn() -> String`)

I'd love to hear feedback on this matter, and whether we should continue
with this PR's approach or switch to a split model.

## Testing

You can test locally by running:

```
cargo test --package bevy_reflect
```

---

## Showcase

Closures can now be registered into the `FunctionRegistry`:

```rust
let punct = String::from("!!!");

registry.register_with_name("my_crate::punctuate", move |text: String| {
  format!("{}{}", text, punct)
});
```
2024-08-17 00:20:47 +00:00
Gino Valente
a0cc636ea3
bevy_reflect: Anonymous function parsing (#14641)
# Objective

### TL;DR

#14098 added the `FunctionRegistry` but had some last minute
complications due to anonymous functions. It ended up going with a
"required name" approach to ensure anonymous functions would always have
a name.

However, this approach isn't ideal for named functions since, by
definition, they will always have a name.

Therefore, this PR aims to modify function reflection such that we can
make function registration easier for named functions, while still
allowing anonymous functions to be registered as well.

### Context

Function registration (#14098) ran into a little problem: anonymous
functions.

Anonymous functions, including function pointers, have very non-unique
type names. For example, the anonymous function `|a: i32, b: i32| a + b`
has the type name of `fn(i32, i32) -> i32`. This obviously means we'd
conflict with another function like `|a: i32, b: i32| a - b`.

The solution that #14098 landed on was to always require a name during
function registration.

The downside with this is that named functions (e.g. `fn add(a: i32, b:
i32) -> i32 { a + b }`) had to redundantly provide a name. Additionally,
manually constructed `DynamicFunction`s also ran into this ergonomics
issue.

I don't entirely know how the function registry will be used, but I have
a strong suspicion that most of its registrations will either be named
functions or manually constructed `DynamicFunction`s, with anonymous
functions only being used here and there for quick prototyping or adding
small functionality.

Why then should the API prioritize the anonymous function use case by
always requiring a name during registration?

#### Telling Functions Apart

Rust doesn't provide a lot of out-of-the-box tools for reflecting
functions. One of the biggest hurdles in attempting to solve the problem
outlined above would be to somehow tell the different kinds of functions
apart.

Let's briefly recap on the categories of functions in Rust:

| Category           | Example                                   |
| ------------------ | ----------------------------------------- |
| Named function     | `fn add(a: i32, b: i32) -> i32 { a + b }` |
| Closure            | `\|a: i32\| a + captured_variable`          |
| Anonymous function | `\|a: i32, b: i32\| a + b`                  |
| Function pointer   | `fn(i32, i32) -> i32`                     |

My first thought was to try and differentiate these categories based on
their size. However, we can see that this doesn't quite work:

| Category           | `size_of` |
| ------------------ | --------- |
| Named function     | 0         |
| Closure            | 0+        |
| Anonymous function | 0         |
| Function pointer   | 8         |

Not only does this not tell anonymous functions from named ones, but it
struggles with pretty much all of them.

My second then was to differentiate based on type name:

| Category           | `type_name`             |
| ------------------ | ----------------------- |
| Named function     | `foo::bar::baz`         |
| Closure            | `foo::bar::{{closure}}` |
| Anonymous function | `fn() -> String`        |
| Function pointer   | `fn() -> String`        |

This is much better. While it can't distinguish between function
pointers and anonymous functions, this doesn't matter too much since we
only care about whether we can _name_ the function.

So why didn't we implement this in #14098?

#### Relying on `type_name`

While this solution was known about while working on #14098, it was left
out from that PR due to it being potentially controversial.

The [docs](https://doc.rust-lang.org/stable/std/any/fn.type_name.html)
for `std::any::type_name` state:

> The returned string must not be considered to be a unique identifier
of a type as multiple types may map to the same type name. Similarly,
there is no guarantee that all parts of a type will appear in the
returned string: for example, lifetime specifiers are currently not
included. In addition, the output may change between versions of the
compiler.

So that's it then? We can't use `type_name`?

Well, this statement isn't so much a rule as it is a guideline. And Bevy
is no stranger to bending the rules to make things work or to improve
ergonomics. Remember that before `TypePath`, Bevy's scene system was
entirely dependent on `type_name`. Not to mention that `type_name` is
being used as a key into both the `TypeRegistry` and the
`FunctionRegistry`.

Bevy's practices aside, can we reliably use `type_name` for this?

My answer would be "yes".

Anonymous functions are anonymous. They have no name. There's nothing
Rust could do to give them a name apart from generating a random string
of characters. But remember that this is a diagnostic tool, it doesn't
make sense to obfuscate the type by randomizing the output. So changing
it to be anything other than what it is now is very unlikely.

The only changes that I could potentially see happening are:

1. Closures replace `{{closure}}` with the name of their variable
2. Lifetimes are included in the output

I don't think the first is likely to happen, but if it does then it
actually works out in our favor: closures are now named!

The second point is probably the likeliest. However, adding lifetimes
doesn't mean we can't still rely on `type_name` to determine whether or
not a function is named. So we should be okay in this case as well.

## Solution

Parse the `type_name` of the function in the `TypedFunction` impl to
determine if the function is named or anonymous.

This once again makes `FunctionInfo::name` optional. For manual
constructions of `DynamicFunction`, `FunctionInfo::named` or
``FunctionInfo::anonymous` can be used.

The `FunctionRegistry` API has also been reworked to account for this
change.

`FunctionRegistry::register` no longer takes a name and instead takes it
from the supplied function, returning a
`FunctionRegistrationError::MissingName` error if the name is `None`.
This also doubles as a replacement for the old
`FunctionRegistry::register_dynamic` method, which has been removed.

To handle anonymous functions, a `FunctionRegistry::register_with_name`
method has been added. This works in the same way
`FunctionRegistry::register` used to work before this PR.

The overwriting methods have been updated in a similar manner, with
modifications to `FunctionRegistry::overwrite_registration`, the removal
of `FunctionRegistry::overwrite_registration_dynamic`, and the addition
of `FunctionRegistry::overwrite_registration_with_name`.

This PR also updates the methods on `App` in a similar way:
`App::register_function` no longer requires a name argument and
`App::register_function_with_name` has been added to handle anonymous
functions (and eventually closures).

## Testing

You can run the tests locally by running:

```
cargo test --package bevy_reflect --features functions
```

---

## Internal Migration Guide

> [!important]
> Function reflection was introduced as part of the 0.15 dev cycle. This
migration guide was written for developers relying on `main` during this
cycle, and is not a breaking change coming from 0.14.

> [!note]
> This list is not exhaustive. It only contains some of the most
important changes.

`FunctionRegistry::register` no longer requires a name string for named
functions. Anonymous functions, however, need to be registered using
`FunctionRegistry::register_with_name`.

```rust
// BEFORE
registry
  .register(std::any::type_name_of_val(&foo), foo)?
  .register("bar", || println!("Hello world!"));

// AFTER
registry
  .register(foo)?
  .register_with_name("bar", || println!("Hello world!"));
```

`FunctionInfo::name` is now optional. Anonymous functions and closures
will now have their name set to `None` by default. Additionally,
`FunctionInfo::new` has been renamed to `FunctionInfo::named`.
2024-08-07 03:11:08 +00:00
Christian Hughes
039bf90817
Improve documentation on Update vs FixedUpdate schedule dichotomy (#14600)
# Objective

When looking at documentation for the `Update` schedule, its not
entirely obvious that developers should actually be using the
`FixedUpdate` schedule for most of their game logic. We should directly
cross-link between the two, and give examples of which systems to put in
which schedules.

## Solution

Do just that.
2024-08-06 01:26:37 +00:00
Gino Valente
df61117850
bevy_reflect: Function registry (#14098)
# Objective

#13152 added support for reflecting functions. Now, we need a way to
register those functions such that they may be accessed anywhere within
the ECS.

## Solution

Added a `FunctionRegistry` type similar to `TypeRegistry`.

This allows a function to be registered and retrieved by name.

```rust
fn foo() -> i32 {
    123
}

let mut registry = FunctionRegistry::default();
registry.register("my_function", foo);

let function = registry.get_mut("my_function").unwrap();
let value = function.call(ArgList::new()).unwrap().unwrap_owned();
assert_eq!(value.downcast_ref::<i32>(), Some(&123));
```

Additionally, I added an `AppFunctionRegistry` resource which wraps a
`FunctionRegistryArc`. Functions can be registered into this resource
using `App::register_function` or by getting a mutable reference to the
resource itself.

### Limitations

#### `Send + Sync`

In order to get this registry to work across threads, it needs to be
`Send + Sync`. This means that `DynamicFunction` needs to be `Send +
Sync`, which means that its internal function also needs to be `Send +
Sync`.

In most cases, this won't be an issue because standard Rust functions
(the type most likely to be registered) are always `Send + Sync`.
Additionally, closures tend to be `Send + Sync` as well, granted they
don't capture any `!Send` or `!Sync` variables.

This PR adds this `Send + Sync` requirement, but as mentioned above, it
hopefully shouldn't be too big of an issue.

#### Closures

Unfortunately, closures can't be registered yet. This will likely be
explored and added in a followup PR.

### Future Work

Besides addressing the limitations listed above, another thing we could
look into is improving the lookup of registered functions. One aspect is
in the performance of hashing strings. The other is in the developer
experience of having to call `std::any::type_name_of_val` to get the
name of their function (assuming they didn't give it a custom name).

## Testing

You can run the tests locally with:

```
cargo test --package bevy_reflect
```

---

## Changelog

- Added `FunctionRegistry`
- Added `AppFunctionRegistry` (a `Resource` available from `bevy_ecs`)
- Added `FunctionRegistryArc`
- Added `FunctionRegistrationError`
- Added `reflect_functions` feature to `bevy_ecs` and `bevy_app`
- `FunctionInfo` is no longer `Default`
- `DynamicFunction` now requires its wrapped function be `Send + Sync`

## Internal Migration Guide

> [!important]
> Function reflection was introduced as part of the 0.15 dev cycle. This
migration guide was written for developers relying on `main` during this
cycle, and is not a breaking change coming from 0.14.

`DynamicFunction` (both those created manually and those created with
`IntoFunction`), now require `Send + Sync`. All standard Rust functions
should meet that requirement. Closures, on the other hand, may not if
they capture any `!Send` or `!Sync` variables from its environment.
2024-08-06 01:09:48 +00:00
Jan Hohenheim
6f7c554daa
Fix common capitalization errors in documentation (#14562)
WASM -> Wasm
MacOS -> macOS

Nothing important, just something that annoyed me for a while :)
2024-07-31 21:16:05 +00:00
BD103
d722fef23d
Remove deprecated bevy_dynamic_plugin (#14534)
# Objective

- Dynamic plugins were deprecated in #13080 due to being unsound. The
plan was to deprecate them in 0.14 and remove them in 0.15.

## Solution

- Remove all dynamic plugin functionality.
- Update documentation to reflect this change.

---

## Migration Guide

Dynamic plugins were deprecated in 0.14 for being unsound, and they have
now been fully removed. Please consider using the alternatives listed in
the `bevy_dynamic_plugin` crate documentation, or worst-case scenario
you may copy the code from 0.14.
2024-07-30 15:31:08 +00:00
Giacomo Stevanato
71c5f1e3e4
Generate links to definition in source code pages on docs.rs and dev-docs.bevyengine.org (#12965)
# Objective

- Fix issue #2611

## Solution

- Add `--generate-link-to-definition` to all the `rustdoc-args` arrays
in the `Cargo.toml`s (for docs.rs)
- Add `--generate-link-to-definition` to the `RUSTDOCFLAGS` environment
variable in the docs workflow (for dev-docs.bevyengine.org)
- Document all the workspace crates in the docs workflow (needed because
otherwise only the source code of the `bevy` package will be included,
making the argument useless)
- I think this also fixes #3662, since it fixes the bug on
dev-docs.bevyengine.org, while on docs.rs it has been fixed for a while
on their side.

---

## Changelog

- The source code viewer on docs.rs now includes links to the
definitions.
2024-07-29 23:10:16 +00:00