Commit Graph

380 Commits

Author SHA1 Message Date
Zhixing Zhang
f2a65c2dd3
Schedule build pass (#11094)
# Objective

This is a follow up to #9822, which automatically adds sync points
during the Schedule build process.

However, the implementation in #9822 feels very "special case" to me. As
the number of things we want to do with the `Schedule` grows, we need a
modularized way to manage those behaviors. For example, in one of my
current experiments I want to automatically add systems to apply GPU
pipeline barriers between systems accessing GPU resources.

For dynamic modifications of the schedule, we mostly need these
capabilities:
- Storing custom data on schedule edges
- Storing custom data on schedule nodes
- Modify the schedule graph whenever it builds

These should be enough to allows us to add "hooks" to the schedule build
process for various reasons.

cc @hymm 

## Solution
This PR abstracts the process of schedule modification and created a new
trait, `ScheduleBuildPass`. Most of the logics in #9822 were moved to an
implementation of `ScheduleBuildPass`, `AutoInsertApplyDeferredPass`.

Whether a dependency edge should "ignore deferred" is now indicated by
the presence of a marker struct, `IgnoreDeferred`.

This PR has no externally visible effects. However, in a future PR I
propose to change the `before_ignore_deferred` and
`after_ignore_deferred` API into a more general form,
`before_with_options` and `after_with_options`.

```rs
schedule.add_systems(
    system.before_with_options(another_system, IgnoreDeferred)
);

schedule.add_systems(
    system.before_with_options(another_system, (
        IgnoreDeferred,
        AnyOtherOption {
            key: value
        }
    ))
);

schedule.add_systems(
    system.before_with_options(another_system, ())
);
```
2025-02-05 23:14:05 +00:00
Zachary Harrold
9bc0ae33c3
Move hashbrown and foldhash out of bevy_utils (#17460)
# Objective

- Contributes to #16877

## Solution

- Moved `hashbrown`, `foldhash`, and related types out of `bevy_utils`
and into `bevy_platform_support`
- Refactored the above to match the layout of these types in `std`.
- Updated crates as required.

## Testing

- CI

---

## Migration Guide

- The following items were moved out of `bevy_utils` and into
`bevy_platform_support::hash`:
  - `FixedState`
  - `DefaultHasher`
  - `RandomState`
  - `FixedHasher`
  - `Hashed`
  - `PassHash`
  - `PassHasher`
  - `NoOpHash`
- The following items were moved out of `bevy_utils` and into
`bevy_platform_support::collections`:
  - `HashMap`
  - `HashSet`
- `bevy_utils::hashbrown` has been removed. Instead, import from
`bevy_platform_support::collections` _or_ take a dependency on
`hashbrown` directly.
- `bevy_utils::Entry` has been removed. Instead, import from
`bevy_platform_support::collections::hash_map` or
`bevy_platform_support::collections::hash_set` as appropriate.
- All of the above equally apply to `bevy::utils` and
`bevy::platform_support`.

## Notes

- I left `PreHashMap`, `PreHashMapExt`, and `TypeIdMap` in `bevy_utils`
as they might be candidates for micro-crating. They can always be moved
into `bevy_platform_support` at a later date if desired.
2025-01-23 16:46:08 +00:00
Alice Cecile
44ad3bf62b
Move Resource trait to its own file (#17469)
# Objective

`bevy_ecs`'s `system` module is something of a grab bag, and *very*
large. This is particularly true for the `system_param` module, which is
more than 2k lines long!

While it could be defensible to put `Res` and `ResMut` there (lol no
they're in change_detection.rs, obviously), it doesn't make any sense to
put the `Resource` trait there. This is confusing to navigate (and
painful to work on and review).

## Solution

- Create a root level `bevy_ecs/resource.rs` module to mirror
`bevy_ecs/component.rs`
- move the `Resource` trait to that module
- move the `Resource` derive macro to that module as well (Rust really
likes when you pun on the names of the derive macro and trait and put
them in the same path)
- fix all of the imports

## Notes to reviewers

- We could probably move more stuff into here, but I wanted to keep this
PR as small as possible given the absurd level of import changes.
- This PR is ground work for my upcoming attempts to store resource data
on components (resources-as-entities). Splitting this code out will make
the work and review a bit easier, and is the sort of overdue refactor
that's good to do as part of more meaningful work.

## Testing

cargo build works!

## Migration Guide

`bevy_ecs::system::Resource` has been moved to
`bevy_ecs::resource::Resource`.
2025-01-21 19:47:08 +00:00
SpecificProtagonist
a7051a4815
Diagnostics for label traits (#17441)
# Objective

Diagnostics for labels don't suggest how to best implement them.
```
error[E0277]: the trait bound `Label: ScheduleLabel` is not satisfied
   --> src/main.rs:15:35
    |
15  |     let mut sched = Schedule::new(Label);
    |                     ------------- ^^^^^ the trait `ScheduleLabel` is not implemented for `Label`
    |                     |
    |                     required by a bound introduced by this call
    |
    = help: the trait `ScheduleLabel` is implemented for `Interned<(dyn ScheduleLabel + 'static)>`
note: required by a bound in `bevy_ecs::schedule::Schedule::new`
   --> /home/vj/workspace/rust/bevy/crates/bevy_ecs/src/schedule/schedule.rs:297:28
    |
297 |     pub fn new(label: impl ScheduleLabel) -> Self {
    |                            ^^^^^^^^^^^^^ required by this bound in `Schedule::new`
```

## Solution

`diagnostics::on_unimplemented` and `diagnostics::do_not_recommend`

## Showcase

New error message:
```
error[E0277]: the trait bound `Label: ScheduleLabel` is not satisfied
   --> src/main.rs:15:35
    |
15  |     let mut sched = Schedule::new(Label);
    |                     ------------- ^^^^^ the trait `ScheduleLabel` is not implemented for `Label`
    |                     |
    |                     required by a bound introduced by this call
    |
    = note: consider annotating `Label` with `#[derive(ScheduleLabel)]`
note: required by a bound in `bevy_ecs::schedule::Schedule::new`
   --> /home/vj/workspace/rust/bevy/crates/bevy_ecs/src/schedule/schedule.rs:297:28
    |
297 |     pub fn new(label: impl ScheduleLabel) -> Self {
    |                            ^^^^^^^^^^^^^ required by this bound in `Schedule::new`
```
2025-01-20 21:51:26 +00:00
Zachary Harrold
a64446b77e
Create bevy_platform_support Crate (#17250)
# Objective

- Contributes to #16877

## Solution

- Initial creation of `bevy_platform_support` crate.
- Moved `bevy_utils::Instant` into new `bevy_platform_support` crate.
- Moved `portable-atomic`, `portable-atomic-util`, and
`critical-section` into new `bevy_platform_support` crate.

## Testing

- CI

---

## Showcase

Instead of needing code like this to import an `Arc`:

```rust
#[cfg(feature = "portable-atomic")]
use portable_atomic_util::Arc;

#[cfg(not(feature = "portable-atomic"))]
use alloc::sync::Arc;
```

We can now use:

```rust
use bevy_platform_support::sync::Arc;
```

This applies to many other types, but the goal is overall the same:
allowing crates to use `std`-like types without the boilerplate of
conditional compilation and platform-dependencies.

## Migration Guide

- Replace imports of `bevy_utils::Instant` with
`bevy_platform_support::time::Instant`
- Replace imports of `bevy::utils::Instant` with
`bevy::platform_support::time::Instant`

## Notes

- `bevy_platform_support` hasn't been reserved on `crates.io`
- ~~`bevy_platform_support` is not re-exported from `bevy` at this time.
It may be worthwhile exporting this crate, but I am unsure of a
reasonable name to export it under (`platform_support` may be a bit
wordy for user-facing).~~
- I've included an implementation of `Instant` which is suitable for
`no_std` platforms that are not Wasm for the sake of eliminating feature
gates around its use. It may be a controversial inclusion, so I'm happy
to remove it if required.
- There are many other items (`spin`, `bevy_utils::Sync(Unsafe)Cell`,
etc.) which should be added to this crate. I have kept the initial scope
small to demonstrate utility without making this too unwieldy.

---------

Co-authored-by: TimJentzsch <TimJentzsch@users.noreply.github.com>
Co-authored-by: Chris Russell <8494645+chescock@users.noreply.github.com>
Co-authored-by: François Mockers <francois.mockers@vleue.com>
2025-01-20 20:45:30 +00:00
Christian Hughes
14a955c5eb
Add usage notes for the IntoX family of ECS traits (#17379)
# Objective

Occasionally bevy users will want to store systems or observer systems
in a component or resource, but they first try to store `IntoSystem`
instead of `System`, which leads to some headaches having to deal with
the `M` marker type parameter. We should recommend they use the `X`
trait instead of the `IntoX` trait in that case, as well for returning
from a function.

## Solution

Add usage notes to the `IntoX` traits about using `X` instead.
2025-01-17 01:18:22 +00:00
Jaso333
9ef1964d34
added any_match_filter common condition (#17327)
# Objective

resolves #17326.

## Solution

Simply added the suggested run condition.

## Testing

A self-explanatory run condition. Fully verified by the operation of
`QueryFilter` in a system.
2025-01-14 21:53:35 +00:00
MichiRecRoom
17c46f4add
bevy_ecs: Apply #![warn(clippy::allow_attributes, clippy::allow_attributes_without_reason)] (#17335)
# Objective
- https://github.com/bevyengine/bevy/issues/17111

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

## Testing
This PR is a WIP; testing will happen after it's finished.
2025-01-14 21:37:41 +00:00
AlephCubed
e808fbe987
Renamed members of ParamWarnPolicy to reflect new behaviour. (#17311)
- `Once` renamed to `Warn`.
- `param_warn_once()` renamed to `warn_param_missing()`.
- `never_param_warn()` renamed to `ignore_param_missing()`.

Also includes changes to the documentation of the above methods.

Fixes #17262.

## Migration Guide
- `ParamWarnPolicy::Once` has been renamed to `ParamWarnPolicy::Warn`.
- `ParamWarnPolicy::param_warn_once` has been renamed to
`ParamWarnPolicy::warn_param_missing`.
- `ParamWarnPolicy::never_param_warn` has been renamed to
`ParamWarnPolicy::ignore_param_missing`.
2025-01-12 05:40:04 +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
Rob Parrett
651b22f31f
Update typos (#17126)
# Objective

Use the latest version of `typos` and fix the typos that it now detects

# Additional Info

By the way, `typos` has a "low priority typo suggestions issue" where we
can throw typos we find that `typos` doesn't catch.

(This link may go stale) https://github.com/crate-ci/typos/issues/1200
2025-01-03 17:44:26 +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
arunke
22bf3b9a62
Fix documentation for system set method (#17106)
# Objective

Fix incorrect comment on `IntoSystemSetConfigs::after` likely caused by
copy-paste error. It said "before" instead of "after".

## Solution

Update the comment to the correct text.

## Testing

CI tests pass. This is just updating a comment.
2025-01-02 22:38:26 +00:00
Mike
ac43d5c94f
Convert to fallible system in IntoSystemConfigs (#17051)
# Objective

- #16589 added an enum to switch between fallible and infallible system.
This branching should be unnecessary if we wrap infallible systems in a
function to return `Ok(())`.

## Solution

- Create a wrapper system for `System<(), ()>`s that returns `Ok` on the
call to `run` and `run_unsafe`. The wrapper should compile out, but I
haven't checked.
- I removed the `impl IntoSystemConfigs for BoxedSystem<(), ()>` as I
couldn't figure out a way to keep the impl without double boxing.

## Testing

- ran `many_foxes` example to check if it still runs.

## Migration Guide

- `IntoSystemConfigs` has been removed for `BoxedSystem<(), ()>`. Either
use `InfallibleSystemWrapper` before boxing or make your system return
`bevy::ecs::prelude::Result`.
2024-12-31 00:39:29 +00:00
Zhixing Zhang
9cebc66486
Make 8 methods public and updated input parameter generics for SystemState::build_system_with_input (#17034)
# Objective

- Made certain methods public for advanced use cases. Methods that
returns mutable references are marked as unsafe due to the possibility
of violating internal lifetime constraint assumptions.
- Fixes an issue introduced by #15184
2024-12-30 23:04:14 +00:00
Vic
b78efd339d
Simplify sort/max_by calls (#17048)
# Objective

Some sort calls and `Ord` impls are unnecessarily complex.

## Solution

Rewrite the "match on cmp, if equal do another cmp" as either a
comparison on tuples, or `Ordering::then_with`, depending on whether the
compare keys need construction.

`sort_by` -> `sort_by_key` when symmetrical. Do the same for
`min_by`/`max_by`.

Note that `total_cmp` can only work with `sort_by`, and not on tuples.

When sorting collected query results that contain
`Entity`/`MainEntity`/`RenderEntity` in their `QueryData`, with that
`Entity` in the sort key:
stable -> unstable sort (all queried entities are unique)

If key construction is not simple, switch to `sort_by_cached_key` when
possible.

Sorts that are only performed to discover the maximal element are
replaced by `max_by_key`.

Dedicated comparison functions and structs are removed where simple.

Derive `PartialOrd`/`Ord` when useful.

Misc. closure style inconsistencies.

## Testing
- Existing tests.
2024-12-30 22:59:36 +00:00
François Mockers
394e82f4bc
panic on system error (#16979)
# Objective

- First step for #16718 
- #16589 introduced an api that can only ignore errors, which is risky

## Solution

- Panic instead of just ignoring the errors

## Testing

- Changed the `fallible_systems` example to return an error
```
Encountered an error in system `fallible_systems::setup`: TooManyVertices { subdivisions: 300, number_of_resulting_points: 906012 }
Encountered a panic in system `fallible_systems::setup`!
Encountered a panic in system `bevy_app::main_schedule::Main::run_main`!
```
2024-12-26 23:44:46 +00:00
Benjamin Brienen
1675d68366
Fix beta CI (#16984)
# Objective

Fixes #16607

## Solution

Satisfy clippy

## Testing

Ran clippy
2024-12-26 22:17:51 +00:00
MiniaczQ
460de77a55
Set panic as default fallible system param behavior (#16638)
# Objective

Fixes: #16578

## Solution

This is a patch fix, proper fix requires a breaking change.

Added `Panic` enum variant and using is as the system meta default.
Warn once behavior can be enabled same way disabling panic (originally
disabling wans) is.

To fix an issue with the current architecture, where **all** combinator
system params get checked together,
combinator systems only check params of the first system.
This will result in old, panicking behavior on subsequent systems and
will be fixed in 0.16.

## Testing

Ran unit tests and `fallible_params` example.

---------

Co-authored-by: François Mockers <mockersf@gmail.com>
Co-authored-by: François Mockers <francois.mockers@vleue.com>
2024-12-24 02:36:03 +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
1f2d0e6308
Add no_std support to bevy_ecs (#16758)
# Objective

- Contributes to #15460

## Solution

- Added the following features:
  - `std` (default)
  - `async_executor` (default)
  - `edge_executor`
  - `critical-section`
  - `portable-atomic`
- Gated `tracing` in `bevy_utils` to allow compilation on certain
platforms
- Switched from `tracing` to `log` for simple message logging within
`bevy_ecs`. Note that `tracing` supports capturing from `log` so this
should be an uncontroversial change.
- Fixed imports and added feature gates as required 
- Made `bevy_tasks` optional within `bevy_ecs`. Turns out it's only
needed for parallel operations which are already gated behind
`multi_threaded` anyway.

## Testing

- Added to `compile-check-no-std` CI command
- `cargo check -p bevy_ecs --no-default-features --features
edge_executor,critical-section,portable-atomic --target
thumbv6m-none-eabi`
- `cargo check -p bevy_ecs --no-default-features --features
edge_executor,critical-section`
- `cargo check -p bevy_ecs --no-default-features`

## Draft Release Notes

Bevy's core ECS now supports `no_std` platforms.

In prior versions of Bevy, it was not possible to work with embedded or
niche platforms due to our reliance on the standard library, `std`. This
has blocked a number of novel use-cases for Bevy, such as an embedded
database for IoT devices, or for creating games on retro consoles.

With this release, `bevy_ecs` no longer requires `std`. To use Bevy on a
`no_std` platform, you must disable default features and enable the new
`edge_executor` and `critical-section` features. You may also need to
enable `portable-atomic` and `critical-section` if your platform does
not natively support all atomic types and operations used by Bevy.

```toml
[dependencies]
bevy_ecs = { version = "0.16", default-features = false, features = [
  # Required for platforms with incomplete atomics (e.g., Raspberry Pi Pico)
  "portable-atomic",
  "critical-section",

  # Optional
  "bevy_reflect",
  "serialize",
  "bevy_debug_stepping",
  "edge_executor"
] }
```

Currently, this has been tested on bare-metal x86 and the Raspberry Pi
Pico. If you have trouble using `bevy_ecs` on a particular platform,
please reach out either through a GitHub issue or in the `no_std`
working group on the Bevy Discord server.

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

- Creating PR in draft to ensure CI is passing before requesting
reviews.
- This implementation has no support for multithreading in `no_std`,
especially due to `NonSend` being unsound if allowed in multithreading.
The reason is we cannot check the `ThreadId` in `no_std`, so we have no
mechanism to at-runtime determine if access is sound.

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Vic <59878206+Victoronz@users.noreply.github.com>
2024-12-17 21:40:36 +00:00
Christian Hughes
cc0f6a8db4
Remove deprecated ECS items (#16853)
# Objective

- Cleanup deprecated code

## Solution

- Removed `#[deprecated]` items which were marked as such in 0.15 or
prior versions.

## Migration Guide

- The following deprecated items were removed: `Events::get_reader`,
`Events::get_reader_current`, `ManualEventReader`,
`Condition::and_then`, `Condition::or_else`, `World::,many_entities`,
`World::many_entities_mut`, `World::get_many_entities`,
`World::get_many_entities_dynamic`, `World::get_many_entities_mut`,
`World::get_many_entities_dynamic_mut`,
`World::get_many_entities_from_set_mut`
2024-12-17 05:43:05 +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
homersimpsons
0707c0717b
✏️ Fix typos across bevy (#16702)
# Objective

Fixes typos in bevy project, following suggestion in
https://github.com/bevyengine/bevy-website/pull/1912#pullrequestreview-2483499337

## Solution

I used https://github.com/crate-ci/typos to find them.

I included only the ones that feel undebatable too me, but I am not in
game engine so maybe some terms are expected.

I left out the following typos:
- `reparametrize` => `reparameterize`: There are a lot of occurences, I
believe this was expected
- `semicircles` => `hemicircles`: 2 occurences, may mean something
specific in geometry
- `invertation` => `inversion`: may mean something specific
- `unparented` => `parentless`: may mean something specific
- `metalness` => `metallicity`: may mean something specific

## Testing

- Did you test these changes? If so, how? I did not test the changes,
most changes are related to raw text. I expect the others to be tested
by the CI.
- Are there any parts that need more testing? I do not think
- How can other people (reviewers) test your changes? Is there anything
specific they need to know? To me there is nothing to test
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?

---

## Migration Guide

> This section is optional. If there are no breaking changes, you can
delete this section.

(kept in case I include the `reparameterize` change here)

- If this PR is a breaking change (relative to the last release of
Bevy), describe how a user might need to migrate their code to support
these changes
- Simply adding new functionality is not a breaking change.
- Fixing behavior that was definitely a bug, rather than a questionable
design choice is not a breaking change.

## Questions

- [x] Should I include the above typos? No
(https://github.com/bevyengine/bevy/pull/16702#issuecomment-2525271152)
- [ ] Should I add `typos` to the CI? (I will check how to configure it
properly)

This project looks awesome, I really enjoy reading the progress made,
thanks to everyone involved.
2024-12-08 01:18:39 +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
Miles Silberling-Cook
0070514f54
Fallible systems (#16589)
# Objective

Error handling in bevy is hard. See for reference
https://github.com/bevyengine/bevy/issues/11562,
https://github.com/bevyengine/bevy/issues/10874 and
https://github.com/bevyengine/bevy/issues/12660. The goal of this PR is
to make it better, by allowing users to optionally return `Result` from
systems as outlined by Cart in
<https://github.com/bevyengine/bevy/issues/14275#issuecomment-2223708314>.

## Solution

This PR introduces a new `ScheuleSystem` type to represent systems that
can be added to schedules. Instances of this type contain either an
infallible `BoxedSystem<(), ()>` or a fallible `BoxedSystem<(),
Result>`. `ScheuleSystem` implements `System<In = (), Out = Result>` and
replaces all uses of `BoxedSystem` in schedules. The async executor now
receives a result after executing a system, which for infallible systems
is always `Ok(())`. Currently it ignores this result, but more useful
error handling could also be implemented.

Aliases for `Error` and `Result` have been added to the `bevy_ecs`
prelude, as well as const `OK` which new users may find more friendly
than `Ok(())`.

## Testing

- Currently there are not actual semantics changes that really require
new tests, but I added a basic one just to make sure we don't break
stuff in the future.
- The behavior of existing systems is totally unchanged, including
logging.
- All of the existing systems tests pass, and I have not noticed
anything strange while playing with the examples

## Showcase

The following minimal example prints "hello world" once, then completes.

```rust
use bevy::prelude::*;

fn main() {
    App::new().add_systems(Update, hello_world_system).run();
}

fn hello_world_system() -> Result {
    println!("hello world");
    Err("string")?;
    println!("goodbye world");
    OK
}
```

## Migration Guide

This change should be pretty much non-breaking, except for users who
have implemented their own custom executors. Those users should use
`ScheduleSystem` in place of `BoxedSystem<(), ()>` and import the
`System` trait where needed. They can choose to do whatever they wish
with the result.

## Current Work

+ [x] Fix tests & doc comments
+ [x] Write more tests
+ [x] Add examples
+ [X] Draft release notes

## Draft Release Notes

As of this release, systems can now return results.

First a bit of background: Bevy has hisotrically expected systems to
return the empty type `()`. While this makes sense in the context of the
ecs, it's at odds with how error handling is typically done in rust:
returning `Result::Error` to indicate failure, and using the
short-circuiting `?` operator to propagate that error up the call stack
to where it can be properly handled. Users of functional languages will
tell you this is called "monadic error handling".

Not being able to return `Results` from systems left bevy users with a
quandry. They could add custom error handling logic to every system, or
manually pipe every system into an error handler, or perhaps sidestep
the issue with some combination of fallible assignents, logging, macros,
and early returns. Often, users would just litter their systems with
unwraps and possible panics.

While any one of these approaches might be fine for a particular user,
each of them has their own drawbacks, and none makes good use of the
language. Serious issues could also arrise when two different crates
used by the same project made different choices about error handling.

Now, by returning results, systems can defer error handling to the
application itself. It looks like this:

```rust
// Previous, handling internally
app.add_systems(my_system)
fn my_system(window: Query<&Window>) {
   let Ok(window) = query.get_single() else {
       return;
   };
   // ... do something to the window here
}

// Previous, handling externally
app.add_systems(my_system.pipe(my_error_handler))
fn my_system(window: Query<&Window>) -> Result<(), impl Error> {
   let window = query.get_single()?;
   // ... do something to the window here
   Ok(())
}

// Previous, panicking
app.add_systems(my_system)
fn my_system(window: Query<&Window>) {
   let window = query.single();
   // ... do something to the window here
}

// Now 
app.add_systems(my_system)
fn my_system(window: Query<&Window>) -> Result {
    let window = query.get_single()?;
    // ... do something to the window here
    Ok(())
}
```

There are currently some limitations. Systems must either return `()` or
`Result<(), Box<dyn Error + Send + Sync + 'static>>`, with no
in-between. Results are also ignored by default, and though implementing
a custom handler is possible, it involves writing your own custom ecs
executor (which is *not* recomended).

Systems should return errors when they cannot perform their normal
behavior. In turn, errors returned to the executor while running the
schedule will (eventually) be treated as unexpected. Users and library
authors should prefer to return errors for anything that disrupts the
normal expected behavior of a system, and should only handle expected
cases internally.

We have big plans for improving error handling further:
+ Allowing users to change the error handling logic of the default
executors.
+ Adding source tracking and optional backtraces to errors.
+ Possibly adding tracing-levels (Error/Warn/Info/Debug/Trace) to
errors.
+ Generally making the default error logging more helpful and
inteligent.
+ Adding monadic system combininators for fallible systems.
+ Possibly removing all panicking variants from our api.

---------

Co-authored-by: Zachary Harrold <zac@harrold.com.au>
2024-12-05 22:29:06 +00:00
Christian Hughes
f87b9fe20c
Turn apply_deferred into a ZST System (#16642)
# Objective

- Required by #16622 due to differing implementations of `System` by
`FunctionSystem` and `ExclusiveFunctionSystem`.
- Optimize the memory usage of instances of `apply_deferred` in system
schedules.

## Solution

By changing `apply_deferred` from being an ordinary system that ends up
as an `ExclusiveFunctionSystem`, and instead into a ZST struct that
implements `System` manually, we save ~320 bytes per instance of
`apply_deferred` in any schedule.

## Testing

- All current tests pass.

---

## Migration Guide

- If you were previously calling the special `apply_deferred` system via
`apply_deferred(world)`, don't.
2024-12-05 18:14:05 +00:00
Zachary Harrold
c9fa975977
Remove petgraph from bevy_ecs (#15519)
# Objective

- Contributes to #15460

## Solution

- Removed `petgraph` as a dependency from the `bevy_ecs` crate.
- Replaced `TarjanScc` and `GraphMap` with specialised in-tree
alternatives.

## Testing

- Ran CI locally.
- Added new unit tests to check ordering invariants.
- Confirmed `petgraph` is no longer present in `cargo tree -p bevy_ecs`

## Migration Guide

The `Dag::graph` method no longer returns a `petgraph` `DiGraph` and
instead returns the new `DiGraph` type within `bevy_ecs`. Edge and node
iteration methods are provided so conversion to the `petgraph` type
should be trivial if required.

## Notes

- `indexmap` was already in the dependency graph for `bevy_ecs`, so its
inclusion here makes no difference to compilation time for Bevy.
- The implementation for `Graph` is heavily inspired from the `petgraph`
original, with specialisations added to simplify and improve the type.
- `petgraph` does have public plans for `no_std` support, however there
is no timeframe on if or when that functionality will be available.
Moving to an in-house solution in the interim allows Bevy to continue
developing its `no_std` offerings and further explore alternate graphing
options.

---------

Co-authored-by: Lixou <82600264+DasLixou@users.noreply.github.com>
Co-authored-by: vero <11307157+atlv24@users.noreply.github.com>
2024-12-03 20:01:55 +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
Zachary Harrold
d143da338a
Fixed issue with derive_more Display Implementations (#16298)
# Objective

- Fixed issue where `thiserror` `#[error(...)]` attributes were
improperly converted to `derive_more` `#[display(...)]` equivalents in
certain cases with a tuple struct/enum variant.

## Solution

- Used `re/#\[display\(.*\{[0-9]+\}.*\)\]/` to find occurences of using
`{0}` where `{_0}` was intended (checked for other field indexes too)and
updated accordingly.

## Testing

- `cargo check`
- CI

## Notes

This was discovered by @dtolnay in [this
comment](https://github.com/bevyengine/bevy/pull/15772#discussion_r1833730555).
2024-11-08 20:29:52 +00:00
urben1680
1e47604506
Adding ScheduleGraph::contains_set (#16206)
# Objective

The schedule graph can easily confirm whether a set is contained or not.

This helps me in my personal project where I write an extension trait
for `Schedule` and I want to configure a specific set in its methods.
The set in question has a run condition though and I don't want to add
that condition to the same schedule as many times as the trait methods
are called. Since the non-pub set is unknown to the schedule until then,
a `contains_set` is sufficient.

It is probably trivial to add a method that returns an `Option<NodeId>`
as well but as I personally don't need it I did not add that. If it is
desired I can do so here though. It might be unneeded to have a
`contains_set` then because one could check `is_some` on the returned id
in that case.

An argument against that is that future changes may be easier if only a
`contains_set` needs to be ported.

## Solution

Added `ScheduleGraph::contains_set`.

## Testing

I put the below showcase code into a temporary unit test and it worked.
If wanted I add it as a test too but I did not see that other more
somewhat complicated methods have tests

---

## Showcase

```rs
#[derive(ScheduleLabel, Debug, Default, Clone, Copy, PartialEq, Eq, Hash)]
struct MySchedule;

#[derive(SystemSet, Debug, Default, Clone, Copy, PartialEq, Eq, Hash)]
struct MySet;

let mut schedule = Schedule::new(MySchedule);
assert_eq!(schedule.graph().contains_set(MySet), false);
schedule.configure_sets(MySet);
assert_eq!(schedule.graph().contains_set(MySet), true);
```
2024-11-03 16:16:24 +00:00
Rob Parrett
30d84519a2
Use en-us locale for typos (#16037)
# Objective

Bevy seems to want to standardize on "American English" spellings. Not
sure if this is laid out anywhere in writing, but see also #15947.

While perusing the docs for `typos`, I noticed that it has a `locale`
config option and tried it out.

## Solution

Switch to `en-us` locale in the `typos` config and run `typos -w`

## Migration Guide

The following methods or fields have been renamed from `*dependants*` to
`*dependents*`.

- `ProcessorAssetInfo::dependants`
- `ProcessorAssetInfos::add_dependant`
- `ProcessorAssetInfos::non_existent_dependants`
- `AssetInfo::dependants_waiting_on_load`
- `AssetInfo::dependants_waiting_on_recursive_dep_load`
- `AssetInfos::loader_dependants`
- `AssetInfos::remove_dependants_and_labels`
2024-10-20 18:55:17 +00:00
Christian Hughes
b4071ca370
Add World::get_resource_or_init as an alternative to World::get_resource_or_insert_with (#15758)
# Objective

If a `Resource` implements `FromWorld` or `Default`, it's nicer to be
able to write:

```rust
let foo = world.get_resource_or_init::<Foo>();
```

Rather than:

```rust
let foo = world.get_resource_or_insert_with(Foo::default);
```

The latter is also not possible if a type implements `FromWorld` only,
and not `Default`.

## Solution

Added:

```rust
impl World {
    pub fn get_resource_or_init<R: Resource + FromWorld>(&mut self) -> Mut<'_, R>;
}
```

Turns out all current in-engine uses of `get_resource_or_insert_with`
are exactly the above, so they've also been replaced.

## Testing

- Added a doc-test.
- Also added a doc-test for `World::get_resource_or_insert_with`.
2024-10-09 20:56:26 +00:00
Zachary Harrold
0a61f04d9b
Remove thiserror from bevy_ecs (#15774)
# Objective

- Contributes to #15460

## Solution

- Removed `thiserror` from `bevy_ecs`
2024-10-09 14:20:58 +00:00
MiniaczQ
acea4e7e6f
Better warnings about invalid parameters (#15500)
# Objective

System param validation warnings should be configurable and default to
"warn once" (per system).

Fixes: #15391

## Solution

`SystemMeta` is given a new `ParamWarnPolicy` field.
The policy decides whether warnings will be emitted by each system param
when it fails validation.
The policy is updated by the system after param validation fails.

Example warning:
```
2024-09-30T18:10:04.740749Z  WARN bevy_ecs::system::function_system: System fallible_params::do_nothing_fail_validation will not run because it requested inaccessible system parameter Single<(), (With<Player>, With<Enemy>)>
```

Currently, only the first invalid parameter is displayed.

Warnings can be disabled on function systems using
`.param_never_warn()`.
(there is also `.with_param_warn_policy(policy)`)

## Testing

Ran `fallible_params` example.

---------

Co-authored-by: SpecificProtagonist <vincentjunge@posteo.net>
2024-10-03 13:16:55 +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
hshrimp
35d10866b8
Rename init_component & friends (#15454)
# Objective

- Fixes #15451 

## Migration Guide

- `World::init_component` has been renamed to `register_component`.
- `World::init_component_with_descriptor` has been renamed to
`register_component_with_descriptor`.
- `World::init_bundle` has been renamed to `register_bundle`.
- `Components::init_component` has been renamed to `register_component`.
- `Components::init_component_with_descriptor` has been renamed to
`register_component_with_descriptor`.
- `Components::init_resource` has been renamed to `register_resource`.
- `Components::init_non_send` had been renamed to `register_non_send`.
2024-09-26 22:47:28 +00:00
Giacomo Stevanato
fb9aaa1527
Follow up to cached run_system (#15410)
# Objective

- Fixes #15373
- Fixes
https://github.com/bevyengine/bevy/pull/14920#issuecomment-2370428013

## Solution

- Make `IntoSystem::pipe` and `IntoSystem::map` return two new
(possibly-ZST) types that implement `IntoSystem` and whose `into_system`
method return the systems that were previously being returned by
`IntoSystem::pipe` and `IntoSystem::map`
- Don't eagerly call `IntoSystem::into_system` on the argument given to
`RunSystemCachedWith::new` to avoid losing its ZST-ness

## Testing

- Added a regression test for each issue

## Migration Guide

- `IntoSystem::pipe` and `IntoSystem::map` now return `IntoPipeSystem`
and `IntoAdapterSystem` instead of `PipeSystem` and `AdapterSystem`.
Most notably these types don't implement `System` but rather only
`IntoSystem`.
2024-09-24 17:35:44 +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
MiniaczQ
740d1cc9ff
Fix system param warnings on systems that cannot run anyways (#15397)
# Objective

Fix "system skipped" warnings when validation fails on systems that
wouldn't run because of run conditions.

## Solution

> I think the error is from a system defined as:
> 
> ```rust
> no_gpu_preprocessing::batch_and_prepare_sorted_render_phase::<SPI,
GFBD>
> .run_if(resource_exists::<BatchedInstanceBuffer<GFBD::BufferData>>),
> ```
> 
> So the `run_if` was preventing the panics. Maybe we need to skip
validation if `!system_conditions_met`, or at least silence the warning
in that case.

*By @chescock in
https://discord.com/channels/691052431525675048/692572690833473578/1287865365312831562*

Validation of system is skipped if the system was already skipped by run
conditions.

## Testing

Ran alien addict example, no more warnings.
2024-09-23 20:25:49 +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
Benjamin Brienen
8a6d0b063c
Use crate: disqualified (#15372)
# Objective

Fixes #15351 

## Solution

- Created new external crate and ported over the code

## Testing

- CI

## Migration guide

Replace references to `bevy_utils::ShortName` with
`disqualified::ShortName`.
2024-09-23 17:34:17 +00:00
MiniaczQ
e312da8c52
Reduce runtime panics through SystemParam validation (#15276)
# Objective

The goal of this PR is to introduce `SystemParam` validation in order to
reduce runtime panics.

Fixes #15265

## Solution

`SystemParam` now has a new method `validate_param(...) -> bool`, which
takes immutable variants of `get_param` arguments. The returned value
indicates whether the parameter can be acquired from the world. If
parameters cannot be acquired for a system, it won't be executed,
similarly to run conditions. This reduces panics when using params like
`Res`, `ResMut`, etc. as well as allows for new, ergonomic params like
#15264 or #15302.

Param validation happens at the level of executors. All validation
happens directly before executing a system, in case of normal systems
they are skipped, in case of conditions they return false.

Warning about system skipping is primitive and subject to change in
subsequent PRs.

## Testing

Two executor tests check that all executors:
- skip systems which have invalid parameters:
  - piped systems get skipped together,
  - dependent systems still run correctly,
- skip systems with invalid run conditions:
  - system conditions have invalid parameters,
  - system set conditions have invalid parameters.
2024-09-23 16:54:21 +00:00
Benjamin Brienen
02a9ed4b0b
move ShortName to bevy_reflect (#15340)
# Objective

- Goal is to minimize bevy_utils #11478

## Solution

- Move the file short_name wholesale into bevy_reflect

## Testing

- Unit tests
- CI

## Migration Guide

- References to `bevy_utils::ShortName` should instead now be
`bevy_reflect::ShortName`.

---------

Co-authored-by: François Mockers <francois.mockers@vleue.com>
2024-09-21 20:52:46 +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
Giacomo Stevanato
106db47f69
Fix subtle/weird UB in the multi threaded executor (#15309)
# Objective

- The multithreaded executor has some weird UB related to stacked
borrows and async blocks
- See my explanation on discord
https://discord.com/channels/691052431525675048/749335865876021248/1286359267921887232
- Closes #15296 (can this be used to close PRs?)

## Solution

- Don't create a `&mut World` reference outside `async` blocks and then
capture it, but instead directly create it inside the `async` blocks.
This avoids it being captured, which has some weird requirement on its
validity.

## Testing

- Added a regression test
2024-09-19 18:15:58 +00:00
Zachary Harrold
fcfa60844a
Remove allocation in get_short_name (#15294)
`ShortName` is lazily evaluated and does not allocate, instead providing
`Display` and `Debug` implementations which write directly to a
formatter using the original algorithm. When using `ShortName` in format
strings (`panic`, `dbg`, `format`, etc.) you can directly use the
`ShortName` type. If you require a `String`, simply call
`ShortName(...).to_string()`.

# Objective

- Remove the requirement for allocation when using `get_short_name`

## Solution

- Added new type `ShortName` which wraps a name and provides its own
`Debug` and `Display` implementations, using the original
`get_short_name` algorithm without the need for allocating.
- Removed `get_short_name`, as `ShortName(...)` is more performant and
ergonomic.
- Added `ShortName::of::<T>` method to streamline the common use-case
for name shortening.

## Testing

- CI

## Migration Guide

### For `format!`, `dbg!`, `panic!`, etc.

```rust
// Before
panic!("{} is too short!", get_short_name(name));

// After
panic!("{} is too short!", ShortName(name));
```

### Need a `String` Value

```rust
// Before
let short: String = get_short_name(name);

// After
let short: String = ShortName(name).to_string();
```

## Notes

`ShortName` lazily evaluates, and directly writes to a formatter via
`Debug` and `Display`, which removes the need to allocate a `String`
when printing a shortened type name. Because the implementation has been
moved into the `fmt` method, repeated printing of the `ShortName` type
may be less performant than converting it into a `String`. However, no
instances of this are present in Bevy, and the user can get the original
behaviour by calling `.to_string()` at no extra cost.

---------

Co-authored-by: Gino Valente <49806985+MrGVSV@users.noreply.github.com>
2024-09-19 15:34:03 +00:00
Christian Hughes
378dcacf82
Group IntoSystemConfigs impls together (#15254)
# Objective

Two of the `IntoSystemConfigs` `impl`s are out of place near the top of
the file.

## Solution

Put them below the `IntoSystemConfigs` trait definition, alongside the
other `impl`.
2024-09-17 17:57:22 +00:00
kivi
3f425da66e
Improve schedule note of .after/.before & encourage to use .chain ins… (#14986)
# Objective

- Fixes #14552 
- Make the current note of `before` and `after` understandable. 
- > The given set is not implicitly added to the schedule when this
system set is added.

## Solution

- Replace note in docs of [`after` and
`before`](https://docs.rs/bevy/latest/bevy/ecs/prelude/trait.IntoSystemConfigs.html#method.before)
- Note of after was removed completely, and links to `before`, because
they notes would be identical.
- Also encourage to use `.chain`, which is much simpler and safer to use

## Testing

- Checked the docs after running `cargo doc` and `cargo run -p ci --
lints`
- Are there any parts that need more testing?
- no need to test, but please review the text. If it is still including
the intended message and especially if its understandable.

---------

Co-authored-by: Jan Hohenheim <jan@hohenheim.ch>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-09-14 21:03:21 +00:00
Alix Bott
12f005a024
Add condition_changed and condition_became_true to common_conditions (#14917)
# Objective

- I needed to run a system whenever a specific condition became true
after being previously false.
- Other users might also need to run a system when a condition changes,
regardless of if it became true or false.

## Solution

- This adds two systems to common_conditions:
- `condition_changed` that changes whenever the inner condition changes
- `condition_became_true` that returns true whenever the inner condition
becomes true after previously being false

## Testing

- I added a doctest for each function

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Jan Hohenheim <jan@hohenheim.ch>
2024-08-26 18:32:44 +00:00