bevy/crates/bevy_tasks
BD103 bc98333d7c
Fix a few Clippy lints (#11866)
# Objective

- The current implementations for `&Visibility == Visibility` and
`Visibility == &Visibility` are ambiguous, so they raise a warning for
being unconditionally recursive.
- `TaskPool`'s `LOCAL_EXECUTOR` thread local calls a `const` constructor
in a non-`const` context.

## Solution

- Make `&Visibility == Visibility` and `Visibility == &Visibility`
implementations use `Visibility == Visibility`.
- Wrap `LocalExecutor::new` in a special `const` block supported by
[`thread_local`](https://doc.rust-lang.org/stable/std/macro.thread_local.html).

---

This lints were found by running:

```shell
$ cargo clippy --workspace
```

There are a few other warnings that were more complicated, so I chose
not to include them in this PR.

<details>
  <summary>Here they are...</summary>

```shell
warning: function cannot return without recursing
  --> crates/bevy_utils/src/cow_arc.rs:92:5
   |
92 | /     fn eq(&self, other: &Self) -> bool {
93 | |         self.deref().eq(other.deref())
94 | |     }
   | |_____^
   |
note: recursive call site
  --> crates/bevy_utils/src/cow_arc.rs:93:9
   |
93 |         self.deref().eq(other.deref())
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

warning: method `get_path` is never used
  --> crates/bevy_reflect/src/serde/de.rs:26:8
   |
25 | trait StructLikeInfo {
   |       -------------- method in this trait
26 |     fn get_path(&self) -> &str;
   |        ^^^^^^^^
   |
   = note: `#[warn(dead_code)]` on by default

warning: methods `get_path` and `get_field` are never used
  --> crates/bevy_reflect/src/serde/de.rs:34:8
   |
33 | trait TupleLikeInfo {
   |       ------------- methods in this trait
34 |     fn get_path(&self) -> &str;
   |        ^^^^^^^^
35 |     fn get_field(&self, index: usize) -> Option<&UnnamedField>;
   |        ^^^^^^^^^
```

The other warnings are fixed by #11865.

</details>
2024-02-14 19:07:18 +00:00
..
examples Inverse missing_docs logic (#11676) 2024-02-03 21:40:55 +00:00
src Fix a few Clippy lints (#11866) 2024-02-14 19:07:18 +00:00
Cargo.toml Async channel v2 (#10692) 2024-01-15 19:23:00 +00:00
README.md add and fix shields in Readmes (#9993) 2023-10-15 00:52:31 +00:00

Bevy Tasks

License Crates.io Downloads Docs Discord

A refreshingly simple task executor for bevy. :)

This is a simple threadpool with minimal dependencies. The main usecase is a scoped fork-join, i.e. spawning tasks from a single thread and having that thread await the completion of those tasks. This is intended specifically for bevy as a lighter alternative to rayon for this specific usecase. There are also utilities for generating the tasks from a slice of data. This library is intended for games and makes no attempt to ensure fairness or ordering of spawned tasks.

It is based on async-executor, a lightweight executor that allows the end user to manage their own threads. async-executor is based on async-task, a core piece of async-std.

Usage

In order to be able to optimize task execution in multi-threaded environments, bevy provides three different thread pools via which tasks of different kinds can be spawned. (The same API is used in single-threaded environments, even if execution is limited to a single thread. This currently applies to WASM targets.) The determining factor for what kind of work should go in each pool is latency requirements:

  • For CPU-intensive work (tasks that generally spin until completion) we have a standard [ComputeTaskPool] and an [AsyncComputeTaskPool]. Work that does not need to be completed to present the next frame should go to the [AsyncComputeTaskPool].

  • For IO-intensive work (tasks that spend very little time in a "woken" state) we have an [IoTaskPool] whose tasks are expected to complete very quickly. Generally speaking, they should just await receiving data from somewhere (i.e. disk) and signal other systems when the data is ready for consumption. (likely via channels)