bevy/crates/bevy_utils/src/once.rs
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

63 lines
1.6 KiB
Rust

/// Call some expression only once per call site.
#[macro_export]
macro_rules! once {
($expression:expr) => {{
use ::core::sync::atomic::{AtomicBool, Ordering};
static SHOULD_FIRE: AtomicBool = AtomicBool::new(true);
if SHOULD_FIRE.swap(false, Ordering::Relaxed) {
$expression;
}
}};
}
/// Call [`trace!`](crate::tracing::trace) once per call site.
///
/// Useful for logging within systems which are called every frame.
#[macro_export]
macro_rules! trace_once {
($($arg:tt)+) => ({
$crate::once!($crate::tracing::trace!($($arg)+))
});
}
/// Call [`debug!`](crate::tracing::debug) once per call site.
///
/// Useful for logging within systems which are called every frame.
#[macro_export]
macro_rules! debug_once {
($($arg:tt)+) => ({
$crate::once!($crate::tracing::debug!($($arg)+))
});
}
/// Call [`info!`](crate::tracing::info) once per call site.
///
/// Useful for logging within systems which are called every frame.
#[macro_export]
macro_rules! info_once {
($($arg:tt)+) => ({
$crate::once!($crate::tracing::info!($($arg)+))
});
}
/// Call [`warn!`](crate::tracing::warn) once per call site.
///
/// Useful for logging within systems which are called every frame.
#[macro_export]
macro_rules! warn_once {
($($arg:tt)+) => ({
$crate::once!($crate::tracing::warn!($($arg)+))
});
}
/// Call [`error!`](crate::tracing::error) once per call site.
///
/// Useful for logging within systems which are called every frame.
#[macro_export]
macro_rules! error_once {
($($arg:tt)+) => ({
$crate::once!($crate::tracing::error!($($arg)+))
});
}