# 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_tasks` 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.
# 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
# Objective
- Contributes to #15460
## Solution
- Added the following features:
- `std` (default)
- `async_executor` (default)
- `edge_executor`
- `critical-section`
- `portable-atomic`
- Added [`edge-executor`](https://crates.io/crates/edge-executor) as a
`no_std` alternative to `async-executor`.
- Updated the `single_threaded_task_pool` to work in `no_std`
environments by gating its reliance on `thread_local`.
## Testing
- Added to `compile-check-no-std` CI command
## Notes
- In previous iterations of this PR, a custom `async-executor`
alternative was vendored in. This raised concerns around maintenance and
testing. In this iteration, an existing version of that same vendoring
is now used, but _only_ in `no_std` contexts. For existing `std`
contexts, the original `async-executor` is used.
- Due to the way statics work, certain `TaskPool` operations have added
restrictions around `Send`/`Sync` in `no_std`. This is because there
isn't a straightforward way to create a thread-local in `no_std`. If
these added constraints pose an issue we can revisit this at a later
date.
- If a user enables both the `async_executor` and `edge_executor`
features, we will default to using `async-executor`. Since enabling
`async_executor` requires `std`, we can safely assume we are in an `std`
context and use the original library.
---------
Co-authored-by: Mike <2180432+hymm@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
