Objective
During work on #3009 I've found that not all jobs use actions-rs, and therefore, an previous version of Rust is used for them. So while compilation and other stuff can pass, checking markup and Android build may fail with compilation errors.
Solution
This PR adds `action-rs` for any job running cargo, and updates the edition to 2021.
# Objective
- Avoid usages of `format!` that ~immediately get passed to another `format!`. This avoids a temporary allocation and is just generally cleaner.
## Solution
- `bevy_derive::shader_defs` does a `format!("{}", val.to_string())`, which is better written as just `format!("{}", val)`
- `bevy_diagnostic::log_diagnostics_plugin` does a `format!("{:>}", format!(...))`, which is better written as `format!("{:>}", format_args!(...))`
- `bevy_ecs::schedule` does `tracing::info!(..., name = &*format!("{:?}", val))`, which is better written with the tracing shorthand `tracing::info!(..., name = ?val)`
- `bevy_reflect::reflect` does `f.write_str(&format!(...))`, which is better written as `write!(f, ...)` (this could also be written using `f.debug_tuple`, but I opted to maintain alt debug behavior)
- `bevy_reflect::serde::{ser, de}` do `serde::Error::custom(format!(...))`, which is better written as `Error::custom(format_args!(...))`, as `Error::custom` takes `impl Display` and just immediately calls `format!` again
## Objective
- Clean up remaining references to the trait `FromResources`, which was replaced in favor of `FromWorld` during the ECS rework.
## Solution
- Remove the derive macro for `FromResources`
- Change doc references of `FromResources` to `FromWorld`
(this is the first item in #2576)
# Objective
Reduce compilation time
# Solution
Remove unused dependencies. While this PR doesn't remove any crates from `Cargo.lock`, it may unlock more build parallelism.
Problem:
- When using the 'as_crate' attribute, if 'as_crate' was empty, the only
error you would get is 'integer underflow'.
Solution:
- Provide an explicit check for the 'as_crate' attribute's token stream
to ensure the formatting is correct.
Note:
- Also reworked 'get_meta' by not making it call 'Manifest::find' twice.
Fixes#2037 (and then some)
Problem:
- `TypeUuid`, `RenderResource`, and `Bytes` derive macros did not properly handle generic structs.
Solution:
- Rework the derive macro implementations to handle the generics.
There are cases where we want an enum variant name. Right now the only way to do that with rust's std is to derive Debug, but this will also print out the variant's fields. This creates the unfortunate situation where we need to manually write out each variant's string name (ex: in #1963), which is both boilerplate-ey and error-prone. Crates such as `strum` exist for this reason, but it includes a lot of code and complexity that we don't need.
This adds a dead-simple `EnumVariantMeta` derive that exposes `enum_variant_index` and `enum_variant_name` functions. This allows us to make cases like #1963 much cleaner (see the second commit). We might also be able to reuse this logic for `bevy_reflect` enum derives.
