bevy/tools/ci/src/main.rs
Gino Valente 56686a8962
bevy_derive: Add #[deref] attribute (#8552)
# Objective

Bevy code tends to make heavy use of the [newtype](
https://doc.rust-lang.org/rust-by-example/generics/new_types.html)
pattern, which is why we have a dedicated derive for
[`Deref`](https://doc.rust-lang.org/std/ops/trait.Deref.html) and
[`DerefMut`](https://doc.rust-lang.org/std/ops/trait.DerefMut.html).
This derive works for any struct with a single field:

```rust
#[derive(Component, Deref, DerefMut)]
struct MyNewtype(usize);
```

One reason for the single-field limitation is to prevent confusion and
footguns related that would arise from allowing multi-field structs:

<table align="center">
<tr>
<th colspan="2">
Similar structs, different derefs
</th>
</tr>
<tr>
<td>

```rust
#[derive(Deref, DerefMut)]
struct MyStruct {
  foo: usize, // <- Derefs usize
  bar: String,
}
```

</td>
<td>

```rust
#[derive(Deref, DerefMut)]
struct MyStruct {
  bar: String, // <- Derefs String
  foo: usize,
}
```

</td>
</tr>
<tr>
<th colspan="2">
Why `.1`?
</th>
</tr>
<tr>
<td colspan="2">

```rust
#[derive(Deref, DerefMut)]
struct MyStruct(Vec<usize>, Vec<f32>);

let mut foo = MyStruct(vec![123], vec![1.23]);

// Why can we skip the `.0` here?
foo.push(456);
// But not here?
foo.1.push(4.56);
```

</td>
</tr>
</table>

However, there are certainly cases where it's useful to allow for
structs with multiple fields. Such as for structs with one "real" field
and one `PhantomData` to allow for generics:

```rust
#[derive(Deref, DerefMut)]
struct MyStruct<T>(
  // We want use this field for the `Deref`/`DerefMut` impls
  String,
  // But we need this field so that we can make this struct generic
  PhantomData<T>
);

// ERROR: Deref can only be derived for structs with a single field
// ERROR: DerefMut can only be derived for structs with a single field
```

Additionally, the possible confusion and footguns are mainly an issue
for newer Rust/Bevy users. Those familiar with `Deref` and `DerefMut`
understand what adding the derive really means and can anticipate its
behavior.

## Solution

Allow users to opt into multi-field `Deref`/`DerefMut` derives using a
`#[deref]` attribute:

```rust
#[derive(Deref, DerefMut)]
struct MyStruct<T>(
  // Use this field for the `Deref`/`DerefMut` impls
  #[deref] String,
  // We can freely include any other field without a compile error
  PhantomData<T>
);
```

This prevents the footgun pointed out in the first issue described in
the previous section, but it still leaves the possible confusion
surrounding `.0`-vs-`.#`. However, the idea is that by making this
behavior explicit with an attribute, users will be more aware of it and
can adapt appropriately.

---

## Changelog

- Added `#[deref]` attribute to `Deref` and `DerefMut` derives
2023-05-16 18:29:09 +00:00

167 lines
5.9 KiB
Rust

use xshell::{cmd, Shell};
use bitflags::bitflags;
bitflags! {
struct Check: u32 {
const FORMAT = 0b00000001;
const CLIPPY = 0b00000010;
const COMPILE_FAIL = 0b00000100;
const TEST = 0b00001000;
const DOC_TEST = 0b00010000;
const DOC_CHECK = 0b00100000;
const BENCH_CHECK = 0b01000000;
const EXAMPLE_CHECK = 0b10000000;
const COMPILE_CHECK = 0b100000000;
}
}
const CLIPPY_FLAGS: [&str; 8] = [
"-Aclippy::type_complexity",
"-Wclippy::doc_markdown",
"-Wclippy::redundant_else",
"-Wclippy::match_same_arms",
"-Wclippy::semicolon_if_nothing_returned",
"-Wclippy::explicit_iter_loop",
"-Wclippy::map_flatten",
"-Dwarnings",
];
fn main() {
// When run locally, results may differ from actual CI runs triggered by
// .github/workflows/ci.yml
// - Official CI runs latest stable
// - Local runs use whatever the default Rust is locally
let arguments = [
("lints", Check::FORMAT | Check::CLIPPY),
("test", Check::TEST),
("doc", Check::DOC_TEST | Check::DOC_CHECK),
(
"compile",
Check::COMPILE_FAIL | Check::BENCH_CHECK | Check::EXAMPLE_CHECK | Check::COMPILE_CHECK,
),
("format", Check::FORMAT),
("clippy", Check::CLIPPY),
("compile-fail", Check::COMPILE_FAIL),
("bench-check", Check::BENCH_CHECK),
("example-check", Check::EXAMPLE_CHECK),
("doc-check", Check::DOC_CHECK),
("doc-test", Check::DOC_TEST),
];
let what_to_run = if let Some(arg) = std::env::args().nth(1).as_deref() {
if let Some((_, check)) = arguments.iter().find(|(str, _)| *str == arg) {
*check
} else {
println!(
"Invalid argument: {arg:?}.\nEnter one of: {}.",
arguments[1..]
.iter()
.map(|(s, _)| s)
.fold(arguments[0].0.to_owned(), |c, v| c + ", " + v)
);
return;
}
} else {
Check::all()
};
let sh = Shell::new().unwrap();
if what_to_run.contains(Check::FORMAT) {
// See if any code needs to be formatted
cmd!(sh, "cargo fmt --all -- --check")
.run()
.expect("Please run 'cargo fmt --all' to format your code.");
}
if what_to_run.contains(Check::CLIPPY) {
// See if clippy has any complaints.
// - Type complexity must be ignored because we use huge templates for queries
cmd!(
sh,
"cargo clippy --workspace --all-targets --all-features -- {CLIPPY_FLAGS...}"
)
.run()
.expect("Please fix clippy errors in output above.");
}
if what_to_run.contains(Check::COMPILE_FAIL) {
{
// ECS Compile Fail Tests
// Run UI tests (they do not get executed with the workspace tests)
// - See crates/bevy_ecs_compile_fail_tests/README.md
let _subdir = sh.push_dir("crates/bevy_ecs_compile_fail_tests");
cmd!(sh, "cargo test --target-dir ../../target")
.run()
.expect("Compiler errors of the ECS compile fail tests seem to be different than expected! Check locally and compare rust versions.");
}
{
// Reflect Compile Fail Tests
// Run tests (they do not get executed with the workspace tests)
// - See crates/bevy_reflect_compile_fail_tests/README.md
let _subdir = sh.push_dir("crates/bevy_reflect_compile_fail_tests");
cmd!(sh, "cargo test --target-dir ../../target")
.run()
.expect("Compiler errors of the Reflect compile fail tests seem to be different than expected! Check locally and compare rust versions.");
}
{
// Macro Compile Fail Tests
// Run tests (they do not get executed with the workspace tests)
// - See crates/bevy_macros_compile_fail_tests/README.md
let _subdir = sh.push_dir("crates/bevy_macros_compile_fail_tests");
cmd!(sh, "cargo test --target-dir ../../target")
.run()
.expect("Compiler errors of the macros compile fail tests seem to be different than expected! Check locally and compare rust versions.");
}
}
if what_to_run.contains(Check::TEST) {
// Run tests (except doc tests and without building examples)
cmd!(sh, "cargo test --workspace --lib --bins --tests --benches")
.run()
.expect("Please fix failing tests in output above.");
}
if what_to_run.contains(Check::DOC_TEST) {
// Run doc tests
cmd!(sh, "cargo test --workspace --doc")
.run()
.expect("Please fix failing doc-tests in output above.");
}
if what_to_run.contains(Check::DOC_CHECK) {
// Check that building docs work and does not emit warnings
std::env::set_var("RUSTDOCFLAGS", "-D warnings");
cmd!(
sh,
"cargo doc --workspace --all-features --no-deps --document-private-items"
)
.run()
.expect("Please fix doc warnings in output above.");
}
if what_to_run.contains(Check::BENCH_CHECK) {
let _subdir = sh.push_dir("benches");
// Check that benches are building
cmd!(sh, "cargo check --benches --target-dir ../target")
.run()
.expect("Failed to check the benches.");
}
if what_to_run.contains(Check::EXAMPLE_CHECK) {
// Build examples and check they compile
cmd!(sh, "cargo check --workspace --examples")
.run()
.expect("Please fix compiler errors for examples in output above.");
}
if what_to_run.contains(Check::COMPILE_CHECK) {
// Build bevy and check that it compiles
cmd!(sh, "cargo check --workspace")
.run()
.expect("Please fix compiler errors in output above.");
}
}