d3e44325b4
15 Commits
Author | SHA1 | Message | Date | |
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ccb9d0500f
|
bevy_reflect: Recursive registration (#5781)
# Objective Resolves #4154 Currently, registration must all be done manually: ```rust #[derive(Reflect)] struct Foo(Bar); #[derive(Reflect)] struct Bar(Baz); #[derive(Reflect)] struct Baz(usize); fn main() { // ... app .register_type::<Foo>() .register_type::<Bar>() .register_type::<Baz>() // .register_type::<usize>() <- This one is handled by Bevy, thankfully // ... } ``` This can grow really quickly and become very annoying to add, remove, and update as types change. It would be great if we could help reduce the number of types that a user must manually implement themselves. ## Solution As suggested in #4154, this PR adds automatic recursive registration. Essentially, when a type is registered, it may now also choose to register additional types along with it using the new `GetTypeRegistration::register_type_dependencies` trait method. The `Reflect` derive macro now automatically does this for all fields in structs, tuple structs, struct variants, and tuple variants. This is also done for tuples, arrays, `Vec<T>`, `HashMap<K, V>`, and `Option<T>`. This allows us to simplify the code above like: ```rust #[derive(Reflect)] struct Foo(Bar); #[derive(Reflect)] struct Bar(Baz); #[derive(Reflect)] struct Baz(usize); fn main() { // ... app.register_type::<Foo>() // ... } ``` This automatic registration only occurs if the type has not yet been registered. If it has been registered, we simply skip it and move to the next one. This reduces the cost of registration and prevents overwriting customized registrations. ## Considerations While this does improve ergonomics on one front, it's important to look at some of the arguments against adopting a PR like this. #### Generic Bounds ~~Since we need to be able to register the fields individually, we need those fields to implement `GetTypeRegistration`. This forces users to then add this trait as a bound on their generic arguments. This annoyance could be relieved with something like #5772.~~ This is no longer a major issue as the `Reflect` derive now adds the `GetTypeRegistration` bound by default. This should technically be okay, since we already add the `Reflect` bound. However, this can also be considered a breaking change for manual implementations that left out a `GetTypeRegistration` impl ~~or for items that contain dynamic types (e.g. `DynamicStruct`) since those also do not implement `GetTypeRegistration`~~. #### Registration Assumptions By automatically registering fields, users might inadvertently be relying on certain types to be automatically registered. If `Foo` auto-registers `Bar`, but `Foo` is later removed from the code, then anywhere that previously used or relied on `Bar`'s registration would now fail. --- ## Changelog - Added recursive type registration to structs, tuple structs, struct variants, tuple variants, tuples, arrays, `Vec<T>`, `HashMap<K, V>`, and `Option<T>` - Added a new trait in the hidden `bevy_reflect::__macro_exports` module called `RegisterForReflection` - Added `GetTypeRegistration` impl for `bevy_render::render_asset::RenderAssetUsages` ## Migration Guide All types that derive `Reflect` will now automatically add `GetTypeRegistration` as a bound on all (unignored) fields. This means that all reflected fields will need to also implement `GetTypeRegistration`. If all fields **derive** `Reflect` or are implemented in `bevy_reflect`, this should not cause any issues. However, manual implementations of `Reflect` that excluded a `GetTypeRegistration` impl for their type will need to add one. ```rust #[derive(Reflect)] struct Foo<T: FromReflect> { data: MyCustomType<T> } // OLD impl<T: FromReflect> Reflect for MyCustomType<T> {/* ... */} // NEW impl<T: FromReflect + GetTypeRegistration> Reflect for MyCustomType<T> {/* ... */} impl<T: FromReflect + GetTypeRegistration> GetTypeRegistration for MyCustomType<T> {/* ... */} ``` --------- Co-authored-by: James Liu <contact@jamessliu.com> Co-authored-by: radiish <cb.setho@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
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9e30aa7c92
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bevy_reflect_derive: Clean up attribute logic (#11777)
# Objective The code in `bevy_reflect_derive` could use some cleanup. ## Solution Took some of the changes in #11659 to create a dedicated PR for cleaning up the field and container attribute logic. #### Updated Naming I renamed `ReflectTraits` and `ReflectFieldAttr` to `ContainerAttributes` and `FieldAttributes`, respectively. I think these are clearer. #### Updated Parsing ##### Readability The parsing logic wasn't too bad before, but it was getting difficult to read. There was some duplicated logic between `Meta::List` and `Meta::Path` attributes. Additionally, all the logic was kept inside a large method. To simply things, I replaced the nested meta parsing with `ParseStream` parsing. In my opinion, this is easier to follow since it breaks up the large match statement into a small set of single-line if statements, where each if-block contains a single call to the appropriate attribute parsing method. ##### Flexibility On top of the added simplicity, this also makes our attribute parsing much more flexible. It allows us to more elegantly handle custom where clauses (i.e. `#[reflect(where T: Foo)]`) and it opens the door for more non-standard attribute syntax (e.g. #11659). ##### Errors This also allows us to automatically provide certain errors when parsing. For example, since we can use `stream.lookahead1()`, we get errors like the following for free: ``` error: expected one of: `ignore`, `skip_serializing`, `default` --> crates/bevy_reflect/src/lib.rs:1988:23 | 1988 | #[reflect(foo)] | ^^^ ``` --- ## Changelog > [!note] > All changes are internal to `bevy_reflect_derive` and should not affect the public API[^1]. - Renamed `ReflectTraits` to `ContainerAttributes` - Renamed `ReflectMeta::traits` to `ReflectMeta::attrs` - Renamed `ReflectFieldAttr` to `FieldAttributes` - Updated parsing logic for field/container attribute parsing - Now uses a `ParseStream` directly instead of nested meta parsing - General code cleanup of the field/container attribute modules for `bevy_reflect_derive` [^1]: Does not include errors, which may look slightly different. --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> |
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6e959db134
|
bevy_reflect: Type parameter bounds (#9046)
# Objective
Fixes #8965.
#### Background
For convenience and to ensure everything is setup properly, we
automatically add certain bounds to the derived types. The current
implementation does this by taking the types from all active fields and
adding them to the where-clause of the generated impls. I believe this
method was chosen because it won't add bounds to types that are
otherwise ignored.
```rust
#[derive(Reflect)]
struct Foo<T, U: SomeTrait, V> {
t: T,
u: U::Assoc,
#[reflect(ignore)]
v: [V; 2]
}
// Generates something like:
impl<T, U: SomeTrait, V> for Foo<T, U, V>
where
// Active:
T: Reflect,
U::Assoc: Reflect,
// Ignored:
[V; 2]: Send + Sync + Any
{
// ...
}
```
The self-referential type fails because it ends up using _itself_ as a
type bound due to being one of its own active fields.
```rust
#[derive(Reflect)]
struct Foo {
foo: Vec<Foo>
}
// Foo where Vec<Foo>: Reflect -> Vec<T> where T: Reflect -> Foo where Vec<Foo>: Reflect -> ...
```
## Solution
We can't simply parse all field types for the name of our type. That
would be both complex and prone to errors and false-positives. And even
if it wasn't, what would we replace the bound with?
Instead, I opted to go for a solution that only adds the bounds to what
really needs it: the type parameters. While the bounds on concrete types
make errors a bit cleaner, they aren't strictly necessary. This means we
can change our generated where-clause to only add bounds to generic type
parameters.
Doing this, though, returns us back to the problem of over-bounding
parameters that don't need to be bounded. To solve this, I added a new
container attribute (based on
[this](https://github.com/dtolnay/syn/issues/422#issuecomment-406882925)
comment and @nicopap's
[comment](https://github.com/bevyengine/bevy/pull/9046#issuecomment-1623593780))
that allows us to pass in a custom where clause to modify what bounds
are added to these type parameters.
This allows us to do stuff like:
```rust
trait Trait {
type Assoc;
}
// We don't need `T` to be reflectable since we only care about `T::Assoc`.
#[derive(Reflect)]
#[reflect(where T::Assoc: FromReflect)]
struct Foo<T: Trait>(T::Assoc);
#[derive(TypePath)]
struct Bar;
impl Trait for Bar {
type Assoc = usize;
}
#[derive(Reflect)]
struct Baz {
a: Foo<Bar>,
}
```
> **Note**
> I also
[tried](
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2ebf5a303e
|
Remove TypeUuid (#11497)
# Objective TypeUuid is deprecated, remove it. ## Migration Guide Convert any uses of `#[derive(TypeUuid)]` with `#[derive(TypePath]` for more complex uses see the relevant [documentation](https://docs.rs/bevy/latest/bevy/prelude/trait.TypePath.html) for more information. --------- Co-authored-by: ebola <dev@axiomatic> |
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daa8bf20df
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Fix nested generics in Reflect derive (#10791)
# Objective > Issue raised on [Discord](https://discord.com/channels/691052431525675048/1002362493634629796/1179182488787103776) Currently the following code fails due to a missing `TypePath` bound: ```rust #[derive(Reflect)] struct Foo<T>(T); #[derive(Reflect)] struct Bar<T>(Foo<T>); #[derive(Reflect)] struct Baz<T>(Bar<Foo<T>>); ``` ## Solution Add `TypePath` to the per-field bounds instead of _just_ the generic type parameter bounds. ### Related Work It should be noted that #9046 would help make these kinds of issues easier to work around and/or avoid entirely. --- ## Changelog - Fixes missing `TypePath` requirement when deriving `Reflect` on nested generics |
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44c769f7b9
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Improve TypeUuid's derive macro error messages (#9315)
# Objective - Better error message - More idiomatic code ## Solution Refactorize `TypeUuid` macros to use `syn::Result` instead of panic. ## Before/After error messages ### Missing `#[uuid]` attribtue #### Before ``` error: proc-macro derive panicked --> src\main.rs:1:10 | 1 | #[derive(TypeUuid)] | ^^^^^^^^ | = help: message: No `#[uuid = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"` attribute found. ``` #### After ``` error: No `#[uuid = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"]` attribute found. --> src\main.rs:3:10 | 3 | #[derive(TypeUuid)] | ^^^^^^^^ | = note: this error originates in the derive macro `TypeUuid` (in Nightly builds, run with -Z macro-backtrace for more info) ``` ### Malformed attribute #### Before ``` error: proc-macro derive panicked --> src\main.rs:3:10 | 3 | #[derive(TypeUuid)] | ^^^^^^^^ | = help: message: `uuid` attribute must take the form `#[uuid = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"`. ``` #### After ``` error: `uuid` attribute must take the form `#[uuid = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"]`. --> src\main.rs:4:1 | 4 | #[uuid = 42] | ^^^^^^^^^^^^ ``` ### UUID parse fail #### Before ``` error: proc-macro derive panicked --> src\main.rs:3:10 | 3 | #[derive(TypeUuid)] | ^^^^^^^^ | = help: message: Value specified to `#[uuid]` attribute is not a valid UUID.: Error(SimpleLength { len: 3 }) ``` #### After ``` error: Invalid UUID: invalid length: expected length 32 for simple format, found 3 --> src\main.rs:4:10 | 4 | #[uuid = "000"] | ^^^^^ ``` ### With [Error Lens](https://marketplace.visualstudio.com/items?itemName=usernamehw.errorlens) #### Before  #### After  --- ## Changelog - `#[derive(TypeUuid)]` provide better error messages. |
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a788e31ad5
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Fix CI for Rust 1.72 (#9562)
# Objective [Rust 1.72.0](https://blog.rust-lang.org/2023/08/24/Rust-1.72.0.html) is now stable. # Notes - `let-else` formatting has arrived! - I chose to allow `explicit_iter_loop` due to https://github.com/rust-lang/rust-clippy/issues/11074. We didn't hit any of the false positives that prevent compilation, but fixing this did produce a lot of the "symbol soup" mentioned, e.g. `for image in &mut *image_events {`. Happy to undo this if there's consensus the other way. --------- Co-authored-by: François <mockersf@gmail.com> |
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30d897a8bf
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fix clippy::default_constructed_unit_structs and trybuild errors (#9144)
# Objective With Rust `1.71.0` ([released a few minutes ago](https://github.com/rust-lang/rust/releases/tag/1.71.0)), clippy introduced a new lint ([`default_constructed_unit_structs`](https://rust-lang.github.io/rust-clippy/master/index.html#/default_constructed_unit_structs)) wich prevent calling `default()` on unit structs (e.g. `PhantomData::default()`). ## Solution Apply the lint suggestion. --------- Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
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aeeb20ec4c
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bevy_reflect: FromReflect Ergonomics Implementation (#6056)
# Objective **This implementation is based on https://github.com/bevyengine/rfcs/pull/59.** --- Resolves #4597 Full details and motivation can be found in the RFC, but here's a brief summary. `FromReflect` is a very powerful and important trait within the reflection API. It allows Dynamic types (e.g., `DynamicList`, etc.) to be formed into Real ones (e.g., `Vec<i32>`, etc.). This mainly comes into play concerning deserialization, where the reflection deserializers both return a `Box<dyn Reflect>` that almost always contain one of these Dynamic representations of a Real type. To convert this to our Real type, we need to use `FromReflect`. It also sneaks up in other ways. For example, it's a required bound for `T` in `Vec<T>` so that `Vec<T>` as a whole can be made `FromReflect`. It's also required by all fields of an enum as it's used as part of the `Reflect::apply` implementation. So in other words, much like `GetTypeRegistration` and `Typed`, it is very much a core reflection trait. The problem is that it is not currently treated like a core trait and is not automatically derived alongside `Reflect`. This makes using it a bit cumbersome and easy to forget. ## Solution Automatically derive `FromReflect` when deriving `Reflect`. Users can then choose to opt-out if needed using the `#[reflect(from_reflect = false)]` attribute. ```rust #[derive(Reflect)] struct Foo; #[derive(Reflect)] #[reflect(from_reflect = false)] struct Bar; fn test<T: FromReflect>(value: T) {} test(Foo); // <-- OK test(Bar); // <-- Panic! Bar does not implement trait `FromReflect` ``` #### `ReflectFromReflect` This PR also automatically adds the `ReflectFromReflect` (introduced in #6245) registration to the derived `GetTypeRegistration` impl— if the type hasn't opted out of `FromReflect` of course. <details> <summary><h4>Improved Deserialization</h4></summary> > **Warning** > This section includes changes that have since been descoped from this PR. They will likely be implemented again in a followup PR. I am mainly leaving these details in for archival purposes, as well as for reference when implementing this logic again. And since we can do all the above, we might as well improve deserialization. We can now choose to deserialize into a Dynamic type or automatically convert it using `FromReflect` under the hood. `[Un]TypedReflectDeserializer::new` will now perform the conversion and return the `Box`'d Real type. `[Un]TypedReflectDeserializer::new_dynamic` will work like what we have now and simply return the `Box`'d Dynamic type. ```rust // Returns the Real type let reflect_deserializer = UntypedReflectDeserializer::new(®istry); let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?; let output: SomeStruct = reflect_deserializer.deserialize(&mut deserializer)?.take()?; // Returns the Dynamic type let reflect_deserializer = UntypedReflectDeserializer::new_dynamic(®istry); let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?; let output: DynamicStruct = reflect_deserializer.deserialize(&mut deserializer)?.take()?; ``` </details> --- ## Changelog * `FromReflect` is now automatically derived within the `Reflect` derive macro * This includes auto-registering `ReflectFromReflect` in the derived `GetTypeRegistration` impl * ~~Renamed `TypedReflectDeserializer::new` and `UntypedReflectDeserializer::new` to `TypedReflectDeserializer::new_dynamic` and `UntypedReflectDeserializer::new_dynamic`, respectively~~ **Descoped** * ~~Changed `TypedReflectDeserializer::new` and `UntypedReflectDeserializer::new` to automatically convert the deserialized output using `FromReflect`~~ **Descoped** ## Migration Guide * `FromReflect` is now automatically derived within the `Reflect` derive macro. Items with both derives will need to remove the `FromReflect` one. ```rust // OLD #[derive(Reflect, FromReflect)] struct Foo; // NEW #[derive(Reflect)] struct Foo; ``` If using a manual implementation of `FromReflect` and the `Reflect` derive, users will need to opt-out of the automatic implementation. ```rust // OLD #[derive(Reflect)] struct Foo; impl FromReflect for Foo {/* ... */} // NEW #[derive(Reflect)] #[reflect(from_reflect = false)] struct Foo; impl FromReflect for Foo {/* ... */} ``` <details> <summary><h4>Removed Migrations</h4></summary> > **Warning** > This section includes changes that have since been descoped from this PR. They will likely be implemented again in a followup PR. I am mainly leaving these details in for archival purposes, as well as for reference when implementing this logic again. * The reflect deserializers now perform a `FromReflect` conversion internally. The expected output of `TypedReflectDeserializer::new` and `UntypedReflectDeserializer::new` is no longer a Dynamic (e.g., `DynamicList`), but its Real counterpart (e.g., `Vec<i32>`). ```rust let reflect_deserializer = UntypedReflectDeserializer::new_dynamic(®istry); let mut deserializer = ron:🇩🇪:Deserializer::from_str(input)?; // OLD let output: DynamicStruct = reflect_deserializer.deserialize(&mut deserializer)?.take()?; // NEW let output: SomeStruct = reflect_deserializer.deserialize(&mut deserializer)?.take()?; ``` Alternatively, if this behavior isn't desired, use the `TypedReflectDeserializer::new_dynamic` and `UntypedReflectDeserializer::new_dynamic` methods instead: ```rust // OLD let reflect_deserializer = UntypedReflectDeserializer::new(®istry); // NEW let reflect_deserializer = UntypedReflectDeserializer::new_dynamic(®istry); ``` </details> --------- Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
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1efc762924
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reflect: stable type path v2 (#7184)
# Objective
- Introduce a stable alternative to
[`std::any::type_name`](https://doc.rust-lang.org/std/any/fn.type_name.html).
- Rewrite of #5805 with heavy inspiration in design.
- On the path to #5830.
- Part of solving #3327.
## Solution
- Add a `TypePath` trait for static stable type path/name information.
- Add a `TypePath` derive macro.
- Add a `impl_type_path` macro for implementing internal and foreign
types in `bevy_reflect`.
---
## Changelog
- Added `TypePath` trait.
- Added `DynamicTypePath` trait and `get_type_path` method to `Reflect`.
- Added a `TypePath` derive macro.
- Added a `bevy_reflect::impl_type_path` for implementing `TypePath` on
internal and foreign types in `bevy_reflect`.
- Changed `bevy_reflect::utility::(Non)GenericTypeInfoCell` to
`(Non)GenericTypedCell<T>` which allows us to be generic over both
`TypeInfo` and `TypePath`.
- `TypePath` is now a supertrait of `Asset`, `Material` and
`Material2d`.
- `impl_reflect_struct` needs a `#[type_path = "..."]` attribute to be
specified.
- `impl_reflect_value` needs to either specify path starting with a
double colon (`::core::option::Option`) or an `in my_crate::foo`
declaration.
- Added `bevy_reflect_derive::ReflectTypePath`.
- Most uses of `Ident` in `bevy_reflect_derive` changed to use
`ReflectTypePath`.
## Migration Guide
- Implementors of `Asset`, `Material` and `Material2d` now also need to
derive `TypePath`.
- Manual implementors of `Reflect` will need to implement the new
`get_type_path` method.
## Open Questions
- [x] ~This PR currently does not migrate any usages of
`std::any::type_name` to use `bevy_reflect::TypePath` to ease the review
process. Should it?~ Migration will be left to a follow-up PR.
- [ ] This PR adds a lot of `#[derive(TypePath)]` and `T: TypePath` to
satisfy new bounds, mostly when deriving `TypeUuid`. Should we make
`TypePath` a supertrait of `TypeUuid`? [Should we remove `TypeUuid` in
favour of
`TypePath`?](
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e900bd9e12
|
Fix 1.69 CI clippy lints (#8450)
- Fix CI by implementing changes recommended by clippy - It uncovered a bug in a `bevy_ecs` test. Nice! |
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5e5a305d43
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bevy_reflect: Fix trailing comma breaking derives (#8014)
# Objective Fixes #7989 Based on #7991 by @CoffeeVampir3 ## Solution There were three parts to this issue: 1. `extend_where_clause` did not account for the optionality of a where clause's trailing comma ```rust // OKAY struct Foo<T> where T: Asset, {/* ... */} // ERROR struct Foo<T> where T: Asset {/* ... */} ``` 2. `FromReflect` derive logic was not actively using `extend_where_clause` which led to some inconsistencies (enums weren't adding _any_ additional bounds even) 3. Using `extend_where_clause` in the `FromReflect` derive logic meant we had to optionally add `Default` bounds to ignored fields iff the entire item itself was not already `Default` (otherwise the definition for `Handle<T>` wouldn't compile since `HandleType` doesn't impl `Default` but `Handle<T>` itself does) --- ## Changelog - Fixed issue where a missing trailing comma could break the reflection derives |
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b7ac5d5121
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Update trybuild tests for Rust 1.68 (#8002) | ||
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cbb4c26cad |
Enable deriving Reflect on structs with generic types (#7364)
# Objective I recently had an issue, where I have a struct: ``` struct Property { inner: T } ``` that I use as a wrapper for internal purposes. I don't want to update my struct definition to ``` struct Property<T: Reflect>{ inner: T } ``` because I still want to be able to build `Property<T>` for types `T` that are not `Reflect`. (and also because I don't want to update my whole code base with `<T: Reflect>` bounds) I still wanted to have reflection on it (for `bevy_inspector_egui`), but adding `derive(Reflect)` fails with the error: `T cannot be sent between threads safely. T needs to implement Sync.` I believe that `bevy_reflect` should adopt the model of other derives in the case of generics, which is to add the `Reflect` implementation only if the generics also implement `Reflect`. (That is the behaviour of other macros such as `derive(Clone)` or `derive(Debug)`. It's also the current behavior of `derive(FromReflect)`. Basically doing something like: ``` impl<T> Reflect for Foo<T> where T: Reflect ``` ## Solution - I updated the derive macros for `Structs` and `TupleStructs` to add extra `where` bounds. - Every type that is reflected will need a `T: Reflect` bound - Ignored types will need a `T: 'static + Send + Sync` bound. Here's the reason. For cases like this: ``` #[derive(Reflect)] struct Foo<T, U>{ a: T #[reflect(ignore)] b: U } ``` I had to add the bound `'static + Send + Sync` to ignored generics like `U`. The reason is that we want `Foo<T, U>` to be `Reflect: 'static + Send + Sync`, so `Foo<T, U>` must be able to implement those auto-traits. `Foo<T, U>` will only implement those auto-traits if every generic type implements them, including ignored types. This means that the previously compile-fail case now compiles: ``` #[derive(Reflect)] struct Foo<'a> { #[reflect(ignore)] value: &'a str, } ``` But `Foo<'a>` will only be useable in the cases where `'a: 'static` and panic if we don't have `'a: 'static`, which is what we want (nice bonus from this PR ;) ) --- ## Changelog > This section is optional. If this was a trivial fix, or has no externally-visible impact, you can delete this section. ### Added Possibility to add `derive(Reflect)` to structs and enums that contain generic types, like so: ``` #[derive(Reflect)] struct Foo<T>{ a: T } ``` Reflection will only be available if the generic type T also implements `Reflect`. (previously, this would just return a compiler error) |
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f8a229b0c9 |
bevy_reflect: Add compile fail tests for bevy_reflect (#7041)
# Objective There isn't really a way to test that code using bevy_reflect compiles or doesn't compile for certain scenarios. This would be especially useful for macro-centric PRs like #6511 and #6042. ## Solution Using `bevy_ecs_compile_fail_tests` as reference, added the `bevy_reflect_compile_fail_tests` crate. Currently, this crate contains a very simple test case. This is so that we can get the basic foundation of this crate agreed upon and merged so that more tests can be added by other PRs. ### Open Questions - [x] Should this be added to CI? (Answer: Yes) --- ## Changelog - Added the `bevy_reflect_compile_fail_tests` crate for testing compilation errors |