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https://github.com/bevyengine/bevy
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47 commits
Author | SHA1 | Message | Date | |
---|---|---|---|---|
Gino Valente
|
d21c7a1911
|
bevy_reflect: Function Overloading (Generic & Variadic Functions) (#15074)
# Objective
Currently function reflection requires users to manually monomorphize
their generic functions. For example:
```rust
fn add<T: Add<Output=T>>(a: T, b: T) -> T {
a + b
}
// We have to specify the type of `T`:
let reflect_add = add::<i32>.into_function();
```
This PR doesn't aim to solve that problem—this is just a limitation in
Rust. However, it also means that reflected functions can only ever work
for a single monomorphization. If we wanted to support other types for
`T`, we'd have to create a separate function for each one:
```rust
let reflect_add_i32 = add::<i32>.into_function();
let reflect_add_u32 = add::<u32>.into_function();
let reflect_add_f32 = add::<f32>.into_function();
// ...
```
So in addition to requiring manual monomorphization, we also lose the
benefit of having a single function handle multiple argument types.
If a user wanted to create a small modding script that utilized function
reflection, they'd have to either:
- Store all sets of supported monomorphizations and require users to
call the correct one
- Write out some logic to find the correct function based on the given
arguments
While the first option would work, it wouldn't be very ergonomic. The
second option is better, but it adds additional complexity to the user's
logic—complexity that `bevy_reflect` could instead take on.
## Solution
Introduce [function
overloading](https://en.wikipedia.org/wiki/Function_overloading).
A `DynamicFunction` can now be overloaded with other `DynamicFunction`s.
We can rewrite the above code like so:
```rust
let reflect_add = add::<i32>
.into_function()
.with_overload(add::<u32>)
.with_overload(add::<f32>);
```
When invoked, the `DynamicFunction` will attempt to find a matching
overload for the given set of arguments.
And while I went into this PR only looking to improve generic function
reflection, I accidentally added support for variadic functions as well
(hence why I use the broader term "overload" over "generic").
```rust
// Supports 1 to 4 arguments
let multiply_all = (|a: i32| a)
.into_function()
.with_overload(|a: i32, b: i32| a * b)
.with_overload(|a: i32, b: i32, c: i32| a * b * c)
.with_overload(|a: i32, b: i32, c: i32, d: i32| a * b * c * d);
```
This is simply an added bonus to this particular implementation. ~~Full
variadic support (i.e. allowing for an indefinite number of arguments)
will be added in a later PR.~~ I actually decided to limit the maximum
number of arguments to 63 to supplement faster lookups, a reduced memory
footprint, and faster cloning.
### Alternatives & Rationale
I explored a few options for handling generic functions. This PR is the
one I feel the most confident in, but I feel I should mention the others
and why I ultimately didn't move forward with them.
#### Adding `GenericDynamicFunction`
**TL;DR:** Adding a distinct `GenericDynamicFunction` type unnecessarily
splits and complicates the API.
<details>
<summary>Details</summary>
My initial explorations involved a dedicated `GenericDynamicFunction` to
contain and handle the mappings.
This was initially started back when `DynamicFunction` was distinct from
`DynamicClosure`. My goal was to not prevent us from being able to
somehow make `DynamicFunction` implement `Copy`. But once we reverted
back to a single `DynamicFunction`, that became a non-issue.
But that aside, the real problem was that it created a split in the API.
If I'm using a third-party library that uses function reflection, I have
to know whether to request a `DynamicFunction` or a
`GenericDynamicFunction`. I might not even know ahead of time which one
I want. It might need to be determined at runtime.
And if I'm creating a library, I might want a type to contain both
`DynamicFunction` and `GenericDynamicFunction`. This might not be
possible if, for example, I need to store the function in a `HashMap`.
The other concern is with `IntoFunction`. Right now `DynamicFunction`
trivially implements `IntoFunction` since it can just return itself. But
what should `GenericDynamicFunction` do? It could return itself wrapped
into a `DynamicFunction`, but then the API for `DynamicFunction` would
have to account for this. So then what was the point of having a
separate `GenericDynamicFunction` anyways?
And even apart from `IntoFunction`, there's nothing stopping someone
from manually creating a generic `DynamicFunction` through lying about
its `FunctionInfo` and wrapping a `GenericDynamicFunction`.
That being said, this is probably the "best" alternative if we added a
`Function` trait and stored functions as `Box<dyn Function>`.
However, I'm not convinced we gain much from this. Sure, we could keep
the API for `DynamicFunction` the same, but consumers of `Function` will
need to account for `GenericDynamicFunction` regardless (e.g. handling
multiple `FunctionInfo`, a ranged argument count, etc.). And for all
cases, except where using `DynamicFunction` directly, you end up
treating them all like `GenericDynamicFunction`.
Right now, if we did go with `GenericDynamicFunction`, the only major
benefit we'd gain would be saving 24 bytes. If memory ever does become
an issue here, we could swap over. But I think for the time being it's
better for us to pursue a clearer mental model and end-user ergonomics
through unification.
</details>
##### Using the `FunctionRegistry`
**TL;DR:** Having overloads only exist in the `FunctionRegistry`
unnecessarily splits and complicates the API.
<details>
<summary>Details</summary>
Another idea was to store the overloads in the `FunctionRegistry`. Users
would then just call functions directly through the registry (i.e.
`registry.call("my_func", my_args)`).
I didn't go with this option because of how it specifically relies on
the functions being registered. You'd not only always need access to the
registry, but you'd need to ensure that the functions you want to call
are even registered.
It also means you can't just store a generic `DynamicFunction` on a
type. Instead, you'll need to store the function's name and use that to
look up the function in the registry—even if it's only ever used by that
type.
Doing so also removes all the benefits of `DynamicFunction`, such as the
ability to pass it to functions accepting `IntoFunction`, modify it if
needed, and so on.
Like `GenericDynamicFunction` this introduces a split in the ecosystem:
you either store `DynamicFunction`, store a string to look up the
function, or force `DynamicFunction` to wrap your generic function
anyways. Or worse yet: have `DynamicFunction` wrap the lookup function
using `FunctionRegistryArc`.
</details>
#### Generic `ArgInfo`
**TL;DR:** Allowing `ArgInfo` and `ReturnInfo` to store the generic
information introduces a footgun when interpreting `FunctionInfo`.
<details>
<summary>Details</summary>
Regardless of how we represent a generic function, one thing is clear:
we need to be able to represent the information for such a function.
This PR does so by introducing a `FunctionInfoType` enum to wrap one or
more `FunctionInfo` values.
Originally, I didn't do this. I had `ArgInfo` and `ReturnInfo` allow for
generic types. This allowed us to have a single `FunctionInfo` to
represent our function, but then I realized that it actually lies about
our function.
If we have two `ArgInfo` that both allow for either `i32` or `u32`, what
does this tell us about our function? It turns out: nothing! We can't
know whether our function takes `(i32, i32)`, `(u32, u32)`, `(i32,
u32)`, or `(u32, i32)`.
It therefore makes more sense to just represent a function with multiple
`FunctionInfo` since that's really what it's made up of.
</details>
#### Flatten `FunctionInfo`
**TL;DR:** Flattening removes additional per-overload information some
users may desire and prevents us from adding more information in the
future.
<details>
<summary>Details</summary>
Why don't we just flatten multiple `FunctionInfo` into just one that can
contain multiple signatures?
This is something we could do, but I decided against it for a few
reasons:
- The only thing we'd be able to get rid of for each signature would be
the `name`. While not enough to not do it, it doesn't really suggest we
*have* to either.
- Some consumers may want access to the names of the functions that make
up the overloaded function. For example, to track a bug where an
undesirable function is being added as an overload. Or to more easily
locate the original function of an overload.
- We may eventually allow for more information to be stored on
`FunctionInfo`. For example, we may allow for documentation to be stored
like we do for `TypeInfo`. Consumers of this documentation may want
access to the documentation of each overload as they may provide
documentation specific to that overload.
</details>
## Testing
This PR adds lots of tests and benchmarks, and also adds to the example.
To run the tests:
```
cargo test --package bevy_reflect --all-features
```
To run the benchmarks:
```
cargo bench --bench reflect_function --all-features
```
To run the example:
```
cargo run --package bevy --example function_reflection --all-features
```
### Benchmarks
One of my goals with this PR was to leave the typical case of
non-overloaded functions largely unaffected by the changes introduced in
this PR. ~~And while the static size of `DynamicFunction` has increased
by 17% (from 136 to 160 bytes), the performance has generally stayed the
same~~ The static size of `DynamicFunction` has decreased from 136 to
112 bytes, while calling performance has generally stayed the same:
| | `main` | 7d293ab |
|
||
VitalyR
|
80e5d27e17
|
Fix a tiny mismatch between code and comment (#16021)
# Objective Fix a tiny mismatch between code and comment |
||
Clar Fon
|
efda7f3f9c
|
Simpler lint fixes: makes ci lints work but disables a lint for now (#15376)
Takes the first two commits from #15375 and adds suggestions from this comment: https://github.com/bevyengine/bevy/pull/15375#issuecomment-2366968300 See #15375 for more reasoning/motivation. ## Rebasing (rerunning) ```rust git switch simpler-lint-fixes git reset --hard main cargo fmt --all -- --unstable-features --config normalize_comments=true,imports_granularity=Crate cargo fmt --all git add --update git commit --message "rustfmt" cargo clippy --workspace --all-targets --all-features --fix cargo fmt --all -- --unstable-features --config normalize_comments=true,imports_granularity=Crate cargo fmt --all git add --update git commit --message "clippy" git cherry-pick e6c0b94f6795222310fb812fa5c4512661fc7887 ``` |
||
Gino Valente
|
83356b12c9
|
bevy_reflect: Replace "value" terminology with "opaque" (#15240)
# Objective Currently, the term "value" in the context of reflection is a bit overloaded. For one, it can be used synonymously with "data" or "variable". An example sentence would be "this function takes a reflected value". However, it is also used to refer to reflected types which are `ReflectKind::Value`. These types are usually either primitives, opaque types, or types that don't fall into any other `ReflectKind` (or perhaps could, but don't due to some limitation/difficulty). An example sentence would be "this function takes a reflected value type". This makes it difficult to write good documentation or other learning material without causing some amount of confusion to readers. Ideally, we'd be able to move away from the `ReflectKind::Value` usage and come up with a better term. ## Solution This PR replaces the terminology of "value" with "opaque" across `bevy_reflect`. This includes in documentation, type names, variant names, and macros. The term "opaque" was chosen because that's essentially how the type is treated within the reflection API. In other words, its internal structure is hidden. All we can do is work with the type itself. ### Primitives While primitives are not technically opaque types, I think it's still clearer to refer to them as "opaque" rather than keep the confusing "value" terminology. We could consider adding another concept for primitives (e.g. `ReflectKind::Primitive`), but I'm not sure that provides a lot of benefit right now. In most circumstances, they'll be treated just like an opaque type. They would also likely use the same macro (or two copies of the same macro but with different names). ## Testing You can test locally by running: ``` cargo test --package bevy_reflect --all-features ``` --- ## Migration Guide The reflection concept of "value type" has been replaced with a clearer "opaque type". The following renames have been made to account for this: - `ReflectKind::Value` → `ReflectKind::Opaque` - `ReflectRef::Value` → `ReflectRef::Opaque` - `ReflectMut::Value` → `ReflectMut::Opaque` - `ReflectOwned::Value` → `ReflectOwned::Opaque` - `TypeInfo::Value` → `TypeInfo::Opaque` - `ValueInfo` → `OpaqueInfo` - `impl_reflect_value!` → `impl_reflect_opaque!` - `impl_from_reflect_value!` → `impl_from_reflect_opaque!` Additionally, declaring your own opaque types no longer uses `#[reflect_value]`. This attribute has been replaced by `#[reflect(opaque)]`: ```rust // BEFORE #[derive(Reflect)] #[reflect_value(Default)] struct MyOpaqueType(u32); // AFTER #[derive(Reflect)] #[reflect(opaque)] #[reflect(Default)] struct MyOpaqueType(u32); ``` Note that the order in which `#[reflect(opaque)]` appears does not matter. |
||
Gino Valente
|
6e95f297ea
|
bevy_reflect: Automatic arg count validation (#15145)
# Objective Functions created into `DynamicFunction[Mut]` do not currently validate the number of arguments they are given before calling the function. I originally did this because I felt users would want to validate this themselves in the function rather than have it be done behind-the-scenes. I'm now realizing, however, that we could remove this boilerplate and if users wanted to check again then they would still be free to do so (it'd be more of a sanity check at that point). ## Solution Automatically validate the number of arguments passed to `DynamicFunction::call` and `DynamicFunctionMut::call[_once]`. This is a pretty trivial change since we just need to compare the length of the `ArgList` to the length of the `[ArgInfo]` in the function's `FunctionInfo`. I also ran the benchmarks just in case and saw no regression by doing this. ## Testing You can test locally by running: ``` cargo test --package bevy_reflect --all-features ``` |
||
Gino Valente
|
4d0961cc8a
|
bevy_reflect: Add ReflectRef /ReflectMut /ReflectOwned convenience casting methods (#15235)
# Objective #13320 added convenience methods for casting a `TypeInfo` into its respective variant: ```rust let info: &TypeInfo = <Vec<i32> as Typed>::type_info(); // We know `info` contains a `ListInfo`, so we can simply cast it: let list_info: &ListInfo = info.as_list().unwrap(); ``` This is especially helpful when you have already verified a type is a certain kind via `ReflectRef`, `ReflectMut`, `ReflectOwned`, or `ReflectKind`. As mentioned in that PR, though, it would be useful to add similar convenience methods to those types as well. ## Solution Added convenience casting methods to `ReflectRef`, `ReflectMut`, and `ReflectOwned`. With these methods, I was able to reduce our nesting in certain places throughout the crate. Additionally, I took this opportunity to move these types (and `ReflectKind`) to their own module to help clean up the `reflect` module. ## Testing You can test locally by running: ``` cargo test --package bevy_reflect --all-features ``` --- ## Showcase Convenience methods for casting `ReflectRef`, `ReflectMut`, and `ReflectOwned` into their respective variants has been added! This allows you to write cleaner code if you already know the kind of your reflected data: ```rust // BEFORE let ReflectRef::List(list) = list.reflect_ref() else { panic!("expected list"); }; // AFTER let list = list.reflect_ref().as_list().unwrap(); ``` --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: Pablo Reinhardt <126117294+pablo-lua@users.noreply.github.com> |
||
Gino Valente
|
59c0521690
|
bevy_reflect: Add Function trait (#15205)
# Objective While #13152 added function reflection, it didn't really make functions reflectable. Instead, it made it so that they can be called with reflected arguments and return reflected data. But functions themselves cannot be reflected. In other words, we can't go from `DynamicFunction` to `dyn PartialReflect`. ## Solution Allow `DynamicFunction` to actually be reflected. This PR adds the `Function` reflection subtrait (and corresponding `ReflectRef`, `ReflectKind`, etc.). With this new trait, we're able to implement `PartialReflect` on `DynamicFunction`. ### Implementors `Function` is currently only implemented for `DynamicFunction<'static>`. This is because we can't implement it generically over all functions—even those that implement `IntoFunction`. What about `DynamicFunctionMut`? Well, this PR does **not** implement `Function` for `DynamicFunctionMut`. The reasons for this are a little complicated, but it boils down to mutability. `DynamicFunctionMut` requires `&mut self` to be invoked since it wraps a `FnMut`. However, we can't really model this well with `Function`. And if we make `DynamicFunctionMut` wrap its internal `FnMut` in a `Mutex` to allow for `&self` invocations, then we run into either concurrency issues or recursion issues (or, in the worst case, both). So for the time-being, we won't implement `Function` for `DynamicFunctionMut`. It will be better to evaluate it on its own. And we may even consider the possibility of removing it altogether if it adds too much complexity to the crate. ### Dynamic vs Concrete One of the issues with `DynamicFunction` is the fact that it's both a dynamic representation (like `DynamicStruct` or `DynamicList`) and the only way to represent a function. Because of this, it's in a weird middle ground where we can't easily implement full-on `Reflect`. That would require `Typed`, but what static `TypeInfo` could it provide? Just that it's a `DynamicFunction`? None of the other dynamic types implement `Typed`. However, by not implementing `Reflect`, we lose the ability to downcast back to our `DynamicStruct`. Our only option is to call `Function::clone_dynamic`, which clones the data rather than by simply downcasting. This works in favor of the `PartialReflect::try_apply` implementation since it would have to clone anyways, but is definitely not ideal. This is also the reason I had to add `Debug` as a supertrait on `Function`. For now, this PR chooses not to implement `Reflect` for `DynamicFunction`. We may want to explore this in a followup PR (or even this one if people feel strongly that it's strictly required). The same is true for `FromReflect`. We may decide to add an implementation there as well, but it's likely out-of-scope of this PR. ## Testing You can test locally by running: ``` cargo test --package bevy_reflect --all-features ``` --- ## Showcase You can now pass around a `DynamicFunction` as a `dyn PartialReflect`! This also means you can use it as a field on a reflected type without having to ignore it (though you do need to opt out of `FromReflect`). ```rust #[derive(Reflect)] #[reflect(from_reflect = false)] struct ClickEvent { callback: DynamicFunction<'static>, } let event: Box<dyn Struct> = Box::new(ClickEvent { callback: (|| println!("Clicked!")).into_function(), }); // We can access our `DynamicFunction` as a `dyn PartialReflect` let callback: &dyn PartialReflect = event.field("callback").unwrap(); // And access function-related methods via the new `Function` trait let ReflectRef::Function(callback) = callback.reflect_ref() else { unreachable!() }; // Including calling the function callback.reflect_call(ArgList::new()).unwrap(); // Prints: Clicked! ``` |
||
Gino Valente
|
37443e0f3f
|
bevy_reflect: Add DynamicTyped trait (#15108)
# Objective Thanks to #7207, we now have a way to validate at the type-level that a reflected value is actually the type it says it is and not just a dynamic representation of that type. `dyn PartialReflect` values _might_ be a dynamic type, but `dyn Reflect` values are guaranteed to _not_ be a dynamic type. Therefore, we can start to add methods to `Reflect` that weren't really possible before. For example, we should now be able to always get a `&'static TypeInfo`, and not just an `Option<&'static TypeInfo>`. ## Solution Add the `DynamicTyped` trait. This trait is similar to `DynamicTypePath` in that it provides a way to use the non-object-safe `Typed` trait in an object-safe way. And since all types that derive `Reflect` will also derive `Typed`, we can safely add `DynamicTyped` as a supertrait of `Reflect`. This allows us to use it when just given a `dyn Reflect` trait object. ## Testing You can test locally by running: ``` cargo test --package bevy_reflect ``` --- ## Showcase `Reflect` now has a supertrait of `DynamicTyped`, allowing `TypeInfo` to be retrieved from a `dyn Reflect` trait object without having to unwrap anything! ```rust let value: Box<dyn Reflect> = Box::new(String::from("Hello!")); // BEFORE let info: &'static TypeInfo = value.get_represented_type_info().unwrap(); // AFTER let info: &'static TypeInfo = value.reflect_type_info(); ``` ## Migration Guide `Reflect` now has a supertrait of `DynamicTyped`. If you were manually implementing `Reflect` and did not implement `Typed`, you will now need to do so. |
||
Gino Valente
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2b4180ca8f
|
bevy_reflect: Function reflection terminology refactor (#14813)
# Objective One of the changes in #14704 made `DynamicFunction` effectively the same as `DynamicClosure<'static>`. This change meant that the de facto function type would likely be `DynamicClosure<'static>` instead of the intended `DynamicFunction`, since the former is much more flexible. We _could_ explore ways of making `DynamicFunction` implement `Copy` using some unsafe code, but it likely wouldn't be worth it. And users would likely still reach for the convenience of `DynamicClosure<'static>` over the copy-ability of `DynamicFunction`. The goal of this PR is to fix this confusion between the two types. ## Solution Firstly, the `DynamicFunction` type was removed. Again, it was no different than `DynamicClosure<'static>` so it wasn't a huge deal to remove. Secondly, `DynamicClosure<'env>` and `DynamicClosureMut<'env>` were renamed to `DynamicFunction<'env>` and `DynamicFunctionMut<'env>`, respectively. Yes, we still ultimately kept the naming of `DynamicFunction`, but changed its behavior to that of `DynamicClosure<'env>`. We need a term to refer to both functions and closures, and "function" was the best option. [Originally](https://discord.com/channels/691052431525675048/1002362493634629796/1274091992162242710), I was going to go with "callable" as the replacement term to encompass both functions and closures (e.g. `DynamciCallable<'env>`). However, it was [suggested](https://discord.com/channels/691052431525675048/1002362493634629796/1274653581777047625) by @SkiFire13 that the simpler "function" term could be used instead. While "callable" is perhaps the better umbrella term—being truly ambiguous over functions and closures— "function" is more familiar, used more often, easier to discover, and is subjectively just "better-sounding". ## Testing Most changes are purely swapping type names or updating documentation, but you can verify everything still works by running the following command: ``` cargo test --package bevy_reflect ``` |
||
radiish
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6ab8767d3b
|
reflect: implement the unique reflect rfc (#7207)
# Objective
- Implements the [Unique Reflect
RFC](https://github.com/nicopap/rfcs/blob/bevy-reflect-api/rfcs/56-better-reflect.md).
## Solution
- Implements the RFC.
- This implementation differs in some ways from the RFC:
- In the RFC, it was suggested `Reflect: Any` but `PartialReflect:
?Any`. During initial implementation I tried this, but we assume the
`PartialReflect: 'static` in a lot of places and the changes required
crept out of the scope of this PR.
- `PartialReflect::try_into_reflect` originally returned `Option<Box<dyn
Reflect>>` but i changed this to `Result<Box<dyn Reflect>, Box<dyn
PartialReflect>>` since the method takes by value and otherwise there
would be no way to recover the type. `as_full` and `as_full_mut` both
still return `Option<&(mut) dyn Reflect>`.
---
## Changelog
- Added `PartialReflect`.
- `Reflect` is now a subtrait of `PartialReflect`.
- Moved most methods on `Reflect` to the new `PartialReflect`.
- Added `PartialReflect::{as_partial_reflect, as_partial_reflect_mut,
into_partial_reflect}`.
- Added `PartialReflect::{try_as_reflect, try_as_reflect_mut,
try_into_reflect}`.
- Added `<dyn PartialReflect>::{try_downcast_ref, try_downcast_mut,
try_downcast, try_take}` supplementing the methods on `dyn Reflect`.
## Migration Guide
- Most instances of `dyn Reflect` should be changed to `dyn
PartialReflect` which is less restrictive, however trait bounds should
generally stay as `T: Reflect`.
- The new `PartialReflect::{as_partial_reflect, as_partial_reflect_mut,
into_partial_reflect, try_as_reflect, try_as_reflect_mut,
try_into_reflect}` methods as well as `Reflect::{as_reflect,
as_reflect_mut, into_reflect}` will need to be implemented for manual
implementors of `Reflect`.
## Future Work
- This PR is designed to be followed up by another "Unique Reflect Phase
2" that addresses the following points:
- Investigate making serialization revolve around `Reflect` instead of
`PartialReflect`.
- [Remove the `try_*` methods on `dyn PartialReflect` since they are
stop
gaps](https://github.com/bevyengine/bevy/pull/7207#discussion_r1083476050).
- Investigate usages like `ReflectComponent`. In the places they
currently use `PartialReflect`, should they be changed to use `Reflect`?
- Merging this opens the door to lots of reflection features we haven't
been able to implement.
- We could re-add [the `Reflectable`
trait](
|
||
Gino Valente
|
297c0a3954
|
bevy_reflect: Add DynamicSet to dynamic_types example (#14665)
# Objective The `dynamic_types` example was missing a reference to the newly added `DynamicSet` type. ## Solution Add `DynamicSet` to the `dynamic_types` example. For parity with the other dynamic types, I also implemented `FromIterator<T: Reflect>`, `FromIterator<Box<dyn Reflect>>`, and `IntoIterator for &DynamicSet`. ## Testing You can run the example locally: ``` cargo run --example dynamic_types ``` |
||
Gino Valente
|
a0cc636ea3
|
bevy_reflect: Anonymous function parsing (#14641)
# Objective ### TL;DR #14098 added the `FunctionRegistry` but had some last minute complications due to anonymous functions. It ended up going with a "required name" approach to ensure anonymous functions would always have a name. However, this approach isn't ideal for named functions since, by definition, they will always have a name. Therefore, this PR aims to modify function reflection such that we can make function registration easier for named functions, while still allowing anonymous functions to be registered as well. ### Context Function registration (#14098) ran into a little problem: anonymous functions. Anonymous functions, including function pointers, have very non-unique type names. For example, the anonymous function `|a: i32, b: i32| a + b` has the type name of `fn(i32, i32) -> i32`. This obviously means we'd conflict with another function like `|a: i32, b: i32| a - b`. The solution that #14098 landed on was to always require a name during function registration. The downside with this is that named functions (e.g. `fn add(a: i32, b: i32) -> i32 { a + b }`) had to redundantly provide a name. Additionally, manually constructed `DynamicFunction`s also ran into this ergonomics issue. I don't entirely know how the function registry will be used, but I have a strong suspicion that most of its registrations will either be named functions or manually constructed `DynamicFunction`s, with anonymous functions only being used here and there for quick prototyping or adding small functionality. Why then should the API prioritize the anonymous function use case by always requiring a name during registration? #### Telling Functions Apart Rust doesn't provide a lot of out-of-the-box tools for reflecting functions. One of the biggest hurdles in attempting to solve the problem outlined above would be to somehow tell the different kinds of functions apart. Let's briefly recap on the categories of functions in Rust: | Category | Example | | ------------------ | ----------------------------------------- | | Named function | `fn add(a: i32, b: i32) -> i32 { a + b }` | | Closure | `\|a: i32\| a + captured_variable` | | Anonymous function | `\|a: i32, b: i32\| a + b` | | Function pointer | `fn(i32, i32) -> i32` | My first thought was to try and differentiate these categories based on their size. However, we can see that this doesn't quite work: | Category | `size_of` | | ------------------ | --------- | | Named function | 0 | | Closure | 0+ | | Anonymous function | 0 | | Function pointer | 8 | Not only does this not tell anonymous functions from named ones, but it struggles with pretty much all of them. My second then was to differentiate based on type name: | Category | `type_name` | | ------------------ | ----------------------- | | Named function | `foo::bar::baz` | | Closure | `foo::bar::{{closure}}` | | Anonymous function | `fn() -> String` | | Function pointer | `fn() -> String` | This is much better. While it can't distinguish between function pointers and anonymous functions, this doesn't matter too much since we only care about whether we can _name_ the function. So why didn't we implement this in #14098? #### Relying on `type_name` While this solution was known about while working on #14098, it was left out from that PR due to it being potentially controversial. The [docs](https://doc.rust-lang.org/stable/std/any/fn.type_name.html) for `std::any::type_name` state: > The returned string must not be considered to be a unique identifier of a type as multiple types may map to the same type name. Similarly, there is no guarantee that all parts of a type will appear in the returned string: for example, lifetime specifiers are currently not included. In addition, the output may change between versions of the compiler. So that's it then? We can't use `type_name`? Well, this statement isn't so much a rule as it is a guideline. And Bevy is no stranger to bending the rules to make things work or to improve ergonomics. Remember that before `TypePath`, Bevy's scene system was entirely dependent on `type_name`. Not to mention that `type_name` is being used as a key into both the `TypeRegistry` and the `FunctionRegistry`. Bevy's practices aside, can we reliably use `type_name` for this? My answer would be "yes". Anonymous functions are anonymous. They have no name. There's nothing Rust could do to give them a name apart from generating a random string of characters. But remember that this is a diagnostic tool, it doesn't make sense to obfuscate the type by randomizing the output. So changing it to be anything other than what it is now is very unlikely. The only changes that I could potentially see happening are: 1. Closures replace `{{closure}}` with the name of their variable 2. Lifetimes are included in the output I don't think the first is likely to happen, but if it does then it actually works out in our favor: closures are now named! The second point is probably the likeliest. However, adding lifetimes doesn't mean we can't still rely on `type_name` to determine whether or not a function is named. So we should be okay in this case as well. ## Solution Parse the `type_name` of the function in the `TypedFunction` impl to determine if the function is named or anonymous. This once again makes `FunctionInfo::name` optional. For manual constructions of `DynamicFunction`, `FunctionInfo::named` or ``FunctionInfo::anonymous` can be used. The `FunctionRegistry` API has also been reworked to account for this change. `FunctionRegistry::register` no longer takes a name and instead takes it from the supplied function, returning a `FunctionRegistrationError::MissingName` error if the name is `None`. This also doubles as a replacement for the old `FunctionRegistry::register_dynamic` method, which has been removed. To handle anonymous functions, a `FunctionRegistry::register_with_name` method has been added. This works in the same way `FunctionRegistry::register` used to work before this PR. The overwriting methods have been updated in a similar manner, with modifications to `FunctionRegistry::overwrite_registration`, the removal of `FunctionRegistry::overwrite_registration_dynamic`, and the addition of `FunctionRegistry::overwrite_registration_with_name`. This PR also updates the methods on `App` in a similar way: `App::register_function` no longer requires a name argument and `App::register_function_with_name` has been added to handle anonymous functions (and eventually closures). ## Testing You can run the tests locally by running: ``` cargo test --package bevy_reflect --features functions ``` --- ## Internal Migration Guide > [!important] > Function reflection was introduced as part of the 0.15 dev cycle. This migration guide was written for developers relying on `main` during this cycle, and is not a breaking change coming from 0.14. > [!note] > This list is not exhaustive. It only contains some of the most important changes. `FunctionRegistry::register` no longer requires a name string for named functions. Anonymous functions, however, need to be registered using `FunctionRegistry::register_with_name`. ```rust // BEFORE registry .register(std::any::type_name_of_val(&foo), foo)? .register("bar", || println!("Hello world!")); // AFTER registry .register(foo)? .register_with_name("bar", || println!("Hello world!")); ``` `FunctionInfo::name` is now optional. Anonymous functions and closures will now have their name set to `None` by default. Additionally, `FunctionInfo::new` has been renamed to `FunctionInfo::named`. |
||
Gino Valente
|
df61117850
|
bevy_reflect: Function registry (#14098)
# Objective #13152 added support for reflecting functions. Now, we need a way to register those functions such that they may be accessed anywhere within the ECS. ## Solution Added a `FunctionRegistry` type similar to `TypeRegistry`. This allows a function to be registered and retrieved by name. ```rust fn foo() -> i32 { 123 } let mut registry = FunctionRegistry::default(); registry.register("my_function", foo); let function = registry.get_mut("my_function").unwrap(); let value = function.call(ArgList::new()).unwrap().unwrap_owned(); assert_eq!(value.downcast_ref::<i32>(), Some(&123)); ``` Additionally, I added an `AppFunctionRegistry` resource which wraps a `FunctionRegistryArc`. Functions can be registered into this resource using `App::register_function` or by getting a mutable reference to the resource itself. ### Limitations #### `Send + Sync` In order to get this registry to work across threads, it needs to be `Send + Sync`. This means that `DynamicFunction` needs to be `Send + Sync`, which means that its internal function also needs to be `Send + Sync`. In most cases, this won't be an issue because standard Rust functions (the type most likely to be registered) are always `Send + Sync`. Additionally, closures tend to be `Send + Sync` as well, granted they don't capture any `!Send` or `!Sync` variables. This PR adds this `Send + Sync` requirement, but as mentioned above, it hopefully shouldn't be too big of an issue. #### Closures Unfortunately, closures can't be registered yet. This will likely be explored and added in a followup PR. ### Future Work Besides addressing the limitations listed above, another thing we could look into is improving the lookup of registered functions. One aspect is in the performance of hashing strings. The other is in the developer experience of having to call `std::any::type_name_of_val` to get the name of their function (assuming they didn't give it a custom name). ## Testing You can run the tests locally with: ``` cargo test --package bevy_reflect ``` --- ## Changelog - Added `FunctionRegistry` - Added `AppFunctionRegistry` (a `Resource` available from `bevy_ecs`) - Added `FunctionRegistryArc` - Added `FunctionRegistrationError` - Added `reflect_functions` feature to `bevy_ecs` and `bevy_app` - `FunctionInfo` is no longer `Default` - `DynamicFunction` now requires its wrapped function be `Send + Sync` ## Internal Migration Guide > [!important] > Function reflection was introduced as part of the 0.15 dev cycle. This migration guide was written for developers relying on `main` during this cycle, and is not a breaking change coming from 0.14. `DynamicFunction` (both those created manually and those created with `IntoFunction`), now require `Send + Sync`. All standard Rust functions should meet that requirement. Closures, on the other hand, may not if they capture any `!Send` or `!Sync` variables from its environment. |
||
Rich Churcher
|
924f1cbc02
|
Fix lints in nightly (#14543)
# Objective Similar to #14537 , this fixes a minor lint issue causing CI failures when using nightly toolchain. ## Solution Add `#[allow(dead_code)]` to unused sample code. ## Testing `cargo run -p ci -- lints` using 1.82 toolchain. |
||
Robert Walter
|
52a2a3b146
|
Dedicated Reflect implementation for Set -like things (#13014)
# Objective I just wanted to inspect `HashSet`s in `bevy-inspector-egui` but I noticed that it didn't work for some reason. A few minutes later I found myself looking into the bevy reflect impls noticing that `HashSet`s have been covered only rudimentary up until now. ## Solution I'm not sure if this is overkill (especially the first bullet), but here's a list of the changes: - created a whole new trait and enum variants for `ReflectRef` and the like called `Set` - mostly oriented myself at the `Map` trait and made the necessary changes until RA was happy - create macro `impl_reflect_for_hashset!` and call it on `std::HashSet` and `hashbrown::HashSet` Extra notes: - no `get_mut` or `get_mut_at` mirroring the `std::HashSet` - `insert[_boxed]` and `remove` return `bool` mirroring `std::HashSet`, additionally that bool is reflect as I thought that would be how we handle things in bevy reflect, but I'm not sure on this - ser/de are handled via `SeqAccess` - I'm not sure about the general deduplication property of this impl of `Set` that is generally expected? I'm also not sure yet if `Map` does provide this. This mainly refers to the `Dynamic[...]` structs - I'm not sure if there are other methods missing from the `trait`, I felt like `contains` or the set-operations (union/diff/...) could've been helpful, but I wanted to get out the bare minimum for feedback first --- ## Changelog ### Added - `Set` trait for `bevy_reflect` ### Changed - `std::collections::HashSet` and `bevy_utils::hashbrown::HashSet` now implement a more complete set of reflect functionalities instead of "just" `reflect_value` - `TypeInfo` contains a new variant `Set` that contains `SetInfo` - `ReflectKind` contains a new variant `Set` - `ReflectRef` contains a new variant `Set` - `ReflectMut` contains a new variant `Set` - `ReflectOwned` contains a new variant `Set` ## Migration Guide - The new `Set` variants on the enums listed in the change section should probably be considered by people working with this level of the lib ### Help wanted! I'm not sure if this change is able to break code. From my understanding it shouldn't since we just add functionality but I'm not sure yet if theres anything missing from my impl that would be normally provided by `impl_reflect_value!` |
||
Gino Valente
|
af865e76a3
|
bevy_reflect: Improve DynamicFunction ergonomics (#14201)
# Objective Many functions can be converted to `DynamicFunction` using `IntoFunction`. Unfortunately, we are limited by Rust itself and the implementations are far from exhaustive. For example, we can't convert functions with more than 16 arguments. Additionally, we can't handle returns with lifetimes not tied to the lifetime of the first argument. In such cases, users will have to create their `DynamicFunction` manually. Let's take the following function: ```rust fn get(index: usize, list: &Vec<String>) -> &String { &list[index] } ``` This function cannot be converted to a `DynamicFunction` via `IntoFunction` due to the lifetime of the return value being tied to the second argument. Therefore, we need to construct the `DynamicFunction` manually: ```rust DynamicFunction::new( |mut args, info| { let list = args .pop() .unwrap() .take_ref::<Vec<String>>(&info.args()[1])?; let index = args.pop().unwrap().take_owned::<usize>(&info.args()[0])?; Ok(Return::Ref(get(index, list))) }, FunctionInfo::new() .with_name("get") .with_args(vec![ ArgInfo:🆕:<usize>(0).with_name("index"), ArgInfo:🆕:<&Vec<String>>(1).with_name("list"), ]) .with_return_info(ReturnInfo:🆕:<&String>()), ); ``` While still a small and straightforward snippet, there's a decent amount going on here. There's a lot of room for improvements when it comes to ergonomics and readability. The goal of this PR is to address those issues. ## Solution Improve the ergonomics and readability of manually created `DynamicFunction`s. Some of the major changes: 1. Removed the need for `&ArgInfo` when reifying arguments (i.e. the `&info.args()[1]` calls) 2. Added additional `pop` methods on `ArgList` to handle both popping and casting 3. Added `take` methods on `ArgList` for taking the arguments out in order 4. Removed the need for `&FunctionInfo` in the internal closure (Change 1 made it no longer necessary) 5. Added methods to automatically handle generating `ArgInfo` and `ReturnInfo` With all these changes in place, we get something a lot nicer to both write and look at: ```rust DynamicFunction::new( |mut args| { let index = args.take::<usize>()?; let list = args.take::<&Vec<String>>()?; Ok(Return::Ref(get(index, list))) }, FunctionInfo::new() .with_name("get") .with_arg::<usize>("index") .with_arg::<&Vec<String>>("list") .with_return::<&String>(), ); ``` Alternatively, to rely on type inference for taking arguments, you could do: ```rust DynamicFunction::new( |mut args| { let index = args.take_owned()?; let list = args.take_ref()?; Ok(Return::Ref(get(index, list))) }, FunctionInfo::new() .with_name("get") .with_arg::<usize>("index") .with_arg::<&Vec<String>>("list") .with_return::<&String>(), ); ``` ## Testing You can test locally by running: ``` cargo test --package bevy_reflect ``` --- ## Changelog - Removed `&ArgInfo` argument from `FromArg::from_arg` trait method - Removed `&ArgInfo` argument from `Arg::take_***` methods - Added `ArgValue` - `Arg` is now a struct containing an `ArgValue` and an argument `index` - `Arg::take_***` methods now require `T` is also `TypePath` - Added `Arg::new`, `Arg::index`, `Arg::value`, `Arg::take_value`, and `Arg::take` methods - Replaced `ArgId` in `ArgError` with just the argument `index` - Added `ArgError::EmptyArgList` - Renamed `ArgList::push` to `ArgList::push_arg` - Added `ArgList::pop_arg`, `ArgList::pop_owned`, `ArgList::pop_ref`, and `ArgList::pop_mut` - Added `ArgList::take_arg`, `ArgList::take_owned`, `ArgList::take_ref`, `ArgList::take_mut`, and `ArgList::take` - `ArgList::pop` is now generic - Renamed `FunctionError::InvalidArgCount` to `FunctionError::ArgCountMismatch` - The closure given to `DynamicFunction::new` no longer has a `&FunctionInfo` argument - Added `FunctionInfo::with_arg` - Added `FunctionInfo::with_return` ## Internal Migration Guide > [!important] > Function reflection was introduced as part of the 0.15 dev cycle. This migration guide was written for developers relying on `main` during this cycle, and is not a breaking change coming from 0.14. * The `FromArg::from_arg` trait method and the `Arg::take_***` methods no longer take a `&ArgInfo` argument. * What used to be `Arg` is now `ArgValue`. `Arg` is now a struct which contains an `ArgValue`. * `Arg::take_***` methods now require `T` is also `TypePath` * Instances of `id: ArgId` in `ArgError` have been replaced with `index: usize` * `ArgList::push` is now `ArgList::push_arg`. It also takes the new `ArgValue` type. * `ArgList::pop` has become `ArgList::pop_arg` and now returns `ArgValue`. `Arg::pop` now takes a generic type and downcasts to that type. It's recommended to use `ArgList::take` and friends instead since they allow removing the arguments from the list in the order they were pushed (rather than reverse order). * `FunctionError::InvalidArgCount` is now `FunctionError::ArgCountMismatch` * The closure given to `DynamicFunction::new` no longer has a `&FunctionInfo` argument. This argument can be removed. |
||
Gino Valente
|
1042f09c2e
|
bevy_reflect: Add DynamicClosure and DynamicClosureMut (#14141)
# Objective As mentioned in [this](https://github.com/bevyengine/bevy/pull/13152#issuecomment-2198387297) comment, creating a function registry (see #14098) is a bit difficult due to the requirements of `DynamicFunction`. Internally, a `DynamicFunction` contains a `Box<dyn FnMut>` (the function that reifies reflected arguments and calls the actual function), which requires `&mut self` in order to be called. This means that users would require a mutable reference to the function registry for it to be useful— which isn't great. And they can't clone the `DynamicFunction` either because cloning an `FnMut` isn't really feasible (wrapping it in an `Arc` would allow it to be cloned but we wouldn't be able to call the clone since we need a mutable reference to the `FnMut`, which we can't get with multiple `Arc`s still alive, requiring us to also slap in a `Mutex`, which adds additional overhead). And we don't want to just replace the `dyn FnMut` with `dyn Fn` as that would prevent reflecting closures that mutate their environment. Instead, we need to introduce a new type to split the requirements of `DynamicFunction`. ## Solution Introduce new types for representing closures. Specifically, this PR introduces `DynamicClosure` and `DynamicClosureMut`. Similar to how `IntoFunction` exists for `DynamicFunction`, two new traits were introduced: `IntoClosure` and `IntoClosureMut`. Now `DynamicFunction` stores a `dyn Fn` with a `'static` lifetime. `DynamicClosure` also uses a `dyn Fn` but has a lifetime, `'env`, tied to its environment. `DynamicClosureMut` is most like the old `DynamicFunction`, keeping the `dyn FnMut` and also typing its lifetime, `'env`, to the environment Here are some comparison tables: | | `DynamicFunction` | `DynamicClosure` | `DynamicClosureMut` | | - | ----------------- | ---------------- | ------------------- | | Callable with `&self` | ✅ | ✅ | ❌ | | Callable with `&mut self` | ✅ | ✅ | ✅ | | Allows for non-`'static` lifetimes | ❌ | ✅ | ✅ | | | `IntoFunction` | `IntoClosure` | `IntoClosureMut` | | - | -------------- | ------------- | ---------------- | | Convert `fn` functions | ✅ | ✅ | ✅ | | Convert `fn` methods | ✅ | ✅ | ✅ | | Convert anonymous functions | ✅ | ✅ | ✅ | | Convert closures that capture immutable references | ❌ | ✅ | ✅ | | Convert closures that capture mutable references | ❌ | ❌ | ✅ | | Convert closures that capture owned values | ❌[^1] | ✅ | ✅ | [^1]: Due to limitations in Rust, `IntoFunction` can't be implemented for just functions (unless we forced users to manually coerce them to function pointers first). So closures that meet the trait requirements _can technically_ be converted into a `DynamicFunction` as well. To both future-proof and reduce confusion, though, we'll just pretend like this isn't a thing. ```rust let mut list: Vec<i32> = vec![1, 2, 3]; // `replace` is a closure that captures a mutable reference to `list` let mut replace = |index: usize, value: i32| -> i32 { let old_value = list[index]; list[index] = value; old_value }; // Convert the closure into a dynamic closure using `IntoClosureMut::into_closure_mut` let mut func: DynamicClosureMut = replace.into_closure_mut(); // Dynamically call the closure: let args = ArgList::default().push_owned(1_usize).push_owned(-2_i32); let value = func.call_once(args).unwrap().unwrap_owned(); // Check the result: assert_eq!(value.take::<i32>().unwrap(), 2); assert_eq!(list, vec![1, -2, 3]); ``` ### `ReflectFn`/`ReflectFnMut` To make extending the function reflection system easier (the blanket impls for `IntoFunction`, `IntoClosure`, and `IntoClosureMut` are all incredibly short), this PR generalizes callables with two new traits: `ReflectFn` and `ReflectFnMut`. These traits mimic `Fn` and `FnMut` but allow for being called via reflection. In fact, their blanket implementations are identical save for `ReflectFn` being implemented over `Fn` types and `ReflectFnMut` being implemented over `FnMut` types. And just as `Fn` is a subtrait of `FnMut`, `ReflectFn` is a subtrait of `ReflectFnMut`. So anywhere that expects a `ReflectFnMut` can also be given a `ReflectFn`. To reiterate, these traits aren't 100% necessary. They were added in purely for extensibility. If we decide to split things up differently or add new traits/types in the future, then those changes should be much simpler to implement. ### `TypedFunction` Because of the split into `ReflectFn` and `ReflectFnMut`, we needed a new way to access the function type information. This PR moves that concept over into `TypedFunction`. Much like `Typed`, this provides a way to access a function's `FunctionInfo`. By splitting this trait out, it helps to ensure the other traits are focused on a single responsibility. ### Internal Macros The original function PR (#13152) implemented `IntoFunction` using a macro which was passed into an `all_tuples!` macro invocation. Because we needed the same functionality for these new traits, this PR has copy+pasted that code for `ReflectFn`, `ReflectFnMut`, and `TypedFunction`— albeit with some differences between them. Originally, I was going to try and macro-ify the impls and where clauses such that we wouldn't have to straight up duplicate a lot of this logic. However, aside from being more complex in general, autocomplete just does not play nice with such heavily nested macros (tried in both RustRover and VSCode). And both of those problems told me that it just wasn't worth it: we need to ensure the crate is easily maintainable, even at the cost of duplicating code. So instead, I made sure to simplify the macro code by removing all fully-qualified syntax and cutting the where clauses down to the bare essentials, which helps to clean up a lot of the visual noise. I also tried my best to document the macro logic in certain areas (I may even add a bit more) to help with maintainability for future devs. ### Documentation Documentation for this module was a bit difficult for me. So many of these traits and types are very interconnected. And each trait/type has subtle differences that make documenting it in a single place, like at the module level, difficult to do cleanly. Describing the valid signatures is also challenging to do well. Hopefully what I have here is okay. I think I did an okay job, but let me know if there any thoughts on ways to improve it. We can also move such a task to a followup PR for more focused discussion. ## Testing You can test locally by running: ``` cargo test --package bevy_reflect ``` --- ## Changelog - Added `DynamicClosure` struct - Added `DynamicClosureMut` struct - Added `IntoClosure` trait - Added `IntoClosureMut` trait - Added `ReflectFn` trait - Added `ReflectFnMut` trait - Added `TypedFunction` trait - `IntoFunction` now only works for standard Rust functions - `IntoFunction` no longer takes a lifetime parameter - `DynamicFunction::call` now only requires `&self` - Removed `DynamicFunction::call_once` - Changed the `IntoReturn::into_return` signature to include a where clause ## Internal Migration Guide > [!important] > Function reflection was introduced as part of the 0.15 dev cycle. This migration guide was written for developers relying on `main` during this cycle, and is not a breaking change coming from 0.14. ### `IntoClosure` `IntoFunction` now only works for standard Rust functions. Calling `IntoFunction::into_function` on a closure that captures references to its environment (either mutable or immutable), will no longer compile. Instead, you will need to use either `IntoClosure::into_closure` to create a `DynamicClosure` or `IntoClosureMut::into_closure_mut` to create a `DynamicClosureMut`, depending on your needs: ```rust let punct = String::from("!"); let print = |value: String| { println!("{value}{punct}"); }; // BEFORE let func: DynamicFunction = print.into_function(); // AFTER let func: DynamicClosure = print.into_closure(); ``` ### `IntoFunction` lifetime Additionally, `IntoFunction` no longer takes a lifetime parameter as it always expects a `'static` lifetime. Usages will need to remove any lifetime parameters: ```rust // BEFORE fn execute<'env, F: IntoFunction<'env, Marker>, Marker>(f: F) {/* ... */} // AFTER fn execute<F: IntoFunction<Marker>, Marker>(f: F) {/* ... */} ``` ### `IntoReturn` `IntoReturn::into_return` now has a where clause. Any manual implementors will need to add this where clause to their implementation. |
||
SpecificProtagonist
|
ab255aefc6
|
Implement FromIterator/IntoIterator for dynamic types (#14250)
# Objective Implement FromIterator/IntoIterator for dynamic types where missing Note: - can't impl `IntoIterator` for `&Array` & co because of orphan rules - `into_iter().collect()` is a no-op for `Vec`s because of specialization --- ## Migration Guide - Change `DynamicArray::from_vec` to `DynamicArray::from_iter` |
||
Gino Valente
|
276815a9a0
|
examples: Add Type Data reflection example (#13903)
# Objective Type data is a **super** useful tool to know about when working with reflection. However, most users don't fully understand how it works or that you can use it for more than just object-safe traits. This is unfortunate because it can be surprisingly simple to manually create your own type data. We should have an example detailing how type works, how users can define their own, and how thy can be used. ## Solution Added a `type_data` example. This example goes through all the major points about type data: - Why we need them - How they can be defined - The two ways they can be registered - A list of common/important type data provided by Bevy I also thought it might be good to go over the `#[reflect_trait]` macro as part of this example since it has all the other context, including how to define type data in places where `#[reflect_trait]` won't work. Because of this, I removed the `trait_reflection` example. ## Testing You can run the example locally with the following command: ``` cargo run --example type_data ``` --- ## Changelog - Added the `type_data` example - Removed the `trait_reflection` example |
||
Gino Valente
|
276dd04001
|
bevy_reflect: Function reflection (#13152)
# Objective
We're able to reflect types sooooooo... why not functions?
The goal of this PR is to make functions callable within a dynamic
context, where type information is not readily available at compile
time.
For example, if we have a function:
```rust
fn add(left: i32, right: i32) -> i32 {
left + right
}
```
And two `Reflect` values we've already validated are `i32` types:
```rust
let left: Box<dyn Reflect> = Box::new(2_i32);
let right: Box<dyn Reflect> = Box::new(2_i32);
```
We should be able to call `add` with these values:
```rust
// ?????
let result: Box<dyn Reflect> = add.call_dynamic(left, right);
```
And ideally this wouldn't just work for functions, but methods and
closures too!
Right now, users have two options:
1. Manually parse the reflected data and call the function themselves
2. Rely on registered type data to handle the conversions for them
For a small function like `add`, this isn't too bad. But what about for
more complex functions? What about for many functions?
At worst, this process is error-prone. At best, it's simply tedious.
And this is assuming we know the function at compile time. What if we
want to accept a function dynamically and call it with our own
arguments?
It would be much nicer if `bevy_reflect` could alleviate some of the
problems here.
## Solution
Added function reflection!
This adds a `DynamicFunction` type to wrap a function dynamically. This
can be called with an `ArgList`, which is a dynamic list of
`Reflect`-containing `Arg` arguments. It returns a `FunctionResult`
which indicates whether or not the function call succeeded, returning a
`Reflect`-containing `Return` type if it did succeed.
Many functions can be converted into this `DynamicFunction` type thanks
to the `IntoFunction` trait.
Taking our previous `add` example, this might look something like
(explicit types added for readability):
```rust
fn add(left: i32, right: i32) -> i32 {
left + right
}
let mut function: DynamicFunction = add.into_function();
let args: ArgList = ArgList::new().push_owned(2_i32).push_owned(2_i32);
let result: Return = function.call(args).unwrap();
let value: Box<dyn Reflect> = result.unwrap_owned();
assert_eq!(value.take::<i32>().unwrap(), 4);
```
And it also works on closures:
```rust
let add = |left: i32, right: i32| left + right;
let mut function: DynamicFunction = add.into_function();
let args: ArgList = ArgList::new().push_owned(2_i32).push_owned(2_i32);
let result: Return = function.call(args).unwrap();
let value: Box<dyn Reflect> = result.unwrap_owned();
assert_eq!(value.take::<i32>().unwrap(), 4);
```
As well as methods:
```rust
#[derive(Reflect)]
struct Foo(i32);
impl Foo {
fn add(&mut self, value: i32) {
self.0 += value;
}
}
let mut foo = Foo(2);
let mut function: DynamicFunction = Foo::add.into_function();
let args: ArgList = ArgList::new().push_mut(&mut foo).push_owned(2_i32);
function.call(args).unwrap();
assert_eq!(foo.0, 4);
```
### Limitations
While this does cover many functions, it is far from a perfect system
and has quite a few limitations. Here are a few of the limitations when
using `IntoFunction`:
1. The lifetime of the return value is only tied to the lifetime of the
first argument (useful for methods). This means you can't have a
function like `(a: i32, b: &i32) -> &i32` without creating the
`DynamicFunction` manually.
2. Only 15 arguments are currently supported. If the first argument is a
(mutable) reference, this number increases to 16.
3. Manual implementations of `Reflect` will need to implement the new
`FromArg`, `GetOwnership`, and `IntoReturn` traits in order to be used
as arguments/return types.
And some limitations of `DynamicFunction` itself:
1. All arguments share the same lifetime, or rather, they will shrink to
the shortest lifetime.
2. Closures that capture their environment may need to have their
`DynamicFunction` dropped before accessing those variables again (there
is a `DynamicFunction::call_once` to make this a bit easier)
3. All arguments and return types must implement `Reflect`. While not a
big surprise coming from `bevy_reflect`, this implementation could
actually still work by swapping `Reflect` out with `Any`. Of course,
that makes working with the arguments and return values a bit harder.
4. Generic functions are not supported (unless they have been manually
monomorphized)
And general, reflection gotchas:
1. `&str` does not implement `Reflect`. Rather, `&'static str`
implements `Reflect` (the same is true for `&Path` and similar types).
This means that `&'static str` is considered an "owned" value for the
sake of generating arguments. Additionally, arguments and return types
containing `&str` will assume it's `&'static str`, which is almost never
the desired behavior. In these cases, the only solution (I believe) is
to use `&String` instead.
### Followup Work
This PR is the first of two PRs I intend to work on. The second PR will
aim to integrate this new function reflection system into the existing
reflection traits and `TypeInfo`. The goal would be to register and call
a reflected type's methods dynamically.
I chose not to do that in this PR since the diff is already quite large.
I also want the discussion for both PRs to be focused on their own
implementation.
Another followup I'd like to do is investigate allowing common container
types as a return type, such as `Option<&[mut] T>` and `Result<&[mut] T,
E>`. This would allow even more functions to opt into this system. I
chose to not include it in this one, though, for the same reasoning as
previously mentioned.
### Alternatives
One alternative I had considered was adding a macro to convert any
function into a reflection-based counterpart. The idea would be that a
struct that wraps the function would be created and users could specify
which arguments and return values should be `Reflect`. It could then be
called via a new `Function` trait.
I think that could still work, but it will be a fair bit more involved,
requiring some slightly more complex parsing. And it of course is a bit
more work for the user, since they need to create the type via macro
invocation.
It also makes registering these functions onto a type a bit more
complicated (depending on how it's implemented).
For now, I think this is a fairly simple, yet powerful solution that
provides the least amount of friction for users.
---
## Showcase
Bevy now adds support for storing and calling functions dynamically
using reflection!
```rust
// 1. Take a standard Rust function
fn add(left: i32, right: i32) -> i32 {
left + right
}
// 2. Convert it into a type-erased `DynamicFunction` using the `IntoFunction` trait
let mut function: DynamicFunction = add.into_function();
// 3. Define your arguments from reflected values
let args: ArgList = ArgList::new().push_owned(2_i32).push_owned(2_i32);
// 4. Call the function with your arguments
let result: Return = function.call(args).unwrap();
// 5. Extract the return value
let value: Box<dyn Reflect> = result.unwrap_owned();
assert_eq!(value.take::<i32>().unwrap(), 4);
```
## Changelog
#### TL;DR
- Added support for function reflection
- Added a new `Function Reflection` example:
|
||
Gino Valente
|
5db52663b3
|
bevy_reflect: Custom attributes (#11659)
# Objective As work on the editor starts to ramp up, it might be nice to start allowing types to specify custom attributes. These can be used to provide certain functionality to fields, such as ranges or controlling how data is displayed. A good example of this can be seen in [`bevy-inspector-egui`](https://github.com/jakobhellermann/bevy-inspector-egui) with its [`InspectorOptions`](https://docs.rs/bevy-inspector-egui/0.22.1/bevy_inspector_egui/struct.InspectorOptions.html): ```rust #[derive(Reflect, Default, InspectorOptions)] #[reflect(InspectorOptions)] struct Slider { #[inspector(min = 0.0, max = 1.0)] value: f32, } ``` Normally, as demonstrated in the example above, these attributes are handled by a derive macro and stored in a corresponding `TypeData` struct (i.e. `ReflectInspectorOptions`). Ideally, we would have a good way of defining this directly via reflection so that users don't need to create and manage a whole proc macro just to allow these sorts of attributes. And note that this doesn't have to just be for inspectors and editors. It can be used for things done purely on the code side of things. ## Solution Create a new method for storing attributes on fields via the `Reflect` derive. These custom attributes are stored in type info (e.g. `NamedField`, `StructInfo`, etc.). ```rust #[derive(Reflect)] struct Slider { #[reflect(@0.0..=1.0)] value: f64, } let TypeInfo::Struct(info) = Slider::type_info() else { panic!("expected struct info"); }; let field = info.field("value").unwrap(); let range = field.get_attribute::<RangeInclusive<f64>>().unwrap(); assert_eq!(*range, 0.0..=1.0); ``` ## TODO - [x] ~~Bikeshed syntax~~ Went with a type-based approach, prefixed by `@` for ease of parsing and flexibility - [x] Add support for custom struct/tuple struct field attributes - [x] Add support for custom enum variant field attributes - [x] ~~Add support for custom enum variant attributes (maybe?)~~ ~~Will require a larger refactor. Can be saved for a future PR if we really want it.~~ Actually, we apparently still have support for variant attributes despite not using them, so it was pretty easy to add lol. - [x] Add support for custom container attributes - [x] Allow custom attributes to store any reflectable value (not just `Lit`) - [x] ~~Store attributes in registry~~ This PR used to store these in attributes in the registry, however, it has since switched over to storing them in type info - [x] Add example ## Bikeshedding > [!note] > This section was made for the old method of handling custom attributes, which stored them by name (i.e. `some_attribute = 123`). The PR has shifted away from that, to a more type-safe approach. > > This section has been left for reference. There are a number of ways we can syntactically handle custom attributes. Feel free to leave a comment on your preferred one! Ideally we want one that is clear, readable, and concise since these will potentially see _a lot_ of use. Below is a small, non-exhaustive list of them. Note that the `skip_serializing` reflection attribute is added to demonstrate how each case plays with existing reflection attributes. <details> <summary>List</summary> ##### 1. `@(name = value)` > The `@` was chosen to make them stand out from other attributes and because the "at" symbol is a subtle pneumonic for "attribute". Of course, other symbols could be used (e.g. `$`, `#`, etc.). ```rust #[derive(Reflect)] struct Slider { #[reflect(@(min = 0.0, max = 1.0), skip_serializing)] #[[reflect(@(bevy_editor::hint = "Range: 0.0 to 1.0"))] value: f32, } ``` ##### 2. `@name = value` > This is my personal favorite. ```rust #[derive(Reflect)] struct Slider { #[reflect(@min = 0.0, @max = 1.0, skip_serializing)] #[[reflect(@bevy_editor::hint = "Range: 0.0 to 1.0")] value: f32, } ``` ##### 3. `custom_attr(name = value)` > `custom_attr` can be anything. Other possibilities include `with` or `tag`. ```rust #[derive(Reflect)] struct Slider { #[reflect(custom_attr(min = 0.0, max = 1.0), skip_serializing)] #[[reflect(custom_attr(bevy_editor::hint = "Range: 0.0 to 1.0"))] value: f32, } ``` ##### 4. `reflect_attr(name = value)` ```rust #[derive(Reflect)] struct Slider { #[reflect(skip_serializing)] #[reflect_attr(min = 0.0, max = 1.0)] #[[reflect_attr(bevy_editor::hint = "Range: 0.0 to 1.0")] value: f32, } ``` </details> --- ## Changelog - Added support for custom attributes on reflected types (i.e. `#[reflect(@Foo::new("bar")]`) |
||
Gino Valente
|
40837501b4
|
examples: Add Dynamic Types reflection example (#13220)
# Objective Dynamic types can be tricky to understand and work with in bevy_reflect. There should be an example that shows what they are and how they're used. ## Solution Add a `Dynamic Types` reflection example. I'm planning to go through the reflection examples, adding new ones and updating old ones. And I think this walkthrough style tends to work best. Due to the amount of text and associated explanation, it might fit better in a dedicated reflection chapter of the WIP Bevy Book. However, I think it might be valuable to have some public-facing tutorials for these concepts. Let me know if there any thoughts or critiques with the example— both in content and this overall structure! ## Testing To test these changes, you can run the example locally: ``` cargo run --example dynamic_types ``` --- ## Changelog - Add `Dynamic Types` reflection example |
||
Gino Valente
|
0265436fff
|
bevy_reflect: Rename UntypedReflectDeserializer to ReflectDeserializer (#12721)
# Objective We have `ReflectSerializer` and `TypedReflectSerializer`. The former is the one users will most often use since the latter takes a bit more effort to deserialize. However, our deserializers are named `UntypedReflectDeserializer` and `TypedReflectDeserializer`. There is no obvious indication that `UntypedReflectDeserializer` must be used with `ReflectSerializer` since the names don't quite match up. ## Solution Rename `UntypedReflectDeserializer` back to `ReflectDeserializer` (initially changed as part of #5723). Also update the docs for both deserializers (as they were pretty out of date) and include doc examples. I also updated the docs for the serializers, too, just so that everything is consistent. --- ## Changelog - Renamed `UntypedReflectDeserializer` to `ReflectDeserializer` - Updated docs for `ReflectDeserializer`, `TypedReflectDeserializer`, `ReflectSerializer`, and `TypedReflectSerializer` ## Migration Guide `UntypedReflectDeserializer` has been renamed to `ReflectDeserializer`. Usages will need to be updated accordingly. ```diff - let reflect_deserializer = UntypedReflectDeserializer::new(®istry); + let reflect_deserializer = ReflectDeserializer::new(®istry); ``` |
||
James Liu
|
9e5db9abc7
|
Clean up type registrations (#12314)
# Objective Fix #12304. Remove unnecessary type registrations thanks to #4154. ## Solution Conservatively remove type registrations. Keeping the top level components, resources, and events, but dropping everything else that is a type of a member of those types. |
||
Gino Valente
|
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> |
||
Tristan Guichaoua
|
694c06f3d0
|
Inverse missing_docs logic (#11676)
# Objective Currently the `missing_docs` lint is allowed-by-default and enabled at crate level when their documentations is complete (see #3492). This PR proposes to inverse this logic by making `missing_docs` warn-by-default and mark crates with imcomplete docs allowed. ## Solution Makes `missing_docs` warn at workspace level and allowed at crate level when the docs is imcomplete. |
||
radiish
|
262846e702
|
reflect: TypePath part 2 (#8768)
# Objective
- Followup to #7184.
- ~Deprecate `TypeUuid` and remove its internal references.~ No longer
part of this PR.
- Use `TypePath` for the type registry, and (de)serialisation instead of
`std::any::type_name`.
- Allow accessing type path information behind proxies.
## Solution
- Introduce methods on `TypeInfo` and friends for dynamically querying
type path. These methods supersede the old `type_name` methods.
- Remove `Reflect::type_name` in favor of `DynamicTypePath::type_path`
and `TypeInfo::type_path_table`.
- Switch all uses of `std::any::type_name` in reflection, non-debugging
contexts to use `TypePath`.
---
## Changelog
- Added `TypePathTable` for dynamically accessing methods on `TypePath`
through `TypeInfo` and the type registry.
- Removed `type_name` from all `TypeInfo`-like structs.
- Added `type_path` and `type_path_table` methods to all `TypeInfo`-like
structs.
- Removed `Reflect::type_name` in favor of
`DynamicTypePath::reflect_type_path` and `TypeInfo::type_path`.
- Changed the signature of all `DynamicTypePath` methods to return
strings with a static lifetime.
## Migration Guide
- Rely on `TypePath` instead of `std::any::type_name` for all stability
guarantees and for use in all reflection contexts, this is used through
with one of the following APIs:
- `TypePath::type_path` if you have a concrete type and not a value.
- `DynamicTypePath::reflect_type_path` if you have an `dyn Reflect`
value without a concrete type.
- `TypeInfo::type_path` for use through the registry or if you want to
work with the represented type of a `DynamicFoo`.
- Remove `type_name` from manual `Reflect` implementations.
- Use `type_path` and `type_path_table` in place of `type_name` on
`TypeInfo`-like structs.
- Use `get_with_type_path(_mut)` over `get_with_type_name(_mut)`.
## Note to reviewers
I think if anything we were a little overzealous in merging #7184 and we
should take that extra care here.
In my mind, this is the "point of no return" for `TypePath` and while I
think we all agree on the design, we should carefully consider if the
finer details and current implementations are actually how we want them
moving forward.
For example [this incorrect `TypePath` implementation for
`String`](
|
||
Gino Valente
|
aeeb20ec4c
|
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> |
||
Carter Anderson
|
aefe1f0739
|
Schedule-First: the new and improved add_systems (#8079)
Co-authored-by: Mike <mike.hsu@gmail.com> |
||
Gino Valente
|
d30d3e752a |
bevy_reflect: Improve serialization format even more (#5723)
> Note: This is rebased off #4561 and can be viewed as a competitor to that PR. See `Comparison with #4561` section for details. # Objective The current serialization format used by `bevy_reflect` is both verbose and error-prone. Taking the following structs[^1] for example: ```rust // -- src/inventory.rs #[derive(Reflect)] struct Inventory { id: String, max_storage: usize, items: Vec<Item> } #[derive(Reflect)] struct Item { name: String } ``` Given an inventory of a single item, this would serialize to something like: ```rust // -- assets/inventory.ron { "type": "my_game::inventory::Inventory", "struct": { "id": { "type": "alloc::string::String", "value": "inv001", }, "max_storage": { "type": "usize", "value": 10 }, "items": { "type": "alloc::vec::Vec<alloc::string::String>", "list": [ { "type": "my_game::inventory::Item", "struct": { "name": { "type": "alloc::string::String", "value": "Pickaxe" }, }, }, ], }, }, } ``` Aside from being really long and difficult to read, it also has a few "gotchas" that users need to be aware of if they want to edit the file manually. A major one is the requirement that you use the proper keys for a given type. For structs, you need `"struct"`. For lists, `"list"`. For tuple structs, `"tuple_struct"`. And so on. It also ***requires*** that the `"type"` entry come before the actual data. Despite being a map— which in programming is almost always orderless by default— the entries need to be in a particular order. Failure to follow the ordering convention results in a failure to deserialize the data. This makes it very prone to errors and annoyances. ## Solution Using #4042, we can remove a lot of the boilerplate and metadata needed by this older system. Since we now have static access to type information, we can simplify our serialized data to look like: ```rust // -- assets/inventory.ron { "my_game::inventory::Inventory": ( id: "inv001", max_storage: 10, items: [ ( name: "Pickaxe" ), ], ), } ``` This is much more digestible and a lot less error-prone (no more key requirements and no more extra type names). Additionally, it is a lot more familiar to users as it follows conventional serde mechanics. For example, the struct is represented with `(...)` when serialized to RON. #### Custom Serialization Additionally, this PR adds the opt-in ability to specify a custom serde implementation to be used rather than the one created via reflection. For example[^1]: ```rust // -- src/inventory.rs #[derive(Reflect, Serialize)] #[reflect(Serialize)] struct Item { #[serde(alias = "id")] name: String } ``` ```rust // -- assets/inventory.ron { "my_game::inventory::Inventory": ( id: "inv001", max_storage: 10, items: [ ( id: "Pickaxe" ), ], ), }, ``` By allowing users to define their own serialization methods, we do two things: 1. We give more control over how data is serialized/deserialized to the end user 2. We avoid having to re-define serde's attributes and forcing users to apply both (e.g. we don't need a `#[reflect(alias)]` attribute). ### Improved Formats One of the improvements this PR provides is the ability to represent data in ways that are more conventional and/or familiar to users. Many users are familiar with RON so here are some of the ways we can now represent data in RON: ###### Structs ```js { "my_crate::Foo": ( bar: 123 ) } // OR { "my_crate::Foo": Foo( bar: 123 ) } ``` <details> <summary>Old Format</summary> ```js { "type": "my_crate::Foo", "struct": { "bar": { "type": "usize", "value": 123 } } } ``` </details> ###### Tuples ```js { "(f32, f32)": (1.0, 2.0) } ``` <details> <summary>Old Format</summary> ```js { "type": "(f32, f32)", "tuple": [ { "type": "f32", "value": 1.0 }, { "type": "f32", "value": 2.0 } ] } ``` </details> ###### Tuple Structs ```js { "my_crate::Bar": ("Hello World!") } // OR { "my_crate::Bar": Bar("Hello World!") } ``` <details> <summary>Old Format</summary> ```js { "type": "my_crate::Bar", "tuple_struct": [ { "type": "alloc::string::String", "value": "Hello World!" } ] } ``` </details> ###### Arrays It may be a bit surprising to some, but arrays now also use the tuple format. This is because they essentially _are_ tuples (a sequence of values with a fixed size), but only allow for homogenous types. Additionally, this is how RON handles them and is probably a result of the 32-capacity limit imposed on them (both by [serde](https://docs.rs/serde/latest/serde/trait.Serialize.html#impl-Serialize-for-%5BT%3B%2032%5D) and by [bevy_reflect](https://docs.rs/bevy/latest/bevy/reflect/trait.GetTypeRegistration.html#impl-GetTypeRegistration-for-%5BT%3B%2032%5D)). ```js { "[i32; 3]": (1, 2, 3) } ``` <details> <summary>Old Format</summary> ```js { "type": "[i32; 3]", "array": [ { "type": "i32", "value": 1 }, { "type": "i32", "value": 2 }, { "type": "i32", "value": 3 } ] } ``` </details> ###### Enums To make things simple, I'll just put a struct variant here, but the style applies to all variant types: ```js { "my_crate::ItemType": Consumable( name: "Healing potion" ) } ``` <details> <summary>Old Format</summary> ```js { "type": "my_crate::ItemType", "enum": { "variant": "Consumable", "struct": { "name": { "type": "alloc::string::String", "value": "Healing potion" } } } } ``` </details> ### Comparison with #4561 This PR is a rebased version of #4561. The reason for the split between the two is because this PR creates a _very_ different scene format. You may notice that the PR descriptions for either PR are pretty similar. This was done to better convey the changes depending on which (if any) gets merged first. If #4561 makes it in first, I will update this PR description accordingly. --- ## Changelog * Re-worked serialization/deserialization for reflected types * Added `TypedReflectDeserializer` for deserializing data with known `TypeInfo` * Renamed `ReflectDeserializer` to `UntypedReflectDeserializer` * ~~Replaced usages of `deserialize_any` with `deserialize_map` for non-self-describing formats~~ Reverted this change since there are still some issues that need to be sorted out (in a separate PR). By reverting this, crates like `bincode` can throw an error when attempting to deserialize non-self-describing formats (`bincode` results in `DeserializeAnyNotSupported`) * Structs, tuples, tuple structs, arrays, and enums are now all de/serialized using conventional serde methods ## Migration Guide * This PR reduces the verbosity of the scene format. Scenes will need to be updated accordingly: ```js // Old format { "type": "my_game::item::Item", "struct": { "id": { "type": "alloc::string::String", "value": "bevycraft:stone", }, "tags": { "type": "alloc::vec::Vec<alloc::string::String>", "list": [ { "type": "alloc::string::String", "value": "material" }, ], }, } // New format { "my_game::item::Item": ( id: "bevycraft:stone", tags: ["material"] ) } ``` [^1]: Some derives omitted for brevity. |
||
ira
|
992681b59b |
Make Resource trait opt-in, requiring #[derive(Resource)] V2 (#5577)
*This PR description is an edited copy of #5007, written by @alice-i-cecile.* # Objective Follow-up to https://github.com/bevyengine/bevy/pull/2254. The `Resource` trait currently has a blanket implementation for all types that meet its bounds. While ergonomic, this results in several drawbacks: * it is possible to make confusing, silent mistakes such as inserting a function pointer (Foo) rather than a value (Foo::Bar) as a resource * it is challenging to discover if a type is intended to be used as a resource * we cannot later add customization options (see the [RFC](https://github.com/bevyengine/rfcs/blob/main/rfcs/27-derive-component.md) for the equivalent choice for Component). * dependencies can use the same Rust type as a resource in invisibly conflicting ways * raw Rust types used as resources cannot preserve privacy appropriately, as anyone able to access that type can read and write to internal values * we cannot capture a definitive list of possible resources to display to users in an editor ## Notes to reviewers * Review this commit-by-commit; there's effectively no back-tracking and there's a lot of churn in some of these commits. *ira: My commits are not as well organized :')* * I've relaxed the bound on Local to Send + Sync + 'static: I don't think these concerns apply there, so this can keep things simple. Storing e.g. a u32 in a Local is fine, because there's a variable name attached explaining what it does. * I think this is a bad place for the Resource trait to live, but I've left it in place to make reviewing easier. IMO that's best tackled with https://github.com/bevyengine/bevy/issues/4981. ## Changelog `Resource` is no longer automatically implemented for all matching types. Instead, use the new `#[derive(Resource)]` macro. ## Migration Guide Add `#[derive(Resource)]` to all types you are using as a resource. If you are using a third party type as a resource, wrap it in a tuple struct to bypass orphan rules. Consider deriving `Deref` and `DerefMut` to improve ergonomics. `ClearColor` no longer implements `Component`. Using `ClearColor` as a component in 0.8 did nothing. Use the `ClearColorConfig` in the `Camera3d` and `Camera2d` components instead. Co-authored-by: Alice <alice.i.cecile@gmail.com> Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: devil-ira <justthecooldude@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
||
Gino Valente
|
15826d6019 |
bevy_reflect: Reflect enums (#4761)
# Objective
> This is a revival of #1347. Credit for the original PR should go to @Davier.
Currently, enums are treated as `ReflectRef::Value` types by `bevy_reflect`. Obviously, there needs to be better a better representation for enums using the reflection API.
## Solution
Based on prior work from @Davier, an `Enum` trait has been added as well as the ability to automatically implement it via the `Reflect` derive macro. This allows enums to be expressed dynamically:
```rust
#[derive(Reflect)]
enum Foo {
A,
B(usize),
C { value: f32 },
}
let mut foo = Foo::B(123);
assert_eq!("B", foo.variant_name());
assert_eq!(1, foo.field_len());
let new_value = DynamicEnum::from(Foo::C { value: 1.23 });
foo.apply(&new_value);
assert_eq!(Foo::C{value: 1.23}, foo);
```
### Features
#### Derive Macro
Use the `#[derive(Reflect)]` macro to automatically implement the `Enum` trait for enum definitions. Optionally, you can use `#[reflect(ignore)]` with both variants and variant fields, just like you can with structs. These ignored items will not be considered as part of the reflection and cannot be accessed via reflection.
```rust
#[derive(Reflect)]
enum TestEnum {
A,
// Uncomment to ignore all of `B`
// #[reflect(ignore)]
B(usize),
C {
// Uncomment to ignore only field `foo` of `C`
// #[reflect(ignore)]
foo: f32,
bar: bool,
},
}
```
#### Dynamic Enums
Enums may be created/represented dynamically via the `DynamicEnum` struct. The main purpose of this struct is to allow enums to be deserialized into a partial state and to allow dynamic patching. In order to ensure conversion from a `DynamicEnum` to a concrete enum type goes smoothly, be sure to add `FromReflect` to your derive macro.
```rust
let mut value = TestEnum::A;
// Create from a concrete instance
let dyn_enum = DynamicEnum::from(TestEnum::B(123));
value.apply(&dyn_enum);
assert_eq!(TestEnum::B(123), value);
// Create a purely dynamic instance
let dyn_enum = DynamicEnum::new("TestEnum", "A", ());
value.apply(&dyn_enum);
assert_eq!(TestEnum::A, value);
```
#### Variants
An enum value is always represented as one of its variants— never the enum in its entirety.
```rust
let value = TestEnum::A;
assert_eq!("A", value.variant_name());
// Since we are using the `A` variant, we cannot also be the `B` variant
assert_ne!("B", value.variant_name());
```
All variant types are representable within the `Enum` trait: unit, struct, and tuple.
You can get the current type like:
```rust
match value.variant_type() {
VariantType::Unit => println!("A unit variant!"),
VariantType::Struct => println!("A struct variant!"),
VariantType::Tuple => println!("A tuple variant!"),
}
```
> Notice that they don't contain any values representing the fields. These are purely tags.
If a variant has them, you can access the fields as well:
```rust
let mut value = TestEnum::C {
foo: 1.23,
bar: false
};
// Read/write specific fields
*value.field_mut("bar").unwrap() = true;
// Iterate over the entire collection of fields
for field in value.iter_fields() {
println!("{} = {:?}", field.name(), field.value());
}
```
#### Variant Swapping
It might seem odd to group all variant types under a single trait (why allow `iter_fields` on a unit variant?), but the reason this was done ~~is to easily allow *variant swapping*.~~ As I was recently drafting up the **Design Decisions** section, I discovered that other solutions could have been made to work with variant swapping. So while there are reasons to keep the all-in-one approach, variant swapping is _not_ one of them.
```rust
let mut value: Box<dyn Enum> = Box::new(TestEnum::A);
value.set(Box::new(TestEnum::B(123))).unwrap();
```
#### Serialization
Enums can be serialized and deserialized via reflection without needing to implement `Serialize` or `Deserialize` themselves (which can save thousands of lines of generated code). Below are the ways an enum can be serialized.
> Note, like the rest of reflection-based serialization, the order of the keys in these representations is important!
##### Unit
```json
{
"type": "my_crate::TestEnum",
"enum": {
"variant": "A"
}
}
```
##### Tuple
```json
{
"type": "my_crate::TestEnum",
"enum": {
"variant": "B",
"tuple": [
{
"type": "usize",
"value": 123
}
]
}
}
```
<details>
<summary>Effects on Option</summary>
This ends up making `Option` look a little ugly:
```json
{
"type": "core::option::Option<usize>",
"enum": {
"variant": "Some",
"tuple": [
{
"type": "usize",
"value": 123
}
]
}
}
```
</details>
##### Struct
```json
{
"type": "my_crate::TestEnum",
"enum": {
"variant": "C",
"struct": {
"foo": {
"type": "f32",
"value": 1.23
},
"bar": {
"type": "bool",
"value": false
}
}
}
}
```
## Design Decisions
<details>
<summary><strong>View Section</strong></summary>
This section is here to provide some context for why certain decisions were made for this PR, alternatives that could have been used instead, and what could be improved upon in the future.
### Variant Representation
One of the biggest decisions was to decide on how to represent variants. The current design uses a "all-in-one" design where unit, tuple, and struct variants are all simultaneously represented by the `Enum` trait. This is not the only way it could have been done, though.
#### Alternatives
##### 1. Variant Traits
One way of representing variants would be to define traits for each variant, implementing them whenever an enum featured at least one instance of them. This would allow us to define variants like:
```rust
pub trait Enum: Reflect {
fn variant(&self) -> Variant;
}
pub enum Variant<'a> {
Unit,
Tuple(&'a dyn TupleVariant),
Struct(&'a dyn StructVariant),
}
pub trait TupleVariant {
fn field_len(&self) -> usize;
// ...
}
```
And then do things like:
```rust
fn get_tuple_len(foo: &dyn Enum) -> usize {
match foo.variant() {
Variant::Tuple(tuple) => tuple.field_len(),
_ => panic!("not a tuple variant!")
}
}
```
The reason this PR does not go with this approach is because of the fact that variants are not separate types. In other words, we cannot implement traits on specific variants— these cover the *entire* enum. This means we offer an easy footgun:
```rust
let foo: Option<i32> = None;
let my_enum = Box::new(foo) as Box<dyn TupleVariant>;
```
Here, `my_enum` contains `foo`, which is a unit variant. However, since we need to implement `TupleVariant` for `Option` as a whole, it's possible to perform such a cast. This is obviously wrong, but could easily go unnoticed. So unfortunately, this makes it not a good candidate for representing variants.
##### 2. Variant Structs
To get around the issue of traits necessarily needing to apply to both the enum and its variants, we could instead use structs that are created on a per-variant basis. This was also considered but was ultimately [[removed](
|
||
Jakob Hellermann
|
49ff42cc69 |
fix new clippy lints (#5160)
# Objective - Nightly clippy lints should be fixed before they get stable and break CI ## Solution - fix new clippy lints - ignore `significant_drop_in_scrutinee` since it isn't relevant in our loop https://github.com/rust-lang/rust-clippy/issues/8987 ```rust for line in io::stdin().lines() { ... } ``` Co-authored-by: Jakob Hellermann <hellermann@sipgate.de> |
||
Félix Lescaudey de Maneville
|
f000c2b951 |
Clippy improvements (#4665)
# Objective Follow up to my previous MR #3718 to add new clippy warnings to bevy: - [x] [~~option_if_let_else~~](https://rust-lang.github.io/rust-clippy/master/#option_if_let_else) (reverted) - [x] [redundant_else](https://rust-lang.github.io/rust-clippy/master/#redundant_else) - [x] [match_same_arms](https://rust-lang.github.io/rust-clippy/master/#match_same_arms) - [x] [semicolon_if_nothing_returned](https://rust-lang.github.io/rust-clippy/master/#semicolon_if_nothing_returned) - [x] [explicit_iter_loop](https://rust-lang.github.io/rust-clippy/master/#explicit_iter_loop) - [x] [map_flatten](https://rust-lang.github.io/rust-clippy/master/#map_flatten) There is one commit per clippy warning, and the matching flags are added to the CI execution. To test the CI execution you may run `cargo run -p ci -- clippy` at the root. I choose the add the flags in the `ci` tool crate to avoid having them in every `lib.rs` but I guess it could become an issue with suprise warnings coming up after a commit/push Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
||
Mark Schmale
|
1ba7429371 |
Doc/module style doc blocks for examples (#4438)
# Objective Provide a starting point for #3951, or a partial solution. Providing a few comment blocks to discuss, and hopefully find better one in the process. ## Solution Since I am pretty new to pretty much anything in this context, I figured I'd just start with a draft for some file level doc blocks. For some of them I found more relevant details (or at least things I considered interessting), for some others there is less. ## Changelog - Moved some existing comments from main() functions in the 2d examples to the file header level - Wrote some more comment blocks for most other 2d examples TODO: - [x] 2d/sprite_sheet, wasnt able to come up with something good yet - [x] all other example groups... Also: Please let me know if the commit style is okay, or to verbose. I could certainly squash these things, or add more details if needed. I also hope its okay to raise this PR this early, with just a few files changed. Took me long enough and I dont wanted to let it go to waste because I lost motivation to do the whole thing. Additionally I am somewhat uncertain over the style and contents of the commets. So let me know what you thing please. |
||
MrGVSV
|
acbee7795d |
bevy_reflect: Reflect arrays (#4701)
# Objective > ℹ️ **Note**: This is a rebased version of #2383. A large portion of it has not been touched (only a few minor changes) so that any additional discussion may happen here. All credit should go to @NathanSWard for their work on the original PR. - Currently reflection is not supported for arrays. - Fixes #1213 ## Solution * Implement reflection for arrays via the `Array` trait. * Note, `Array` is different from `List` in the way that you cannot push elements onto an array as they are statically sized. * Now `List` is defined as a sub-trait of `Array`. --- ## Changelog * Added the `Array` reflection trait * Allows arrays up to length 32 to be reflected via the `Array` trait ## Migration Guide * The `List` trait now has the `Array` supertrait. This means that `clone_dynamic` will need to specify which version to use: ```rust // Before let cloned = my_list.clone_dynamic(); // After let cloned = List::clone_dynamic(&my_list); ``` * All implementers of `List` will now need to implement `Array` (this mostly involves moving the existing methods to the `Array` impl) Co-authored-by: NathanW <nathansward@comcast.net> Co-authored-by: MrGVSV <49806985+MrGVSV@users.noreply.github.com> |
||
danieleades
|
d8974e7c3d |
small and mostly pointless refactoring (#2934)
What is says on the tin. This has got more to do with making `clippy` slightly more *quiet* than it does with changing anything that might greatly impact readability or performance. that said, deriving `Default` for a couple of structs is a nice easy win |
||
Michael Dorst
|
e6bce74220 |
Fix doc_markdown lints in examples (#3486)
#3457 adds the `doc_markdown` clippy lint, which checks doc comments to make sure code identifiers are escaped with backticks. This causes a lot of lint errors, so this is one of a number of PR's that will fix those lint errors one crate at a time. This PR fixes lints in the `examples` folder. |
||
François
|
b724a0f586 |
Down with the system! (#2496)
# Objective - Remove all the `.system()` possible. - Check for remaining missing cases. ## Solution - Remove all `.system()`, fix compile errors - 32 calls to `.system()` remains, mostly internals, the few others should be removed after #2446 |
||
bjorn3
|
6d6bc2a8b4 |
Merge AppBuilder into App (#2531)
This is extracted out of eb8f973646476b4a4926ba644a77e2b3a5772159 and includes some additional changes to remove all references to AppBuilder and fix examples that still used App::build() instead of App::new(). In addition I didn't extract the sub app feature as it isn't ready yet. You can use `git diff --diff-filter=M eb8f973646476b4a4926ba644a77e2b3a5772159` to find all differences in this PR. The `--diff-filtered=M` filters all files added in the original commit but not in this commit away. Co-Authored-By: Carter Anderson <mcanders1@gmail.com> |
||
François
|
e3fb23d4d3 |
add documentation on LogPlugin and more log usage (#1973)
Fixes #1895 Changed most `println` to `info` in examples, some to `warn` when it was useful to differentiate from other more noisy logs. Added doc on `LogPlugin`, how to configure it, and why (and how) you may need to disable it |
||
Carter Anderson
|
b17f8a4bce |
format comments (#1612)
Uses the new unstable comment formatting features added to rustfmt.toml. |
||
MinerSebas
|
8f363544ad |
Reorder Imports in Examples (#1598)
This only affected 2 Examples: * `generic_reflection`: For some reason, a `pub use` statement was used. This was removed, and alphabetically ordered. * `wireframe`: This example used the `bevy_internal` crate directly. Changed to use `bevy` instead. All other Example Imports are correct. One potential subjective change is the `removel_detection` example. Unlike all other Examples, it has its (first) explanatory comment before the Imports. |
||
TehPers
|
5e7456115a
|
Implement Reflect for tuples up to length 12 (#1218)
Add Reflect impls for tuples up to length 12 |
||
Carter Anderson
|
841755aaf2
|
Adopt a Fetch pattern for SystemParams (#1074) | ||
Nathan Stocks
|
3cee95e59a
|
Rename reflect 'hash' method to 'reflect_hash' and partial_eq to reflect_partial_eq (#954)
* Rename reflect 'hash' method to 'reflect_hash' to avoid colliding with std:#️⃣:Hash::hash to resolve #943. * Rename partial_eq to reflect_partial_eq to avoid collisions with implementations of PartialEq on primitives. |
||
Carter Anderson
|
72b2fc9843
|
Bevy Reflection (#926)
Bevy Reflection |