This adds documentation for:
- The trait methods of `Reflect` and its subtraits
- The `partial_eq` and `apply` functions for `Map` et al.
- `DynamicList` and `DynamicMap`
- `TypeRegistry` and related types & traits
- `GetPath`, including an explanation of path string syntax
among other things.
Still to be documented are the various macros and `bevy_reflect::serde`.
# Objective
These traits are undocumented on `main`.
## Solution
Now they have docs! Included are examples for each trait and their corresponding `GetTypeField` trait. The docs also mention that `#[derive(Reflect)]` will automatically derive the correct subtrait on structs and tuple structs.
Dynamic types (`DynamicStruct`, `DynamicTupleStruct`, `DynamicTuple`, `DynamicList` and `DynamicMap`) are used when deserializing scenes, but currently they can only be applied to existing concrete types. This leads to issues when trying to spawn non trivial deserialized scene.
For components, the issue is avoided by requiring that reflected components implement ~~`FromResources`~~ `FromWorld` (or `Default`). When spawning, a new concrete type is created that way, and the dynamic type is applied to it. Unfortunately, some components don't have any valid implementation of these traits.
In addition, any `Vec` or `HashMap` inside a component will panic when a dynamic type is pushed into it (for instance, `Text` panics when adding a text section).
To solve this issue, this PR adds the `FromReflect` trait that creates a concrete type from a dynamic type that represent it, derives the trait alongside the `Reflect` trait, drops the ~~`FromResources`~~ `FromWorld` requirement on reflected components, ~~and enables reflection for UI and Text bundles~~. It also adds the requirement that fields ignored with `#[reflect(ignore)]` implement `Default`, since we need to initialize them somehow.
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
- Avoid usages of `format!` that ~immediately get passed to another `format!`. This avoids a temporary allocation and is just generally cleaner.
## Solution
- `bevy_derive::shader_defs` does a `format!("{}", val.to_string())`, which is better written as just `format!("{}", val)`
- `bevy_diagnostic::log_diagnostics_plugin` does a `format!("{:>}", format!(...))`, which is better written as `format!("{:>}", format_args!(...))`
- `bevy_ecs::schedule` does `tracing::info!(..., name = &*format!("{:?}", val))`, which is better written with the tracing shorthand `tracing::info!(..., name = ?val)`
- `bevy_reflect::reflect` does `f.write_str(&format!(...))`, which is better written as `write!(f, ...)` (this could also be written using `f.debug_tuple`, but I opted to maintain alt debug behavior)
- `bevy_reflect::serde::{ser, de}` do `serde::Error::custom(format!(...))`, which is better written as `Error::custom(format_args!(...))`, as `Error::custom` takes `impl Display` and just immediately calls `format!` again
fix a few dead links
* Links in `Input` missed a refactor
* `Reflect::downcast` can't use the intra doc link format, as it's not a link to a trait function, but to a function implemented on `dyn Reflect`
noticed in https://github.com/bevyengine/bevy/pull/1781#discussion_r619777879
Fixes#1100
Implementors must make sure that `Reflect::any` and `Reflect::any_mut` both return the `self` reference passed in (both for logical correctness and downcast safety).
* 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.
