bevy/crates/bevy_render
MiniaczQ e312da8c52
Reduce runtime panics through SystemParam validation (#15276)
# Objective

The goal of this PR is to introduce `SystemParam` validation in order to
reduce runtime panics.

Fixes #15265

## Solution

`SystemParam` now has a new method `validate_param(...) -> bool`, which
takes immutable variants of `get_param` arguments. The returned value
indicates whether the parameter can be acquired from the world. If
parameters cannot be acquired for a system, it won't be executed,
similarly to run conditions. This reduces panics when using params like
`Res`, `ResMut`, etc. as well as allows for new, ergonomic params like
#15264 or #15302.

Param validation happens at the level of executors. All validation
happens directly before executing a system, in case of normal systems
they are skipped, in case of conditions they return false.

Warning about system skipping is primitive and subject to change in
subsequent PRs.

## Testing

Two executor tests check that all executors:
- skip systems which have invalid parameters:
  - piped systems get skipped together,
  - dependent systems still run correctly,
- skip systems with invalid run conditions:
  - system conditions have invalid parameters,
  - system set conditions have invalid parameters.
2024-09-23 16:54:21 +00:00
..
macros Allow to expect (adopted) (#15301) 2024-09-20 19:16:42 +00:00
src Reduce runtime panics through SystemParam validation (#15276) 2024-09-23 16:54:21 +00:00
Cargo.toml Spirv passthrough main (adopted, part deux) (#15352) 2024-09-22 14:51:14 +00:00
README.md Add README.md to all crates (#13184) 2024-05-02 18:56:00 +00:00

Bevy Render

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