forestia/bevy
2
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

add informative panic message when adding render commands to a DrawFunctions that does not exist (#3924)

Browse Source 
# Objective

If a user attempts to `.add_render_command::<P, C>()` on a world that does not contain `DrawFunctions<P>`, the engine panics with a generic `Option::unwrap` message:

```
thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', /[redacted]/bevy/crates/bevy_render/src/render_phase/draw.rs:318:76
```

## Solution

This PR adds a panic message describing the problem:

```
thread 'main' panicked at 'DrawFunctions<outline::MeshStencil> must be added to the world as a resource before adding render commands to it', /[redacted]/bevy/crates/bevy_render/src/render_phase/draw.rs:322:17
```
This commit is contained in:
dataphract 2022-02-13 00:14:37 +00:00
parent d305e4f026
commit 5bb4201f2e
1 changed files with 10 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
crates/bevy_render/src/render_phase/draw.rs
View File

@ -315,7 +315,16 @@ impl AddRenderCommand for App {
<C::Param as SystemParam>::Fetch: ReadOnlySystemParamFetch, <C::Param as SystemParam>::Fetch: ReadOnlySystemParamFetch,
{ {
let draw_function = RenderCommandState::<P, C>::new(&mut self.world); let draw_function = RenderCommandState::<P, C>::new(&mut self.world);
let draw_functions = self.world.get_resource::<DrawFunctions<P>>().unwrap(); let draw_functions = self
.world
.get_resource::<DrawFunctions<P>>()
.unwrap_or_else(|| {
panic!(
"DrawFunctions<{}> must be added to the world as a resource \
before adding render commands to it",
std::any::type_name::<P>(),
);
});
draw_functions.write().add_with::<C, _>(draw_function); draw_functions.write().add_with::<C, _>(draw_function);
self self
} }