# Objective
- Follow-up of #13184 :)
- We use `ui_test` to test compiler errors for our custom macros.
- There are four crates related to compile fail tests
- `bevy_ecs_compile_fail_tests`, `bevy_macros_compile_fail_tests`, and
`bevy_reflect_compile_fail_tests`, which actually test the macros.
-
[`bevy_compile_test_utils`](64c1c65783/crates/bevy_compile_test_utils),
which provides helpers and common patterns for these tests.
- All of these crates reside within the `crates` directory.
- This can be confusing, especially for newcomers. All of the other
folders in `crates` are actual published libraries, except for these 4.
## Solution
- Move all compile fail tests to a `compile_fail` folder under their
corresponding crate.
- E.g. `crates/bevy_ecs_compile_fail_tests` would be moved to
`crates/bevy_ecs/compile_fail`.
- Move `bevy_compile_test_utils` to `tools/compile_fail_utils`.
There are a few benefits to this approach:
1. An internal testing detail is less intrusive (and confusing) for
those who just want to browse the public Bevy interface.
2. Follows a pre-existing approach of organizing related crates inside a
larger crate's folder.
- See `bevy_gizmos/macros` for an example.
4. Makes consistent the terms `compile_test`, `compile_fail`, and
`compile_fail_test` in code. It's all just `compile_fail` now, because
we are specifically testing the error messages on compiler failures.
- To be clear it can still be referred to by these terms in comments and
speech, just the names of the crates and the CI command are now
consistent.
## Testing
Run the compile fail CI command:
```shell
cargo run -p ci -- compile-fail
```
If it still passes, then my refactor was successful.
# Objective
Make compile fail tests less likely to break with new Rust versions.
Closes#12627
## Solution
Switch from [`trybuild`](https://github.com/dtolnay/trybuild) to
[`ui_test`](https://github.com/oli-obk/ui_test).
## TODO
- [x] Update `bevy_ecs_compile_fail_tests`
- [x] Update `bevy_macros_compile_fail_tests`
- [x] Update `bevy_reflect_compile_fail_tests`
---------
Co-authored-by: Oli Scherer <github35764891676564198441@oli-obk.de>
Co-authored-by: BD103 <59022059+BD103@users.noreply.github.com>
# Objective
bevy_ecs has several compile_fail tests that assert lifetime safety. In the past, these tests have been green for the wrong reasons (see e.g. #2984). This PR makes sure, that they will fail if the compiler error changes.
## Solution
Use [trybuild](https://crates.io/crates/trybuild) to assert the compiler errors.
The UI tests are in a separate crate that is not part of the Bevy workspace. This is to ensure that they do not break Bevy's crater builds. The tests get executed by the CI workflow on the stable toolchain.
