### What
From the [lint
description](https://rust-lang.github.io/rust-clippy/master/index.html?search=or_fu#or_fun_call):
> The function will always be called. This is only bad if it allocates
or does some non-trivial amount of work.
But also:
> If the function has side-effects, not calling it will change the
semantic of the program, but you shouldn’t rely on that.
>
> The lint also cannot figure out whether the function you call is
actually expensive to call or not.
Still worth it to keep our happy paths clean, imo.
This PR is a continuation of #4915 by @frederik-uni and @lucasmerlin
that introduces support for keeping egui content within the 'safe area'
on iOS (avoiding the notch / dynamic island / menu bar etc.), with the
following changes:
- `SafeArea` now wraps `MarginF32` and has been renamed to
`SafeAreaInsets` to clarify its purpose.
- `InputState::screen_rect` is now marked as deprecated in favour of
either `viewport_rect` (which contains the entire screen), or
`content_rect` (which is the viewport rect with the safe area insets
removed).
- I added some comments to the safe area insets logic pointing out the
[safe area API coming in winit
v0.31](https://github.com/rust-windowing/winit/issues/3910).
---------
Co-authored-by: frederik-uni <147479464+frederik-uni@users.noreply.github.com>
Co-authored-by: Lucas Meurer <hi@lucasmerlin.me>
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
The allows us to pass any state to the ui closure. While it is possible
to just store state in the closure itself, accessing that state after
the harness was created to e.g. read or modify it would require interior
mutability. With this change there are new `Harness::new_state`,
`Harness::run_state`, ... methods that allow passing state on each run.
This builds on top of #5301, which should be merged first
---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
This adds a `Harness::new_ui`, which accepts a Ui closure and shows the
ui in a central panel. One big benefit is that this allows us to add a
fit_contents method that can run the ui closure with a sizing pass and
resize the "screen" based on the content size.
I also used this to add a snapshot test for the rendering_test at
different scales.
This should hopefully make it easier for egui contributors and
egui_kittest users to understand the snapshot tests
* [X] I have followed the instructions in the PR template
- closes#3491
- closes#3926
This adds a testing library to egui based on
[kittest](https://github.com/rerun-io/kittest). Kittest is a new
[AccessKit](https://github.com/AccessKit/accesskit/)-based testing
library. The api is inspired by the js
[testing-library](https://testing-library.com/) where the idea is also
to query the dom based on accessibility attributes.
We made kittest with egui in mind but it should work with any rust gui
framework with AccessKit support.
It currently has support for:
- running the egui app, frame by frame
- building the AccessKit tree
- ergonomic queries via kittest
- via e.g. get_by_name, get_by_role
- simulating events based on the accesskit node id
- creating arbitrary events based on Harness::input_mut
- rendering screenshots via wgpu
- snapshot tests with these screenshots
A simple test looks like this:
```rust
fn main() {
let mut checked = false;
let app = |ctx: &Context| {
CentralPanel::default().show(ctx, |ui| {
ui.checkbox(&mut checked, "Check me!");
});
};
let mut harness = Harness::builder().with_size(egui::Vec2::new(200.0, 100.0)).build(app);
let checkbox = harness.get_by_name("Check me!");
assert_eq!(checkbox.toggled(), Some(Toggled::False));
checkbox.click();
harness.run();
let checkbox = harness.get_by_name("Check me!");
assert_eq!(checkbox.toggled(), Some(Toggled::True));
// You can even render the ui and do image snapshot tests
#[cfg(all(feature = "wgpu", feature = "snapshot"))]
egui_kittest::image_snapshot(&egui_kittest::wgpu::TestRenderer::new().render(&harness), "readme_example");
}
```
~Since getting wgpu to run in ci is a hassle, I'm taking another shot at
creating a software renderer for egui (ideally without a huge dependency
like skia)~ (this didn't work as well as I hoped and it turns out in CI
you can just run tests on a mac runner which comes with a real GPU)
Here is a example of a failed snapshot test in ci, it will say which
snapshot failed and upload an artifact with the before / after and diff
images:
https://github.com/emilk/egui/actions/runs/11183049487/job/31090724606?pr=5166
