Test your iced applications in headless mode.

Basic Usage

Let's assume we want to test the classical counter interface.

First, we will want to create a [Simulator] of our interface:

# struct Counter { value: i64 }
# impl Counter {
#    pub fn view(&self) -> iced_runtime::core::Element<(), iced_runtime::core::Theme, iced_renderer::Renderer> { unimplemented!() }
# }
use iced_test::simulator;

let mut counter = Counter { value: 0 };
let mut ui = simulator(counter.view());

Now we can simulate a user interacting with our interface. Let's use [Simulator::click] to click the counter buttons:

# struct Counter { value: i64 }
# impl Counter {
#    pub fn view(&self) -> iced_runtime::core::Element<(), iced_runtime::core::Theme, iced_renderer::Renderer> { unimplemented!() }
# }
# use iced_test::simulator;
#
# let mut counter = Counter { value: 0 };
# let mut ui = simulator(counter.view());
#
let _ = ui.click("+");
let _ = ui.click("+");
let _ = ui.click("-");

[Simulator::click] takes a type implementing the [Selector] trait. A [Selector] describes a way to query the widgets of an interface. In this case, we leverage the [Selector] implementation of &str, which selects a widget by the text it contains.

We can now process any messages produced by these interactions and then assert that the final value of our counter is indeed 1!

# struct Counter { value: i64 }
# impl Counter {
#    pub fn update(&mut self, message: ()) {}
#    pub fn view(&self) -> iced_runtime::core::Element<(), iced_runtime::core::Theme, iced_renderer::Renderer> { unimplemented!() }
# }
# use iced_test::simulator;
#
# let mut counter = Counter { value: 0 };
# let mut ui = simulator(counter.view());
#
# let _ = ui.click("+");
# let _ = ui.click("+");
# let _ = ui.click("-");
#
for message in ui.into_messages() {
    counter.update(message);
}

assert_eq!(counter.value, 1);

We can even rebuild the interface to make sure the counter displays the proper value with [Simulator::find]:

# struct Counter { value: i64 }
# impl Counter {
#    pub fn view(&self) -> iced_runtime::core::Element<(), iced_runtime::core::Theme, iced_renderer::Renderer> { unimplemented!() }
# }
# use iced_test::simulator;
#
# let mut counter = Counter { value: 0 };
let mut ui = simulator(counter.view());

assert!(ui.find("1").is_ok(), "Counter should display 1!");

And that's it! That's the gist of testing iced applications!

[Simulator] contains additional operations you can use to simulate more interactions—like tap_key or typewrite—and even perform snapshot testing!

toddy-iced-test 0.6.2

Basic Usage