Slint UI Testing Examples

Example applications built with Slint, each with a suite of Python tests that use Slint UI Testing to launch the application, find UI elements, interact with them, and verify the results.

Example	Language	Shows
rust-todo	Rust	Lists and find_all, queries by role and label, checkboxes, enabled state, tracking elements
cpp-temperature-converter	C++	Text input, parametrized tests, error states, keyboard events
node-signup	Node.js	Forms, elements in if conditions, quitting the application
python-tip-calculator	Python	Spin boxes, increment and decrement actions, value ranges

Each example is self-contained. Copy its directory as a starting point for your own project.

Prerequisites

• uv, which also provides Python.
• For the Rust and C++ examples: a Rust toolchain. The C++ example builds Slint from source.
• For the C++ example: CMake 3.21 or newer and a C++20 compiler.
• For the Node.js example: Node.js 20 or newer.
• An access token for Slint UI Testing's package index at testing.slint.dev.

Set up access to slint-testing

The slint_testing Python package is distributed through Slint's package index at testing.slint.dev. Give your token to uv once per machine:

uv auth login https://testing.slint.dev/simple/ --token <TOKEN>

Each example's pyproject.toml points uv at that index for slint-testing only. The URL holds no token, so it's safe to commit.

Run the tests

cd rust-todo    # or any other example
uv run pytest -v

The first run builds the application, which takes a while for the C++ example because Slint gets compiled. When a test fails, a screenshot of the window is saved in screenshots/.

How it works

The application needs system testing support, which is left out of regular builds so it isn't part of the application you ship:

• In Rust, the application's system-testing Cargo feature enables the system-testing feature of the slint crate. The tests build with that feature.
• In C++, the tests configure CMake with -DSLINT_FEATURE_SYSTEM_TESTING=ON.
• In Node.js, slint-ui-dev is a dev dependency next to slint-ui.
• In Python, slint[dev] is in the dev dependency group next to slint.

For Rust and C++, the tests also set the SLINT_EMIT_DEBUG_INFO=1 environment variable during the build, so that the element ids from the .slint files, such as AppWindow::add-button, are available to the tests. Node.js and Python compile .slint files at run time and always keep the element ids.

slint_testing.Application launches the application and waits for its first window to connect back. Each test gets a fresh instance of the application through pytest fixtures in tests/conftest.py.

See the Slint UI Testing documentation for the full API.

Continuous integration

The CI workflow runs the tests on Linux, macOS, and Windows. It reads the token from the SLINT_TESTING_TOKEN repository secret and passes it to uv through the UV_INDEX_SLINT_PRIVATE_USERNAME and UV_INDEX_SLINT_PRIVATE_PASSWORD environment variables. On Linux, a virtual X display lets the application show its windows.

License

The examples are available under the MIT license.