Using Simulations

Simulations are meant for test arrangement, sometimes called “test setup”. For example, sending an API request to prepare resources, triggering a push notification, or simulating location updates.

Using the tester fixture

The tester fixture provides the skeleton to run a simulation in your tests. To run a simulation, you simply need to use with the context manager syntax.

def test_example(tester: Tester):
    with tester.simulations.location_update(lat=0.001, lng=0.001): # <-- trigger a simulation
        pass # <-- perform assertions here

There are various available simulations in tester.simulations that you can use:

• location_update: Triggering location updates.

• push_notification: Pushing a notification to the app.

Writing a new Simulation

Similar to Screen, the purpose of having Simulation is to make your logic readable and reusable. To write a new simulation, you just need to subclass Simulation and place it under e2e_ext/simulations.

from e2e_ext.core import Simulation

class PrepareDataSimulation(Simulation):
    def run(self, **kwargs):
        pass # <-- Implement your logic here

Creating a new Simulation

For convenience, we provide the CLI usage for you to quickly create a new simulation from templates.

$ e2e new simulation [name_in_snake_case]

For example, to create a “prepare data” simulation, run:

$ e2e new simulation prepare_data

When running the above command, the sample code is generated under e2e_ext/simulations/prepare_data.py. Your task is now filling in the code needed in this file.

Another cool thing is that the type hints in e2e_ext/_typing.py is also automatically updated. This helps facilitate the autocompletion of the code editor.