[Question]How do I write test code using pytest?

[NaotoTakata]

Question

Hi flet community

I would like to ask how to write test code for a Flet application using pytest.
I did a quick search, but there's not a lot of information about it.

Let's say my application is as follows:

I want to make sure that self.message.value is "Water" when you run the app, and after clicking self.btn, self.message.value should be "Coffee."

Code sample

import flet as ft


class SubClass(ft.UserControl):
    def __init__(self, page: ft.Page):
        super().__init__()
        self.page = page
        self.message = ft.Text("Water")

        self.btn = ft.ElevatedButton(text="change to Coffee", on_click=self.clicked_btn)

    def clicked_btn(self, e):
        if self.message.value == "Coffee":
            self.message.value = "Water"
            self.btn.text = "change to Coffee"
        else:
            self.message.value = "Coffee"
            self.btn.text = "change to Water"

        self.message.update()
        self.btn.update()

    def build(self):
        return ft.Column(controls=[self.message, self.btn])


def main(page: ft.Page):
    subclass = SubClass(page)
    page.add(subclass)
    page.update()


if __name__ == "__main__":
    ft.app(target=main)

Error message

No response

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• I have searched for answers to my question both in the issues and in previous discussions.

[dstalzjohn]

I am confronted with the same problem and didn’t find a solution. What doesn’t work is the use of playwright or something similar because they work with frameworks based on node.js.

[DanMarqz]

Hello,

I don't know if pytest can be used to perform tests in Flet, however, in the CONTRIBUTING.md file there is a section that talks about how to perform tests on the fork created to contribute, I leave the document here so you can view it.

Greetings.

[dstalzjohn]

Thank you for your comment. Unfortunately, I only found tests written in dart. What we need is testability of our application written in flet using pytests.

The only possibility I currently see here are screenshot tests which would mean a lot of overhead.