Pytest gets stuck when testing app with dynamically mounting animated widgets on timer

[Zaloog]

When testing my app with pytest, the test doesnt continue at a certain point.

Testfile: https://github.com/Zaloog/idle-tui-adventures/blob/main/tests/test_app.py

My initial guess was an issue with 2 intervalls running at the same in my app.
But after some debugging, its just the one timer, that makes the test stop.

My assumption is, that it has to do with the mounting of the damage widgets, which are Labels initialized with this method called:

    def fly_away(self):
        self.styles.animate(
            attribute="opacity",
            value=0,
            duration=1.5,
        )

        self.animate(
            attribute="offset",
            value=Offset(self.parent_center[0] + self.wiggle, 0),
            duration=1.0,
            on_complete=self.remove,
            easing="out_expo",
        )

Here is a short clip to show what that looks like:
https://github.com/user-attachments/assets/08c72ad2-36c2-4018-97f2-c794d2aadbbf

Textual Diagnostics

Versions

Name	Value
Textual	0.76.0
Rich	13.7.1

Python

Name	Value
Version	3.12.2
Implementation	CPython
Compiler	MSC v.1929 64 bit (AMD64)
Executable	C:\Users\grams\rye_projects\idle-tui-adventures.venv\Scripts\python.exe

Operating System

Name	Value
System	Windows
Release	11
Version	10.0.22631

Terminal

Name	Value
Terminal Application	Windows Terminal
TERM	Not set
COLORTERM	Not set
FORCE_COLOR	Not set
NO_COLOR	Not set

Rich Console options

Name	Value
size	width=141, height=55
legacy_windows	False
min_width	1
max_width	141
is_terminal	True
encoding	utf-8
max_height	55
justify	None
overflow	None
no_wrap	False
highlight	None
markup	None
height	None

PyTest Setup:

• platform win32 -- Python 3.12.2, pytest-8.3.2, pluggy-1.5.0
• plugins: asyncio-0.23.8, cov-5.0.0, xdist-3.6.1

[github-actions]

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• How do I center a widget in a screen?
• Why doesn't Textual look good on macOS?
• Does Textual support images?

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This is an automated reply, generated by FAQtory

[willmcgugan]

Are you doing a lot of animation? The test system will wait for animation to complete after keys / clicks etc. This is so the snapshot can be taken at a point where the state is knowable. But it does mean that if you are always animating, it will never return!

[Zaloog]

Currently around every second, but its dependend on an attack_speed variable, so in the application itself it might be faster.
But if I define like a test_character with attack_speed of e.g. 0.5 -> animation appear interval would be 2s and the longer animation itself takes 1.5 s, so the animation can complete, before a new one appears.

Edit:
Nvm, quickly tested it, jep that fixes it.
So I guess for testing lower the animation speed, i.e. attack speed

Thanks @willmcgugan

[Zaloog]

ill close this then

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