- The app's directory structure is not a constant, and shouldn't play into this test. Aside from codebase restructuring, directories like `__pycache__` can come and go.
- Even if a temporary directory were created with files enough to fill the view, the scrollbar would still change based on the folder structure outside of the temporary folder.
- pyfakefs is one way to ensure a consistent view of a folder structure for testing. It allows adding real folders in a readonly way. It's more complicated than I thought it would be going in, since I had to add workarounds for pyfiglet and pytest-textual-snapshot, and handle an edge case in my EnhancedDirectoryTree (which got an error which seems to be swallowed?), not to mention pyfakefs raises an error saying "No such file or directory in the fake filesystem" when actually it's the real directory not existing when trying to add it to the fake filesystem, and VS Code was hiding stack frames and refusing to step into library code, and it turned out that I was resolving the absolute path wrong, but it looked right to me because the only part that was missing was "textual-paint", when, at a glance it seemed present, since the "textual_paint" part was present. Ay-ay-ay!
- I don't know if this will fix the problem I saw where these tests' snapshots all changed with no visual or even structural changes, just the IDs of elements changing. I don't know what caused that.
Oh yeah and this is still actually a problem:
============================================= short test summary info ==============================================
FAILED tests/test_snapshots.py::test_paint_open_dialog[light_unicode] - AttributeError: 'EnhancedDirectoryTree' object has no attribute '_id'. Did you mean: 'id'?
FAILED tests/test_snapshots.py::test_paint_open_dialog[dark_unicode] - AttributeError: 'EnhancedDirectoryTree' object has no attribute '_id'. Did you mean: 'id'?
FAILED tests/test_snapshots.py::test_paint_open_dialog[light_ascii] - AttributeError: 'EnhancedDirectoryTree' object has no attribute '_id'. Did you mean: 'id'?
FAILED tests/test_snapshots.py::test_paint_open_dialog[dark_ascii] - AttributeError: 'EnhancedDirectoryTree' object has no attribute '_id'. Did you mean: 'id'?
FAILED tests/test_snapshots.py::test_paint_save_dialog[light_unicode] - AttributeError: 'EnhancedDirectoryTree' object has no attribute '_id'. Did you mean: 'id'?
FAILED tests/test_snapshots.py::test_paint_save_dialog[dark_unicode] - AttributeError: 'EnhancedDirectoryTree' object has no attribute '_id'. Did you mean: 'id'?
FAILED tests/test_snapshots.py::test_paint_save_dialog[light_ascii] - AttributeError: 'EnhancedDirectoryTree' object has no attribute '_id'. Did you mean: 'id'?
FAILED tests/test_snapshots.py::test_paint_save_dialog[dark_ascii] - AttributeError: 'EnhancedDirectoryTree' object has no attribute '_id'. Did you mean: 'id'?
========================== 8 failed, 56 passed, 1 xfailed, 1 warning in 152.86s (0:02:32) ==========================
It worked when running in debug, but not when running normally.
- Fix `APP_PATH` reference error
- Hold Ctrl to set the foreground color (modifiers not recorded yet)
- DRY `pilot.press`
- Use same terminal size as many other tests
- Seven isn't spelt with a 2, but zero is! ;)
This was kind of mind-boggling, narrowing it down to dark mode,
and then to dark mode *but not CSS*.
I kept narrowing it down, and looked into how dark mode was implemented,
and finally figured this out.
`app.call_later(app.refresh_css)` in `App.watch_dark` causes a timing issue.
I'm basically doing TDD to snapshot testing!
I'm creating tests that don't pass yet, setting up an expectation
that the app match the given screenshots, which is funny in a nice
"improper hierarchy" sort of way, but it's possible because I do
actually have the app rendering how I want, just only in isolation.
If I run the ascii_only tests by themselves, I can get good results
from them, but running them interwoven with default Unicode-using UI
tests doesn't work yet, since the ASCII-only mode permanently changes
how certain widgets render, for the life of the process, so that's
what I'm applying TDD to: making it toggleable at runtime.
I commented out the Unicode tests, and uncommented the ASCII-only tests,
renamed test_snapshots.ambr to test_snapshots_ascii.ambr,
reverted the changes to test_snapshots.ambr to get the Unicode version,
ran my new merge_ambr.py script to join the sets of snapshots,
then replaced test_snapshots.ambr with test_snapshots_merged.ambr
Finally, I uncommented both sets of tests, and I'm ready to do TDD!
First I tried setting PYTEST_TEXTUAL_PAINT_ARGS as an environment variable, to be interpreted by args.py, but it turns out args.py is only executed once, not once per test. It's not using subprocesses, only importing and reimporting the app code, and instantiating new App instances, so parts of the code that are at the top level of modules is only evaluated once.
So I found a new strategy, of importing the `args` object in the test fixture and modifying it directly.
I also realized the --ascii-only option permanently modifies Textual's widgets and borders, and my own widgets, for the life of the process, so I'm holding off on that one. I should be able to make --ascii-only mode more dynamic, and could even target it as a runtime toggle, as a goal, since that's basically what I'll need to achieve to get it working for the tests, but thinking of it as a feature is more fun.
