What should be done about Qt5.QtWidgets.QAction vs Qt6.QtGui.QAction?

What should be done about Qt5.QtWidgets.QAction vs Qt6.QtGui.QAction?

Ah, yeah, if so, then that's going to shout deprecation warnings at some users. I used PyQt6 for my list of widget names, so it didn't get converted. It looks like our code uses QtGui.QAction everywhere, so we're safe, otherwise.

We could whitelist QAction in the QtGui.__getattr__ we overwrite to not give a warning. Would any other strategy work better? Maybe we want to establish something like from .Qt.compatibility import QAction to make this all explicit? I don't know if that's easier for users to maintain, seeing as whatever documentation they're reading for Qt will only tell them to use one of the standard modules.

I'm glad this is being done, it's going to be painful to address the remaining open PRs, but it will be manageable.

I think we should take the opportunity to remove the unused imports; at the very least the ones in the examples, CodeQL looks to have registered 70ish new issues so hopefully that will cut down on that number a fair amount.

I was playing around on this branch; and ran into an issue. If we run isort on the entire repo; there are two problems.

1. pyqtgraph/util/colorama/win23.py - since this directory is just the sources of an old colorama release, I think we can exclude this directory from isort (probably should update it though, as it appears to be a pretty ancient version)
2. pyqtgraph/parametertree/__init__.py- this one is a bit more serious:

after isort runs on that file, it converts the file to the following contents:

# -*- coding: utf-8 -*-
from . import parameterTypes as types
from .Parameter import Parameter, registerParameterItemType, registerParameterType
from .ParameterItem import ParameterItem
from .ParameterSystem import ParameterSystem, SystemSolver
from .ParameterTree import ParameterTree

Unfortunately after the change, running pytest generates the following error:

ImportError while loading conftest '/Users/ogi/Developer/pyqtgraph/tests/conftest.py'.
tests/__init__.py:2: in <module>
    from .image_testing import assertImageApproved, TransposedImageItem
tests/image_testing.py:29: in <module>
    from pyqtgraph import GraphicsLayoutWidget, ImageItem, TextItem
pyqtgraph/__init__.py:259: in <module>
    from .widgets.ColorMapWidget import *
pyqtgraph/widgets/ColorMapWidget.py:7: in <module>
    from .. import parametertree as ptree
pyqtgraph/parametertree/__init__.py:2: in <module>
    from . import parameterTypes as types
pyqtgraph/parametertree/parameterTypes/__init__.py:3: in <module>
    from .action import ActionParameter, ActionParameterItem
pyqtgraph/parametertree/parameterTypes/action.py:6: in <module>
    class ActionParameterItem(ParameterItem):
E   TypeError: module() takes at most 2 arguments (3 given)

While we could mark the file for skip for isort purposes, we should probably try to resolve that issue whatever it may be.

After # isort:skip -ing the problematic line in parametertree/__init__.py, and re-running I sort, the test suite runs, but unfortunately we get some errors.

=================================================================== short test summary info ===================================================================
FAILED examples/test_examples.py::testExamples[ dockarea.py - PyQt5 ]
FAILED examples/test_examples.py::testExamples[ parametertree.py - PyQt5 ]
FAILED tests/dockarea/test_dockarea.py::test_dockarea - AttributeError: type object 'Dock' has no attribute 'Dock'
FAILED examples/test_examples.py::testExamples[ PlotSpeedTest.py - PyQt5 ]

More specifically:

  File "/Users/ogi/Developer/pyqtgraph/pyqtgraph/dockarea/Container.py", line 250, in _insertItem
    if not isinstance(item, Dock.Dock):
AttributeError: type object 'Dock' has no attribute 'Dock'

  File "/Users/ogi/Developer/pyqtgraph/pyqtgraph/parametertree/parameterTypes/pen.py", line 11, in __init__
    self.pdialog = PenSelectorDialog(fn.mkPen(param.pen))
  File "/Users/ogi/Developer/pyqtgraph/pyqtgraph/widgets/PenSelectorDialog.py", line 61, in __init__
    self.tree = ParameterTree(showHeader=False)
TypeError: 'module' object is not callable

I suspect it has to do with some confusion between objects and modules judging by the errors.

In pyqtgraph/parametertree/parameterTypes/actions.py, I think you need to change:

from .. import ParameterItem, Parameter

to

from ..ParameterItem import ParameterItem
from ..Parameter import Parameter

The former relies on pyqtgraph/parametertree/__init__.py having imported ParameterItem and Parameter into the namespace. Hence the breakage with isort.
Similar changes would need to be made to the other files within pyqtgraph/parametertree/parameterTypes/.

While browsing through that directory, I noticed that the following files were doing absolute instead of relative imports:

1. bool.py
2. str.py

from pyqtgraph.Qt import QtWidgets
from pyqtgraph.parametertree.parameterTypes import WidgetParameterItem

In pyqtgraph/parametertree/parameterTypes/actions.py, I think you need to change:

from .. import ParameterItem, Parameter

to

from ..ParameterItem import ParameterItem
from ..Parameter import Parameter

The former relies on pyqtgraph/parametertree/__init__.py having imported ParameterItem and Parameter into the namespace. Hence the breakage with isort. Similar changes would need to be made to the other files within pyqtgraph/parametertree/parameterTypes/.

While browsing through that directory, I noticed that the following files were doing absolute instead of relative imports:

1. bool.py
2. str.py

from pyqtgraph.Qt import QtWidgets
from pyqtgraph.parametertree.parameterTypes import WidgetParameterItem

Nice catch (on both the non-relative imports and the import of Parameter and ParameterItem)! That indeed fixed the issue w/ ParameterItems; still have the issue with Dock but I'm willing to bet it's something very similar.

EDIT: dock related error was even simpler to resolve... now that isort doesn't appear to cause breakages, moving onto pycln

EDIT 2: scratch that, some examples are failing.

EDIT 3: Fixed, just needed to update the import for PenSelectorDialog.py

I got isort and pycln to run over the entire repo, test suite runs and passes, but still getting lots of warnings such as:

 DeprecationWarning: Accessing QtWidgets through QtGui is deprecated and will be removed after Jan 2022. Use QtWidgets.QPushButton instead.

@outofculture do you know of a good way we can detect these uses in an automated fashion?

Was hoping to make more progress on this today; hopefully i'll make more of a go at it later tonight, the following are items available in PyQt5.QtWidgets but are not available in PyQt6.QtWidgets

QAction
QActionGroup
QDesktopWidget
QDirModel
QFileSystemModel
QKeyEventTransition
QMacCocoaViewContainer
QMouseEventTransition
QOpenGLWidget
QShortcut
QUndoCommand
QUndoGroup
QUndoStack

I found no items in PyQt6.QtWidgets that were not in PyQt5.QtWidgets

Will check out QtGui next for a more exhaustive listing.

Thanks @outofculture ! LGTM!