Implement #139

[mottosso]

This introduces a radical change to counter #139, #109, #112 and #96.

The change involves moving all added members of Qt.py to it's own individual module, QtShim.

# Before
import Qt
Qt.setSectionResizeMode()
Qt.__binding__

# After
from Qt import QtShim
QtShim.setSectionResizeMode()
QtShim.__binding__ == "PyQt5"

• See Example

It also counteracts our current Achilles heel, which is that at some point one of our additions are bound to conflict with native existing members of the binding. For example, if one day PySide decides to add __qt_version__ to their offering, but have a different type for it, like tuple, whereas we have str

So I'm on the fence about whether this is the right way to do it. The disadvantage is a more complex code base; the reader must now understand how self plays a part, and how QtShim even makes it into the Qt namespace.

So let me know what you think.

[fredrikaverpil]

This only applies to members we've added ourselves, right? (so for instance, QtWidgets is not changed but e.g. load_ui is moved?

Could we just make a list of them here before merging, for completeness?
I'm wondering if QtShim is the best name though.

[mottosso]

This only applies to members we've added ourselves, right? (so for instance, QtWidgets is not changed but e.g. load_ui is moved?

Yeah.

Remap as per usual, and make our own space for our own members.

Could we just make a list of them here before merging, for completeness?

Of course, list is in the README.

I'm wondering if QtShim is the best name though.

The name is up for grabs. QtShim is bad because it has no obvious connection to Qt.py. I wanted to name it Qt.py, but of course couldn't. QtCompat was another option that crossed my mind, but wasn't sure since load_ui isn't necessarily a compatibility function. Got anything in mind?

Edit: Not to mention __binding__ and similar.

[fredrikaverpil]

Of course, list is in the README.

Ah, excellent. Makes it easier to come up with a good name for this.

Hm. How about something like

from Qt import Custom

I mean.. what are the chances that... hm. I'll have to sleep on it.

[mottosso]

How was your sleep? :)

How about..?

# After
from Qt import QtCompat
QtCompat.setSectionResizeMode()
QtCompat.__binding__ == "PyQt5"

I think we'll need the Qt-prefix on whichever name we choose, to make it blend better with other calls. In the middle of a block of code, it can be difficult to tell where Custom or something else without this prefix comes from.

button = QtWidgets.QPushButton("Button")
Custom.someOtherFunction()  # Is this related to Qt?

[fredrikaverpil]

from Qt import QtCompat

Yep. Sounds good. Let's go for it.

Does this backwards-breaking feature mean that we should also scramble for a v1.0.0 release?

[mottosso]

It doesn't break backwards compatibility, the current members still work. Once we hit 1.0, we can remove them.

See the _maintain_backwards_compatibility function at the bottom.

[fredrikaverpil]

See the _maintain_backwards_compatibility function at the bottom.

Ah, that's perfect.

Once we hit 1.0, we can remove them.

Sounds good!

This all looks excellent to me.