Simplify PEP8 method aliases in QtBot class.

[luziferius]

This commit simplifies the creation of PEP8 compliant method aliases.

It reduces call stack depth by one and enables better parameter suggestions in IDEs.

Before:

After:

Also added unit test verifying that each alias points to the correct source method.

(I hope that the test function location is OK)

[nicoddemus]

Thanks @luziferius for the PR!

However that way to declare the aliases was how it was done some time ago, until https://github.com/pytest-dev/pytest-qt/pull/326. Please take a look there to see the rationale and let us know what you think.

[luziferius]

Thanks @luziferius for the PR!

However that way to declare the aliases was how it was done some time ago, until #326. Please take a look there to see the rationale and let us know what you think.

Oops. Haven’t seen that. I just assumed it was a legacy implementation that was this way because of Python 2.x compatibility.

I’ll experiment with another solution then.

[luziferius]

I think I have found a solution.

Are you fine with a solution that breaks, if the subclass overwrites __init__() but does not perform a super() call in it’s own __init__() implementation?

I’d consider doing so an illegal use of the base class, so it should be fine from my point of view.

[nicoddemus]

Thanks!

I’d consider doing so an illegal use of the base class, so it should be fine from my point of view.

I agree, that would be fine.

[luziferius]

Done. The PEP 8 aliases are now only defined in __init__().

The unit tests added do:

• Both tests auto-discover PEP8 aliases, to make sure that aliases added in the future will be covered as well.
• Check that the alias point to the right method, i.e. that assignments are not shuffled around, like the faulty self.wait_active = self.waitSignal. This also prevents accidentally adding an independent method that just looks like a PEP8 alias.
• Check that the PEP8 alias points to the correct implementation when sub-classing QtBot. The test programmatically generates subclasses that overwrite a camelCaseMethod and verifies that the alias points to the overwritten method.

[nicoddemus]

Thanks @luziferius!

The PR and the solution is very well written, and the added checks are the cherry on the cake. Thanks! 🍰

My very (small) concern is that we are creating a reference cycle in QtBot.__init__, but I don't think it will really be an issue given QtBot is small in size.

[luziferius]

My very (small) concern is that we are creating a reference cycle in QtBot.__init__, but I don't think it will really be an issue given QtBot is small in size.

Would you mind to elaborate on this?

Do you mean something like this below or something entirely different?

self.a = self.b
self.b = self.a

[nicoddemus]

I mean:

self.add_widget = self.addWidget

Creates a circular reference because self.add_widget is a bound method to self.addWidget, which references self.