On Tue, Nov 1, 2011 at 5:29 PM, Anton Gyllenberg <an...@iki.fi> wrote:
> On Tue, Nov 1, 2011 at 20:48, Glyph <gl...@twistedmatrix.com> wrote: > > On Nov 1, 2011, at 12:14 PM, Phil Mayers wrote: > >> I find the "pass reactor as 1st argument to everything" API pattern > >> messy. I'm sure there's a good reason. What is it? > > > > This pattern is a solution to the problem, but I agree that it is > possibly not the optimal solution. It sort of points in a direction where > every possible module that might be imported becomes an argument to your > function. After all, there are plenty of other modules which have to be > mocked for testing, why not just make everyone's __init__ method take > sys.modules as an argument too, and never import anything? In more complex > systems this can definitely turn into a bit of a mess. > > I've often wondered whether there is a *real* use of the reactor > argument other than unit testing. I haven't had other uses for it, and > haven't seen (or perhaps not understood) real application code making > use of it. Now, I've sometimes made an argument for unit testing, > other than the obvious quality assurance, that unit tested code will > be more reusable and have better interfaces as it already is used for > at least two things: the real application and the unit test. However, > if accommodating unit testing requires sacrificing the natural > interface, then that kind of takes the edge off that argument. > > Thanks to everybody for the discussion and input. Very informative! > > Here's the thing: not only does removing the global reactor make *our* unit tests a lot nicer, it makes the unit tests of our users much easier to write, since they will want to use our APIs in their unit tests in a way that doesn't require ugly global hacking. I don't know how many times I have raged at some crappy library whose code is incompatible with consumer unit testing. Having testable interfaces is a really valuable feature we can provide to our users. -- Christopher Armstrong http://radix.twistedmatrix.com/ http://planet-if.com/
_______________________________________________ Twisted-Python mailing list Twisted-Python@twistedmatrix.com http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python
