[pytest-dev] [3.1 feature] "assert not raise exception" helper: opinions about the name

[holger krekel]

On Tue, Apr 04, 2017 at 15:48 +0000, Bruno Oliveira wrote:
> On Fri, Mar 31, 2017 at 8:24 AM Bruno Oliveira <nicoddemus at gmail.com> wrote:
> 
> > Hi all,
> >
> > On Fri, Mar 31, 2017 at 7:13 AM Vasily Kuznetsov <kvas.it at gmail.com>
> > wrote:
> >
> > Hi Holger and Ronny,
> >
> > I see merit in both of your points. All those "is not None" checks in
> > between other logic and the proposed "raises unless the argument is None"
> > semantics of pytest.raises do increase complexity (I'm not qualified to
> > predict whether or not this increase is significant in terms of further
> > maintenance though) but at the same time "pytest.raises(None)" API is
> > convenient in some cases. What if we do something like this:
> >
> > ...
> >
> > The "is not None" checks are gone from the main logic and both APIs are
> > available. Or if we would rather not have more than one way to do it, we
> > can drop "does_not_raise" but otherwise still keep it a separate context.
> >
> > Seems like if we can agree on the API, a not-complexity-increasing option
> > of implementation is possible.
> >
> >
> > Now for the specific case of pytest.raises(None), I believe we can strike
> > a good balance between a nice user interface and minimal internal impact
> > like Vasily proposes, unless Ronny or others feel that pytest.raises(None)
> > is not a good interface for this functionality.
> >
> 
> Guys, anything else to add here? I would like to move the implementation
> forward, either in its current form or changing it to pytest.raises(None).

i was and am fine with your suggestion!

IMO compared to markers or fixtures ... "pytest.raises" is relatively 
self-contained side-effect-free code so i don't think it's neccessary
to get scared about maintanability too much in this case.

cheers, holger

> 
> Ronny, after the discussion here are you still against using
> ptyest.raises(None), given that we can implement it easily by Vasily's
> suggested implementation?
> 
> Cheers,
> Bruno.