Short answer:
Use a string generator that is much more likely to have collisions, and
thus provoke your failure. Here's an example:
(def small-strings (gen/sized (fn [s] (gen/resize (min s 2) (gen/not-empty
gen/string-ascii)
Longer answer:
When using gen/bind, you create a nested shrink t
My thought process with that suggestion is that a shrink of the matrix elements
(not the size), will not require the samples and probes to be regenerated.
At some point I'll probably have to look into how the shrinking works.
> On 13 Nov 2014, at 06:18, Brian Craft wrote:
>
> I tried your idea
I tried your idea of generating the size first, then passing it to the
matrix & vector generators. This does seem to work better. The shrunk cases
that return are actually worse, but so far it hasn't wedged itself, which
is a great improvement. They all return within a few seconds. I don't yet
I'm pretty sure I did encounter the performance problem you're talking about,
but I killed it and re-ran until I hit cases that shrink quickly. I'm afraid
I'm not much help with those, although I agree that the bad shrinking is
probably related to the performance issues.
> On 13 Nov 2014, at 04
Interesting that you don't see a performance problem. What version did you
try? I'm using 0.5.9.
I just re-ran this example to make sure I wasn't imagining it. On the 11th
run, it wedged, not returning, and burning a lot of cpu, presumably trying
to shrink.
It's a larger problem with the real
I've also had some tricky shrinking type issues with recursive generators using
bind. I had a play with your generators, using such-that to reduce the
row/column name length and also preventing some generator shrinking by using
no-shrink, but I didn't have much luck improving the resulting shrin
Using test.check, I'm finding the shrinking to be very, very slow. Running
a hundred cases takes a few seconds, unless it hits an error, in which case
it takes 40-60 minutes to shrink, and the shrinking is not very effective
(resulting test case is much larger than necessary). Sometimes the
shr
