Fix 1275: Make MaxValueValidator default an integer

[wearebasti]

This should fix the issue #1275 by making the default value an integer and providing the option to set the max value per filter instance

[codecov-commenter]

Codecov Report

Merging #1276 into master will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #1276   +/-   ##
=======================================
  Coverage   99.44%   99.44%           
=======================================
  Files          15       15           
  Lines        1265     1265           
=======================================
  Hits         1258     1258           
  Misses          7        7           

Impacted Files	Coverage Δ
django_filters/filters.py	100.00% <100.00%> (ø)

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[carltongibson]

Hi.

I deliberately don't want to add a kwarg. It complicates the interface for all users, only 1 in a million of which will ever need to change it. Create a subclass if that's you. (Such would need docs and tests.)

Can you add a test case showing the problem case this change would resolve? (Thinking through trapping the signal there...)

Cheers.

[wearebasti]

Hi, thanks for the input!

I deliberately don't want to add a kwarg. It complicates the interface for all users, only 1 in a million of which will ever need to change it. Create a subclass if that's you. (Such would need docs and tests.)

Removed the kwarg again, just thought it might come in handy for some people - no feelings in either way from my side.

Can you add a test case showing the problem case this change would resolve? (Thinking through trapping the signal there...)

I added a test-case that activates the Decimal Trap first. The idea is to avoid some - for the user - strange side-effects of float/Decimal/int-comparisons (https://docs.python.org/3/library/decimal.html#floating-point-notes).

Does this make sense for you?

[carltongibson]

Super. Thanks for the update. Let me have a play, but looks good.

[carltongibson]

I just want to have a look at the order of validation in the field, but maybe this should be a decimal already...
(i.e. did we already run the value from the widget through to_python, giving us a decimal in the value < limit check...)