Fixing ZeroDivisionError thrown by UI sliders when the value_range is zero (0)

[ganimtron-10]

Currently, the UI sliders throw ZeroDivisionError whenever the value_range is zero ie. min_value and max_value are the same.
Adding checks to avoid these errors and setting the handle at the start.

[codecov]

Codecov Report

Merging #645 (b5835d0) into master (bca7b33) will decrease coverage by 1.02%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master     #645      +/-   ##
==========================================
- Coverage   52.04%   51.02%   -1.03%     
==========================================
  Files         108      108              
  Lines       23812    23894      +82     
  Branches     2631     2631              
==========================================
- Hits        12394    12192     -202     
- Misses      11013    11293     +280     
- Partials      405      409       +4     

Impacted Files	Coverage Δ
fury/ui/elements.py	0.00% <0.00%> (ø)
fury/ui/tests/test_containers.py	0.00% <0.00%> (ø)
fury/ui/tests/test_elements.py	0.00% <0.00%> (ø)
fury/fury/tests/test_window.py	50.94% <0.00%> (-35.43%)	⬇️
fury/fury/ui/tests/test_containers.py	64.76% <0.00%> (-28.96%)	⬇️
fury/fury/window.py	72.85% <0.00%> (-10.41%)	⬇️
fury/fury/shaders/base.py	84.84% <0.00%> (-8.09%)	⬇️
fury/fury/ui/containers.py	82.92% <0.00%> (-0.89%)	⬇️
fury/fury/data/fetcher.py	67.81% <0.00%> (-0.43%)	⬇️
fury/fury/actor.py	88.87% <0.00%> (-0.19%)	⬇️
... and 6 more

[m-agour]

Hello @ganimtron-10,
Thanks for making this PR, it's really important. Also, thanks for adding the unit test.

[xtanion]

Hi @ganimtron-10, I tried this with this animation example and the Fox model. It was causing ZeroDivisionError previously. It's working fine now 👍🏽.

I still need to check this with different models, I'll let you know if I find anything.

[skoudoro]

hi @ganimtron-10,

The fix looks good to me. however, the tests are weird.... Can you update your tests? thanks

[m-agour]

Hi @ganimtron-10 ,
Thank you for updating the tests. Can you also test for other range cases such as the following for each slider?

    with npt.assert_no_warnings():
        line_slider = ui.LineSlider2D(min_value=0, max_value=0,
                                      center=(200, 450))

        assert_equal(line_slider.value, 0)
        assert_equal(line_slider.min_value, 0)
        assert_equal(line_slider.max_value, 0)
        line_slider.value = 100
        assert_equal(line_slider.value, 0)
        line_slider.value = -100
        assert_equal(line_slider.value, 0)

        line_slider = ui.LineSlider2D(min_value=0, max_value=100,
                                      center=(200, 450))
        line_slider.value = 105
        assert_equal(line_slider.value, 100)
        line_slider.value = -100
        assert_equal(line_slider.value, 0)

[ganimtron-10]

Thank You @m-agour for the suggestion.
I have updated the tests!
PTAL.
Thanks!

[skoudoro]

LGTM, thanks @ganimtron-10 and @m-agour ! merging