About using/notusing 'assert' in the code

[dpizetta]

@goanpeca what is your opinion about these messages and orientations?

From here: https://travis-ci.org/github/ColinDuquesnoy/QDarkStyleSheet/jobs/664411481?utm_medium=notification&utm_source=github_status

Explanation here: https://bandit.readthedocs.io/en/latest/plugins/b101_assert_used.html

Also, the var file_colors are defined internally to the loop.

Run started:2020-03-19 14:19:11.618937
Test results:
>> Issue: [B101:assert_used] Use of assert detected. The enclosed code will be removed when compiling to optimised byte code.
   Severity: Low   Confidence: High
   Location: qdarkstyle/utils/images.py:69
   More Info: https://bandit.readthedocs.io/en/latest/plugins/b101_assert_used.html
68	
69	    assert file_colors
70	
71	    return file_colors
--------------------------------------------------
Code scanned:
	Total lines of code: 11852
	Total lines skipped (#nosec): 0
Run metrics:
	Total issues (by severity):
		Undefined: 0.0
		Low: 1.0
		Medium: 0.0
		High: 0.0
	Total issues (by confidence):
		Undefined: 0.0
		Low: 0.0
		Medium: 0.0
		High: 1.0
Files skipped (0):
ERROR: InvocationError for command /home/travis/build/ColinDuquesnoy/QDarkStyleSheet/.tox/py38-safety/bin/bandit --recursive qdarkstyle (exited with code 1)
___________________________________ summary ____________________________________
ERROR:   py38-safety: commands failed
The command "tox" exited with 1.

[goanpeca]

@dpizetta yes indeed we should not use asserts for these things as they are removed when compiling optimized code. So we should use proper checks and raise exceptions as needed if something is not complying with these checks.

[dpizetta]

Could you make those changes? TKs