Add UnnecessaryFilter rule

[VovaStelmashchuk]

Issue: #3340

[VovaStelmashchuk]

I don't have idea about implementation at the moment.

[codecov]

Codecov Report

Merging #3341 (89f248b) into master (731a2db) will decrease coverage by 0.01%.
The diff coverage is 79.41%.

@@             Coverage Diff              @@
##             master    #3341      +/-   ##
============================================
- Coverage     80.38%   80.37%   -0.02%     
- Complexity     2748     2763      +15     
============================================
  Files           449      450       +1     
  Lines          8300     8335      +35     
  Branches       1587     1599      +12     
============================================
+ Hits           6672     6699      +27     
  Misses          774      774              
- Partials        854      862       +8     

Impacted Files	Coverage Δ	Complexity Δ
...arturbosch/detekt/rules/style/UnnecessaryFilter.kt	78.78% <78.78%> (ø)	14.00 <14.00> (?)
...rturbosch/detekt/rules/style/StyleGuideProvider.kt	100.00% <100.00%> (ø)	3.00 <0.00> (ø)
...ain/kotlin/io/github/detekt/metrics/LinesOfCode.kt	92.30% <0.00%> (-0.80%)	0.00% <0.00%> (ø%)
...gitlab/arturbosch/detekt/cli/runners/AstPrinter.kt	100.00% <0.00%> (ø)	4.00% <0.00%> (ø%)
...rturbosch/detekt/rules/bugs/UnnecessarySafeCall.kt	75.00% <0.00%> (ø)	5.00% <0.00%> (+1.00%)
...turbosch/detekt/rules/style/UnusedPrivateMember.kt	90.76% <0.00%> (+0.14%)	5.00% <0.00%> (ø%)

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[VovaStelmashchuk]

Implementation ready. Can someone review my changes?

[VovaStelmashchuk]

I see codecov report. I can add some test for increase test coverage. But i cannot see reason for add test only for increase test coverage. The additional test will not add real benefits.

[cortinico]

I see codecov report. I can add some test for increase test coverage. But i cannot see reason for add test only for increase test coverage. The additional test will not add real benefits.

You're fine like that 👍 Codecov coverage report is not a hard requirement for merging. In this case you're at 76.00% of your patch that is totally fine

[chao2zhang]

Thank you so much for the contribution and for being patient in the back-and-forth requested changes.

[chao2zhang]

For other maintainers in this PR (@cortinico @BraisGabin @schalkms): We entered 1.16-RC but is it reasonable to add new rules with active = false by default?
I can think of arguments for both sides:

• We want to only allow bug fixes in RC to speed up the full release
• We want people to try out experimental new rules early so we can enable them by default faster

[cortinico]

• We want to only allow bug fixes in RC to speed up the full release
• We want people to try out experimental new rules early so we can enable them by default faster

Historically we've been pretty slow at enabling rules by default so I don't mind adding a disabled rule in a RC. Also if we have rules that are ready to go, like this one or #3413, I'll try to squeeze them into 1.16.0 to let them reach our users sooner (so we can get a faster feedback loop).

That being said, I'm in for merging this

[BraisGabin]

! The RC are more to make sure that some changes in the core or clients doesn't break. We did add rules between RC previusly.

The review is on an out-dated diff and is addressed later.