UnderscoresInNumericLiterals: Allow numbers with non standard groupings

[marschwar]

fixes #4276

I am somewhat unsure how to handle this. In my opinion this rule should have never reported a violation for groups other than three but changing this now will is a breaking change.

[codecov]

Codecov Report

Merging #4280 (9cc086a) into main (c6f796a) will decrease coverage by 0.02%.
The diff coverage is 100.00%.

❗ Current head 9cc086a differs from pull request most recent head c8c9f65. Consider uploading reports for the commit c8c9f65 to get more accurate results

@@             Coverage Diff              @@
##               main    #4280      +/-   ##
============================================
- Coverage     84.27%   84.24%   -0.03%     
- Complexity     3249     3263      +14     
============================================
  Files           471      472       +1     
  Lines         10261    10315      +54     
  Branches       1805     1821      +16     
============================================
+ Hits           8647     8690      +43     
- Misses          664      666       +2     
- Partials        950      959       +9     

Impacted Files	Coverage Δ
...detekt/rules/style/UnderscoresInNumericLiterals.kt	87.23% <100.00%> (+4.30%)	⬆️
...ch/detekt/core/suppressors/AnnotationSuppressor.kt	80.76% <0.00%> (-9.24%)	⬇️
...osch/detekt/rules/coroutines/CoroutinesProvider.kt	100.00% <0.00%> (ø)
.../arturbosch/detekt/core/suppressors/Suppressors.kt
...b/arturbosch/detekt/core/suppressors/Suppressor.kt	69.23% <0.00%> (ø)
...rbosch/detekt/rules/coroutines/InjectDispatcher.kt	81.81% <0.00%> (ø)

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[BraisGabin]

What do you think about adding a flag forceGroupsOfThree (we need a better name) that forces the old behaviour? Disabled the rule will allow any type of _. And I think that it should be enabled by default.

[scottkennedy]

I like that, as it keeps the default behavior the same.

[marschwar]

I don't love it but for backward compatibility this is most likely our best choice.

[BraisGabin]

What does the elvis operator here?

[marschwar]

This only marks a non-capture group. I could remove it, if it is confusing.

If you do not need the group to capture its match, you can optimize this regular expression into Set(?:Value)?. The question mark and the colon after the opening parenthesis are the syntax that creates a non-capturing group.

https://www.regular-expressions.info/brackets.html

[BraisGabin]

I think that keeping the regex as simple as possible is better (if it doesn't affects the performance). But to be honest my comment was pure curiosity.