Rubocop: Style/RedundantRegexpCharacterClass unintentional changes in specific case

[renyamizuno]

Style/RedundantRegexpCharacterClass is problematic under in specific case:

def escape(text)
  text.gsub(/.[\b]/, '')
end

# Style/RedundantRegexpCharacterClass: Redundant single-element character class, [\b] can be replaced with \b..

but, \b [\b] behave differently.

https://docs.ruby-lang.org/en/2.7.0/Regexp.html#class-Regexp-label-Anchors

\b - Matches word boundaries when outside brackets; backspace (0x08) when inside brackets

---

Expected behavior

Ignore [\b] case.

Actual behavior

Change [\b] to \b.

RuboCop version

$ [bundle exec] rubocop -V
0.86.0 (using Parser 2.7.1.4, rubocop-ast 0.0.3, running on ruby 2.7.1 x86_64-darwin18)

[bbatsov]

@owst Can you take a look?

[owst]

Aha, I missed this difference in behaviour, apologies - I'll have a look this evening UK time 👍

[renyamizuno]

thx!