False positive in Style/RedundantRegexpEscape

[jfeltesse-mdsol]

I believe #11152 introduced a false positive.

---

Expected behavior

Given the regex

%r{  remote: (?:git@|git://|https://)(?<domain>[^/]+)[/:](?<slug>[\w\-._]+/[\w\-._]+)}

rubocop shouldn't complain about the redundancy of slashes in the <slug> capture, as removing them leads to a syntax error:

unmatched range specifier in char-class: /  remote: (?:git@|git:\/\/|https:\/\/)(?<domain>[^\/]+)[\/:](?<slug>[\w-._]+\/[\w-._]+)/

Actual behavior

C: [Correctable] Style/RedundantRegexpEscape: Redundant escape inside regexp literal
      GIT_URI_REGEX = %r{  remote: (?:git@|git://|https://)(?<domain>[^/]+)[/:](?<slug>[\w\-._]+/[\w\-._]+)}
                                                                                          ^^

C: [Correctable] Style/RedundantRegexpEscape: Redundant escape inside regexp literal
      GIT_URI_REGEX = %r{  remote: (?:git@|git://|https://)(?<domain>[^/]+)[/:](?<slug>[\w\-._]+/[\w\-._]+)}
                                                                                                    ^^

Steps to reproduce the problem

1. use rubocop 1.39.0 with above regex
2. above offenses are reported
3. use rubocop 1.38.0
4. no offenses

RuboCop version

rubocop -V
1.39.0 (using Parser 3.1.2.1, rubocop-ast 1.23.0, running on ruby 3.1.2) [arm64-darwin21]
  - rubocop-performance 1.15.0
  - rubocop-rspec 2.15.0

[olliebennett]

I boiled the provided REGEX down to some simpler examples;

• %r{[\w\-x]} becomes %r{[\w-x]} which causes "unmatched range specifier in char-class" SyntaxError
• %r{[x\-\w]} becomes %r{[x-\w]} which causes "char-class value at end of range" SyntaxError

The same applies when replacing \w with any of the character classes;

• \s | Any whitespace character
• \S | Any non-whitespace character
• \d | Any digit
• \D | Any non-digit
• \w | Any word character (letter, number, underscore)
• \W | Any non-word character
• ... maybe other niche ones I'm not aware of?

Hope that helps when someone is able to write a spec and fix it 🤞 🙏