Pattern: Use of quotes for right side of =~
Issue: -
Quotes on the right hand side of =~ can be used to match literally, so that [[ $1 =~ ^"$2".* ]] works even if $2 contains regex meta-characters. This mirrors the behavior of globs, [[ $1 = "$2"* ]].
This also means that the problematic code tries to match literal carets and plus signs instead of interpreting them as regular expression matchers. To match as a regex, the regex meta-characters it must be unquoted. Literal parts of the expression can be quoted with double or single quotes, or escaped.
Example of incorrect code:
[[ $foo =~ "^fo+ bar$" ]]Example of correct code:
[[ $foo =~ ^fo+\ bar$ ]]If you do want to match literally just to do a plain substring search, e.g. [[ $foo =~ "bar" ]], you could ignore this message, but consider using a more canonical glob match instead: [[ $foo = *"bar"* ]].