no-useless-escape is too aggressive

Tell us about your environment

• ESLint Version: 3.10.2
• Node Version: 6.9.1
• npm Version: 3.10.8

What parser (default, Babel-ESLint, etc.) are you using? Default

Please show your full configuration: eslint-config-standard 6.2.1

Specifically:

{
  "no-useless-escape": 2
}

What did you do? Please include the actual source code causing the issue.

/Expected property "1" of type \[Buffer\], got String "foobar"/

What did you expect to happen?

No error about a useless escape.

What actually happened? Please include the actual, raw output from ESLint.

Unnecessary escape character: \]. (no-useless-escape)

[feross]

@not-an-aardvark That solution (making the rule configurable to ignore particular useless escapes) would work for standard. Then we could configure it to ignore ) and ].

I still feel that this ought to be the default, because this looks incorrect and unbalanced:

/\[brackets]/
/\(parens)/

But I’ll defer to you and the other contributors on this.

[not-an-aardvark]

) only needs to be escaped outside of character classes.

/)/; // syntax error

/\)/; // ok

/[)]/; // ok

/[\)]/; // useless escape