These methods aren't part of the public API, and were removed in ESLint v3.17.0. (Using them for now is probably fine, but they'll need to be changed to sourceCode.getLocFromIndex and sourceCode.getIndexFromLoc when ESLint is upgraded.)

Yes, I know.

FWIW I've added a check to support the later versions too.

Would we want to report the node when i + 1 === str.length? This would cover the case where the . is at the end of the regex, e.g.

assert.throws(func, /this error message ends with a dot./);

Changed.

This could cause some weird behavior if the argument to RegExp isn't just string concatenation:

// 'foo.bar' gets interpreted as a regex pattern
new RegExp(function() {
  return crypto.createHash('sha1').update('foo.bar').digest('hex');
}());

Or it could handle character classes incorrectly:

const closingBracket = ']';

new RegExp('[abc' + closingBracket + '.');

There's no perfect solution to this, so it's probably fine as-is if we're not running into cases like this.

Regarding the first example, I originally had it coded differently and actually checked parent nodes when encountering string literals, but that seemed more complicated.

Regarding the second example, I pointed that out in the PR description. I doubt that would ever become a problem in practice though.

I've re-added the strict parent node checking.