RegExp properties not applying when adding more than one annotation

[ibrahimEltayfe]

Hi, I'm encountering an issue when using multiple annotations when specifying multiLine or unicode or any other properties in the RegExp . I'm using the following regex patterns to detect hashtags and mentions in text:

final RegExp hashtagTextRegex = RegExp(
    r'#([\p{L}\p{N}_]+)',
    multiLine: true,
    unicode: true
);

final RegExp mentionTextRegex = RegExp(
    r'@([\p{L}\p{N}_]+)',
    multiLine: true,
    unicode: true
);

the problem is when using these two annotations, multiLine and unicode is not applying, maybe the problem is in this method _mergeRegexPatterns

  RegExp? _mergeRegexPatterns(List<Annotation>? annotations) {
    if (annotations == null || annotations.isEmpty) {
      return null;
    } else if (annotations.length == 1) {
      return annotations[0].regExp;
    }

    // replacing groups '(' => to non capturing groups '(?:'
    return RegExp(
      annotations
          .map(
            (a) =>
                '(${a.regExp.pattern.replaceAll(_nonCapturingGroupPattern, '(?:')})',
          )
          .join('|'),
    );
  }

when merging annotations, it does not apply the other properties of the regex.