int? findLineStart()

in lib/src/utils.dart [63:91]

• 23 lines of code
• 9 McCabe index (conditional complexity)

int? findLineStart(String context, String text, int column) {
  // If the text is empty, we just want to find the first line that has at least
  // [column] characters.
  if (text.isEmpty) {
    var beginningOfLine = 0;
    while (true) {
      final index = context.indexOf('\n', beginningOfLine);
      if (index == -1) {
        return context.length - beginningOfLine >= column
            ? beginningOfLine
            : null;
      }

      if (index - beginningOfLine >= column) return beginningOfLine;
      beginningOfLine = index + 1;
    }
  }

  var index = context.indexOf(text);
  while (index != -1) {
    // Start looking before [index] in case [text] starts with a newline.
    final lineStart = index == 0 ? 0 : context.lastIndexOf('\n', index - 1) + 1;
    final textColumn = index - lineStart;
    if (column == textColumn) return lineStart;
    index = context.indexOf(text, index + 1);
  }
  // ignore: avoid_returning_null
  return null;
}