int previousBreak()

in lib/src/grapheme_clusters/breaks.dart [300:329]

• 30 lines of code
• 8 McCabe index (conditional complexity)

int previousBreak(String text, int start, int end, int index) {
  assert(0 <= start);
  assert(start <= index);
  assert(index <= end);
  assert(end <= text.length);
  if (index == start || index == end) return index;
  var indexBefore = index;
  var nextChar = text.codeUnitAt(index);
  var category = categoryControl;
  if (nextChar & 0xF800 != 0xD800) {
    category = low(nextChar);
  } else if (nextChar & 0xFC00 == 0xD800) {
    var indexAfter = index + 1;
    if (indexAfter < end) {
      var secondChar = text.codeUnitAt(indexAfter);
      if (secondChar & 0xFC00 == 0xDC00) {
        category = high(nextChar, secondChar);
      }
    }
  } else {
    var prevChar = text.codeUnitAt(index - 1);
    if (prevChar & 0xFC00 == 0xD800) {
      category = high(prevChar, nextChar);
      indexBefore -= 1;
    }
  }
  return BackBreaks(
          text, indexBefore, start, moveBack(stateEoTNoBreak, category))
      .nextBreak();
}