deleteSurroundingPair function

TextCommandResult deleteSurroundingPair(
  1. List<String> graphemes, {
  2. required int cursorOffset,
  3. int? selectionBaseOffset,
  4. int? selectionExtentOffset,
  5. required Map<String, String> surroundPairs,
})

Implementation

TextCommandResult deleteSurroundingPair(
  List<String> graphemes, {
  required int cursorOffset,
  int? selectionBaseOffset,
  int? selectionExtentOffset,
  required Map<String, String> surroundPairs,
}) {
  final selection = normalizedSelectionRange(
    selectionBaseOffset,
    selectionExtentOffset,
  );
  if (selection != null && selection.start != selection.end) {
    return _unchangedResult(
      graphemes,
      cursorOffset: cursorOffset,
      selectionBaseOffset: selectionBaseOffset,
      selectionExtentOffset: selectionExtentOffset,
    );
  }

  if (cursorOffset <= 0 || cursorOffset >= graphemes.length) {
    return _unchangedResult(
      graphemes,
      cursorOffset: cursorOffset,
      selectionBaseOffset: selectionBaseOffset,
      selectionExtentOffset: selectionExtentOffset,
    );
  }

  final opening = graphemes[cursorOffset - 1];
  final closing = graphemes[cursorOffset];
  if (surroundPairs[opening] != closing) {
    return _unchangedResult(
      graphemes,
      cursorOffset: cursorOffset,
      selectionBaseOffset: selectionBaseOffset,
      selectionExtentOffset: selectionExtentOffset,
    );
  }

  final result = edit_ops.removeRange(
    graphemes,
    start: cursorOffset - 1,
    end: cursorOffset + 1,
    cursorOffset: cursorOffset - 1,
  );
  return TextCommandResult(
    graphemes: result.graphemes,
    cursorOffset: result.cursorOffset,
  );
}