function getEntityRemovalRange()

in src/model/modifier/getCharacterRemovalRange.js [114:179]
52 lines of code
6 McCabe index (conditional complexity)

function getEntityRemovalRange(
  entityMap: EntityMap,
  block: BlockNodeRecord,
  selectionState: SelectionState,
  direction: DraftRemovalDirection,
  entityKey: string,
  isEntireSelectionWithinEntity: boolean,
  isEntityAtStart: boolean,
): SelectionState {
  let start = selectionState.getStartOffset();
  let end = selectionState.getEndOffset();
  const entity = entityMap.get(entityKey);
  const mutability = entity.getMutability();
  const sideToConsider = isEntityAtStart ? start : end;

  // `MUTABLE` entities can just have the specified range of text removed
  // directly. No adjustments are needed.
  if (mutability === 'MUTABLE') {
    return selectionState;
  }

  // Find the entity range that overlaps with our removal range.
  const entityRanges = getRangesForDraftEntity(block, entityKey).filter(
    range => sideToConsider <= range.end && sideToConsider >= range.start,
  );

  invariant(
    entityRanges.length == 1,
    'There should only be one entity range within this removal range.',
  );

  const entityRange = entityRanges[0];

  // For `IMMUTABLE` entity types, we will remove the entire entity range.
  if (mutability === 'IMMUTABLE') {
    return selectionState.merge({
      anchorOffset: entityRange.start,
      focusOffset: entityRange.end,
      isBackward: false,
    });
  }

  // For `SEGMENTED` entity types, determine the appropriate segment to
  // remove.
  if (!isEntireSelectionWithinEntity) {
    if (isEntityAtStart) {
      end = entityRange.end;
    } else {
      start = entityRange.start;
    }
  }

  const removalRange = DraftEntitySegments.getRemovalRange(
    start,
    end,
    block.getText().slice(entityRange.start, entityRange.end),
    entityRange.start,
    direction,
  );

  return selectionState.merge({
    anchorOffset: removalRange.start,
    focusOffset: removalRange.end,
    isBackward: false,
  });
}