function moveSelectionBackward()

in src/component/handlers/edit/commands/moveSelectionBackward.js [27:62]

• 32 lines of code
• 3 McCabe index (conditional complexity)

function moveSelectionBackward(
  editorState: EditorState,
  maxDistance: number,
): SelectionState {
  const selection = editorState.getSelection();
  // Should eventually make this an invariant
  warning(
    selection.isCollapsed(),
    'moveSelectionBackward should only be called with a collapsed SelectionState',
  );
  const content = editorState.getCurrentContent();
  const key = selection.getStartKey();
  const offset = selection.getStartOffset();

  let focusKey = key;
  let focusOffset = 0;

  if (maxDistance > offset) {
    const keyBefore = content.getKeyBefore(key);
    if (keyBefore == null) {
      focusKey = key;
    } else {
      focusKey = keyBefore;
      const blockBefore = content.getBlockForKey(keyBefore);
      focusOffset = blockBefore.getText().length;
    }
  } else {
    focusOffset = offset - maxDistance;
  }

  return selection.merge({
    focusKey,
    focusOffset,
    isBackward: true,
  });
}