Deleting image block doesn't give me the correct deleting node index

1

I have an image block with the following schema:

export const IMAGE_NODE_SPEC: NodeSpec = {
  ...
  atom: true,
  toDOM: () => {
    return ['img'];
  },
  ...
};

When I try to delete the above image block, prosemirror doesn’t seem to give me the correct node index:

    const view = new EditorView(editorRef.current, {
      ...
      dispatchTransaction: (transaction) => {
        const { steps, doc } = transaction;
        if (steps[0] instanceof ReplaceStep) {
          const indexOfDeletingNode = doc.resolve(steps[0].from).index(0);
          // indexOfDeletingNode becomes larger than doc.childCount
          console.log(indexOfDeletingNode, doc.childCount);
        }
        ...
        view.updateState(newState);
      },
      ...
    });

Am I doing something wrong?