Proper way of returning errors on responseFromOperation hook?

Hi! I was hoping on using a plugin to capture a query and return something else in its stead, in this case, an error, while receiving that at the other end of the plugin with willSendResponse, example:

      {
        async requestDidStart() {
          return {
            async responseForOperation({ context }) {
              return {
                errors: [new GraphQLError('Everything exploded')],
                data: null,
              };
            },

            async willSendResponse({ context, errors }) {
              console.log(errors, '<------ errors should be here?');
            },
          };
        },
      },

In this example, while the graphql server result is as expected, errors in willSendResponse is always undefined. Throwing the error also produces the expected result but willSendResponse does not trigger at all.

I have a testing environment here: Graphql (forked) - StackBlitz
use the following query:

query {
  hello { message }
}