writefreely/prose/menu.js

import { MenuItem } from "prosemirror-menu";
import { buildMenuItems } from "prosemirror-example-setup";

import { writeFreelySchema } from "./schema";

function canInsert(state, nodeType, attrs) {
    let $from = state.selection.$from
    for (let d = $from.depth; d >= 0; d--) {
      let index = $from.index(d)
      if ($from.node(d).canReplaceWith(index, index, nodeType, attrs)) return true
    }
    return false
  }

const ReadMoreItem = new MenuItem({
    label: "Read more",
    select: (state) => canInsert(state, writeFreelySchema.nodes.readmore),
    run(state, dispatch) {
        dispatch(state.tr.replaceSelectionWith(writeFreelySchema.nodes.readmore.create()))
    },
});

export const getMenu = ()=> {
    const menuContent = [...buildMenuItems(writeFreelySchema).fullMenu, [ReadMoreItem]];
    return menuContent
}