Vue template or render function not defined yet I am using neither?

This is my main javascript file:

import Vue from 'vue'

new Vue({
  el: '#app'
});

My HTML file:

<body>
    <div id="app"></div>

    <script src="{{ mix('/js/app.js') }}"></script>
</body>

Webpack configuration of Vue.js with the runtime build:

alias: {
    'vue$': 'vue/dist/vue.runtime.common.js'
}

I am still getting this well known error:

[Vue warn]: Failed to mount component: template or render function not defined. (found in root instance)

How come when I don't even have a single thing inside my #app div where I mount Vue, I am still getting a render/template error? It says found in root but there is nothing to be found because it does not even have any content?

How am I suppose to mount if this does not work?

Edit:

I have tried it like this which seems to work:

new Vue(App).$mount('#app');

It make sense because using the el property implies you are 'scanning' that dom element for any components and it's useless because the runtime build does not have a compiler.

Still it is an extremely strange error message to throw, especially when I have my entire #app div emptied out.

Hopefully somebody could confirm my thoughts.

Solution

The reason you're receiving that error is that you're using the runtime build which doesn't support templates in HTML files as seen here vuejs.org

In essence what happens with vue loaded files is that their templates are compile time converted into render functions where as your base function was trying to compile from your html element.