Provide the function to check slot like checking props

<template>
  <div>
    <header><slot name="header" /></header>
    <div><slot /></div>
  </div>
</template>

<script>
export default {
  slots: ['default', 'header'], // require default slot and header slot
};
</script>

<template>
  <div>
    <SampleComponent />
  </div>
</template>

$ yarn add vue-slot-checker

import Vue from 'vue';
import VueSlotChecker from 'vue-slot-checker';
 
Vue.use(VueSlotChecker);

<script>
import { vueSlotCheckerMixin } from 'vue-slot-checker';

export default {
  mixins: [vueSlotCheckerMixin],
};
</script>

export default {
  slots: true,
};

export default {
  slots: ['default', 'header'],
};

export default {
  slots: {
    default: {
      required: true,
    },
    header: {
      validator(slot) {
        if (typeof slot === 'undefined') {
          return false;
        }
        return typeof slot[0].tag === 'undefined' && typeof slot[0].text === 'string';
      },
    },
  },
};

import Vue from 'vue';
import VueSlotChecker from 'vue-slot-checker';
 
Vue.use(VueSlotChecker, {
  silent: true,
});

import Vue from 'vue';
import VueSlotChecker from 'vue-slot-checker';

// When not used as a plugin
if (process.env.NODE_ENV === 'development') {
  Vue.use(VueSlotChecker);
}

// When using the silent option
Vue.use(VueSlotChecker, {
  silent: process.env.NODE_ENV !== 'development'
});

// When using the Vue.config.silent
Vue.config.silent = process.env.NODE_ENV !== 'development';
Vue.use(VueSlotChecker);