require-explicit-emits.md

pageClass	sidebarDepth	title	description	since
rule-details	0	vue/require-explicit-emits	require `emits` option with name triggered by `$emit()`	v7.0.0

vue/require-explicit-emits

require emits option with name triggered by $emit()

• ⚙️ This rule is included in "plugin:vue/vue3-strongly-recommended" and "plugin:vue/vue3-recommended".
• 💡 Some problems reported by this rule are manually fixable by editor suggestions.

📖 Rule Details

This rule reports event triggers not declared with the emits option. (The emits option is a new in Vue.js 3.0.0+)

Explicit emits declaration serves as self-documenting code. This can be useful for other developers to instantly understand what events the component is supposed to emit. Also, with attribute fallthrough changes in Vue.js 3.0.0+, v-on listeners on components will fallthrough as native listeners by default. Declare it as a component-only event in emits to avoid unnecessary registration of native listeners.

<template>
  <!-- ✓ GOOD -->
  <div @click="$emit('good')"/>
  <!-- ✗ BAD -->
  <div @click="$emit('bad')"/>
</template>
<script>
export default {
  emits: ['good']
}
</script>

<script>
export default {
  emits: ['good'],
  methods: {
    foo () {
      // ✓ GOOD
      this.$emit('good')
      // ✗ BAD
      this.$emit('bad')
    }
  }
}
</script>

<script>
export default {
  emits: ['good'],
  setup (props, context) {
    // ✓ GOOD
    context.emit('good')
    // ✗ BAD
    context.emit('bad')
  }
}
</script>

🔧 Options

{
  "vue/require-explicit-emits": ["error", {
    "allowProps": false
  }]
}

• "allowProps" ... If true, allow event names defined in props. default false

"allowProps": true

<script>
export default {
  props: ['onGood', 'bad'],
  methods: {
    foo () {
      // ✓ GOOD
      this.$emit('good')
      // ✗ BAD
      this.$emit('bad')
    }
  }
}
</script>

📚 Further Reading

• Guide - Custom Events / Defining Custom Events
• Vue RFCs - 0030-emits-option

🚀 Version

This rule was introduced in eslint-plugin-vue v7.0.0

🔍 Implementation

• Rule source
• Test source