no-duplicate-attributes.md

pageClass	sidebarDepth	title	description	since
rule-details	0	vue/no-duplicate-attributes	disallow duplication of attributes	v3.0.0

vue/no-duplicate-attributes

disallow duplication of attributes

• ⚙️ This rule is included in all of "plugin:vue/vue3-essential", *.configs["flat/essential"], "plugin:vue/essential", *.configs["flat/vue2-essential"], "plugin:vue/vue3-strongly-recommended", *.configs["flat/strongly-recommended"], "plugin:vue/strongly-recommended", *.configs["flat/vue2-strongly-recommended"], "plugin:vue/vue3-recommended", *.configs["flat/recommended"], "plugin:vue/recommended" and *.configs["flat/vue2-recommended"].

When there are multiple attributes with the same name on a component, only the last one is used and the rest are ignored, so this is usually a mistake.

📖 Rule Details

This rule reports duplicate attributes. v-bind:foo directives are handled as the attribute foo.

<template>
  <!-- ✓ GOOD -->
  <MyComponent :foo="abc" />
  <MyComponent foo="abc" />
  <MyComponent class="abc" :class="def" />

  <!-- ✗ BAD -->
  <MyComponent :foo="abc" foo="def" />
  <MyComponent foo="abc" :foo="def" />
  <MyComponent foo="abc" foo="def" />
  <MyComponent :foo.a="abc" :foo.b="def" />
  <MyComponent class="abc" class="def" />
</template>

🔧 Options

{
  "vue/no-duplicate-attributes": ["error", {
    "allowCoexistClass": true,
    "allowCoexistStyle": true
  }]
}

• allowCoexistClass (boolean) ... Enables v-bind:class directive can coexist with the plain class attribute. Default is true.
• allowCoexistStyle (boolean) ... Enables v-bind:style directive can coexist with the plain style attribute. Default is true.

"allowCoexistClass": false, "allowCoexistStyle": false

<template>
  <!-- ✗ BAD -->
  <MyComponent class="abc" :class="def" />
  <MyComponent style="abc" :style="def" />
</template>

🚀 Version

This rule was introduced in eslint-plugin-vue v3.0.0

🔍 Implementation

• Rule source
• Test source