no-duplicate-attributes.md

Pattern: Duplicate attribute

Issue: -

Description

This rule reports duplicate attributes. When duplicate arguments exist, only the last one is valid.

v-bind:foo directives are handled as the attributes 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>

Further Reading

• eslint-plugin-vue - no-duplicate-attributes