Extend VTextField from vuetify that toggles password field visibility

PasswordToggle.vue

<script>
import VTextField from 'vuetify/es5/components/VTextField'
import VInput from 'vuetify/es5/mixins/input.js'
export default {
  extends: VTextField,
  data: () => {
    return {
      customAppendIcon: 'visibility_off',
      customType: 'password'
    }
  },
  methods: {
    genInput () {
      let genInput = VTextField.methods.genInput.call(this)
      genInput[0].data.attrs.type = this.customAppendIcon.includes('_off') ? 'password' : 'text'
      return genInput
    },
    genIcon (type, defaultCallback = null) {
      let resultIcon = VInput.methods.genIcon.call(this, type, defaultCallback)
      if (type === 'append')resultIcon.children[0].text = this.customAppendIcon
      return resultIcon
    }
  },
  render () {
    let that = this
    return this.genInputGroup(this.genInput(), { attrs: { tabindex: false } }, () => {
      if (that.customAppendIcon.includes('_off')) { that.customAppendIcon = 'visibility' } else { that.customAppendIcon = 'visibility_off' }
    })
  }
}
</script>