Applying the advice of Vuetify

CtTextField.ts

import mixins from 'vuetify/src/util/mixins';
import VTextField from 'vuetify/lib/components/VTextField';
import VInput from 'vuetify/lib/components/VInput';

export default mixins(VTextField)
  .extend()
  .extend({
    name: 'CtTextField',
    props: {
      dense: {
        type: Boolean,
        default: false
      },
      color: {
        type: String,
        default: 'secondary'
      }
    },
    computed: {
      classes() {
        return {
          ...VInput.options.computed.classes.call(this),
          'v-text-field': true,
          'v-text-field--full-width': this.fullWidth,
          'v-text-field--prefix': this.prefix,
          'v-text-field--single-line': this.isSingle,
          'v-text-field--solo': this.isSolo,
          'v-text-field--solo-inverted': this.soloInverted,
          'v-text-field--solo-flat': this.flat,
          'v-text-field--filled': this.filled,
          'v-text-field--is-booted': this.isBooted,
          'v-text-field--enclosed': this.isEnclosed,
          'v-text-field--reverse': this.reverse,
          'v-text-field--outlined': this.outlined,
          'v-text-field--placeholder': this.placeholder,
          'v-text-field--rounded': this.rounded,
          'v-text-field--shaped': this.shaped,
          'ct-text-field': true,
          'ct-text-field--dense': this.dense
        };
      }
    }
  });