doccano/frontend/plugins/filters.js

import Vue from 'vue'

export const truncate = function (text, length, clamp) {
  text = text || ''
  clamp = clamp || '...'
  length = length || 30

  if (text.length <= length) {
    return text
  }

  return text.substring(0, length) + clamp
}

Vue.filter('truncate', truncate)