jest-env.js

const Environment = require('jest-environment-jsdom-global')
/**
 * A custom environment to set the TextEncoder
 */
module.exports = class CustomTestEnvironment extends Environment {
  constructor ({ globalConfig, projectConfig }, context) {
    super({ globalConfig, projectConfig }, context)
    if (typeof this.global.TextEncoder === 'undefined') {
      const { TextEncoder } = require('util')
      this.global.TextEncoder = TextEncoder
    }
  }
}