vue/test/unit/modules/util/error.spec.ts

import Vue from 'vue'
import { invokeWithErrorHandling } from 'core/util/error'

describe('invokeWithErrorHandling', () => {
  if (typeof Promise !== 'undefined') {
    it('should errorHandler call once when nested calls return rejected promise', done => {
      const originalHandler = Vue.config.errorHandler
      const handler = (Vue.config.errorHandler = vi.fn())
      const userCatch = vi.fn()
      const err = new Error('fake error')

      invokeWithErrorHandling(() => {
        return invokeWithErrorHandling(() => {
          return Promise.reject(err)
        })
      })
        .catch(userCatch)
        .then(() => {
          Vue.config.errorHandler = originalHandler
          expect(handler.mock.calls.length).toBe(1)
          expect(userCatch).toHaveBeenCalledWith(err)
          done()
        })
    })
  }
})