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/* eslint-env jest */

const chai = require('chai')
const chaiAsPromised = require('chai-as-promised')
const expect = chai.expect

// use chai-as-promised
chai.use(chaiAsPromised)

// a simple async function which throws an error
async function exampleAsyncFunction () {
  throw Error('Message with some message fragment inside')
}

describe('exampleAsyncFunction', () => {

  // this case will result as OK
  it('check for value which is exact match to the error message', () => {
    return expect(exampleAsyncFunction())
      .to.be.rejectedWith(Error, 'Message with some message fragment inside')
  })

  // this case will result as OK, partial error message is checked
  it('check for value which is contained by the error message', () => {
    return expect(exampleAsyncFunction())
      .to.be.rejectedWith(Error, /message fragment/)
  })

  // this case will result with AssertionError: expected promise
  // to be rejected with an error matching /message missing fragment/ but
  // got 'Message with some message fragment inside'
  it('check for value which is NOT contained by the error message', () => {
    return expect(exampleAsyncFunction())
      .to.be.rejectedWith(Error, /message missing fragment/)
  })
})