如何在执行梦魇测试期间在多个点评估页面？

Question

我试图编写一个Nightmare.js测试，在测试执行期间在多个点处断言/ evaluate()。

it("should return to home page when quit button is pressed", function (done) {
    var username = 'sinbad';
    new Nightmare({ show: true })
      .goto(url)
      .type('#choosenickname', username)
      .click('#write-btn')
      .wait('div.game')

      .evaluate(function () {
        return document.querySelectorAll('#write-btn').length;
      })
      .then(function (result) {
        // No 'write' buttons found
        result.should.eql(0);
      })
      // Everything after this point doesn't work
      .click('#quit-btn')
      .wait('div.home')
      .evaluate(function () {
        return document.querySelectorAll('#write-btn').length;
      })
      .then(function (result) {
        // After quitting, we should have a write button
        result.should.eql(1);
        done();
      });
  });

当我运行时，我得到了

TypeError: (intermediate value).goto(...).type(...).click(...).wait(...).evaluate(...)
                                 .then(...).click is not a function

Answer 1

根据this sample，答案似乎正在构成then()：

it("should return to home page when quit button is pressed", function (done) {
    var nightmare = loginPlayer('sinbad')
    nightmare
      .evaluate(function () {
        return document.querySelectorAll('#write-btn').length;
      })
      .then(function (result) {
        // No 'write' buttons found
        result.should.eql(0);
      }).then(function () {
        return nightmare
          .click('#quit-btn')
          .wait('div.home')
          .evaluate(function () {
            return document.querySelectorAll('#write-btn').length;
          })
      })
      .then(function (result) {
        // After quitting, we should have a write button
        result.should.eql(1);
        done();
      });
  });