Protractor - 当 DOM 元素更改时，页面对象不会更新

我正在测试使用 angular.js 构建的 SPA，并使用页面对象模式来编写我的测试。在应用程序中，我们有许多将要更新的列表。例如，有一个附件列表，当添加/删除附件时，该列表将会更新。要添加附件，我们有一个模式窗口，当我们上传文件并单击“确定”时。文件上传并更新列表。

我编写了 2 个页面对象，一个用于上传模式窗口，另一个用于附件列表的预览。在我的测试中，我首先获取附件的当前数量，然后单击按钮激活模式窗口并附加文件。然后我再次对预览页面中的附件进行计数，并进行比较，使其增加 1。但测试失败。页面对象未更新，并且附件计数仍显示为 2。

Test

it('Should attach a file when a file is selected and OK button is pressed.', function () {
            var currentFileCount = viewMeetingTabPage.getMeetingAttachmentCount();

            viewMeetingPage.clickAddAttachmentButton();
            addAttchmentPage.attachFile();
            addAttchmentPage.clickConfimAttachFileButton();

            currentFileCount.then(function (curCount) {
                viewMeetingTabPage.getMeetingAttachmentCount().then(function (newCount) {
                    expect(newCount).toBe(curCount + 1);
                    //expect(viewMeetingTabPage.getMeetingAttachmentName()).toBe('test-file.pdf');
                });
            });
        });

查看会议选项卡页面

this.getMeetingAttchments = function () {
        return element.all(by.repeater('attachment in meeting.AttachmentViewModelList track by $index'));
    };

this.getMeetingAttachmentCount = function () {
        return this.getMeetingAttchments().count();
    };

我需要的是在上传文件后以某种方式更新页面对象。我怎样才能做到这一点。

这就是如何控制流 https://github.com/angular/protractor/blob/master/docs/control-flow.md作品。执行测试代码会排队一堆承诺。它们按照添加到流程中的顺序得到解决，同时每个都等待前一个完成。

it('Should attach a file when a file is selected and OK button is pressed.', function () {
        # Queues the count promise
        var currentFileCount = viewMeetingTabPage.getMeetingAttachmentCount();

        # Queues some other promises that would start
        # to get executed once the one above finishes
        viewMeetingPage.clickAddAttachmentButton();
        addAttchmentPage.attachFile();
        addAttchmentPage.clickConfimAttachFileButton();

        # This piece of code branches-off the control-flow
        # and gets executed immediately after currentFileCount is resolved
        # i.e. before the clickAddAttachmentButton
        currentFileCount.then(function (curCount) {
            # That's why newCount equals curCount,
            # they are counting the same number of elements
            # since nothing changed in the meantime
            viewMeetingTabPage.getMeetingAttachmentCount().then(function (newCount) {
                expect(newCount).toBe(curCount + 1);
                //expect(viewMeetingTabPage.getMeetingAttachmentName()).toBe('test-file.pdf');
            });
        });
    });

currentFileCount可以被视为测试的设置阶段，因此您可以将其提取到beforeEach block:

var initialFileCount;
beforeEach(function() {
    viewMeetingTabPage.getMeetingAttachmentCount().then(function(count) {
        initialFileCount = count;
    });
});

it('Should attach a file when a file is selected and OK button is pressed.', function () {
    viewMeetingPage.clickAddAttachmentButton();
    addAttchmentPage.attachFile();
    addAttchmentPage.clickConfimAttachFileButton();
    expect(viewMeetingTabPage.getMeetingAttachmentCount()).toBe(initialFileCount + 1);
});

由于 Protractor 修补 jasmine 以便在测试块之间等待控制流清空，因此这可能会起作用。

记住expect还进行了修补以处理承诺，因此您无需将其放在then.

UPDATE:

事实上，你不应该需要beforeEach上面，它也应该像这样工作：

var initialFileCount;

it('Should attach a file when a file is selected and OK button is pressed.', function () {
    viewMeetingTabPage.getMeetingAttachmentCount().then(function(count) {
        initialFileCount = count;
    });
    viewMeetingPage.clickAddAttachmentButton();
    addAttchmentPage.attachFile();
    addAttchmentPage.clickConfimAttachFileButton();
    expect(viewMeetingTabPage.getMeetingAttachmentCount()).toBe(initialFileCount + 1);
});

这就是所谓的框架WebDriverJS 用户指南 https://github.com/SeleniumHQ/selenium/wiki/WebDriverJs#framing.