javascript - mailListner-无法读取未定义的属性“on”

我正在使用以下mailListner库进行E2E量角器测试，并且还基于该posting中的信息，看起来不错。

我面临的问题与功能getLastEmail()有关：

import { mailListener } from 'mail-listener2';

function getLastEmail() {
    const deferred = protractor.promise.defer();
    console.log("Waiting for an email...");

    mailListener.on("mail", function(mail){
        deferred.fulfill(mail);
    });
    return deferred.promise;
}

运行测试时，我不断收到错误消息：
- Failed: Cannot read property 'on' of undefined

看来mailListner是未定义的。

这是调用函数的部分：

describe('sales App', () => {
   it('Should send confirmation email', () => {

      browser.controlFlow().wait(getLastEmail())
            .then((email) => {
                expect(email['subject']).toEqual("Confirm Registration");
                expect(email['headers'].to).toEqual("[email protected]");
                const pattern = /Registration code is: (\w+)/g;
                const regCode = pattern.exec(email['text'])[1];
                console.log(regCode);

            });
   });
});

protractor.confi.js：

onPrepare() {
    require('ts-node').register({
        project: 'e2e/tsconfig.e2e.json'
    });
    jasmine.getEnv().addReporter(new SpecReporter({ spec: { displayStacktrace: true } }));

    var MailListener = require("mail-listener2");
    // here goes your email connection configuration
    var mailListener = new MailListener({
        username: "[email protected]",
        password: "MyPassword",
        host: "imap.gmail.com",
        port: 993, // imap port
        tls: true,
        tlsOptions: { rejectUnauthorized: false },
        mailbox: "INBOX", // mailbox to monitor
        searchFilter: ["UNSEEN", "FLAGGED"], // the search filter being used after an IDLE notification has been retrieved
        markSeen: true, // all fetched email willbe marked as seen and not fetched next time
        fetchUnreadOnStart: true, // use it only if you want to get all unread email on lib start. Default is `false`,
        mailParserOptions: { streamAttachments: true }, // options to be passed to mailParser lib.
        attachments: true, // download attachments as they are encountered to the project directory
        attachmentOptions: { directory: "attachments/" } // specify a download directory for attachments
    });

    mailListener.start()

    mailListener.on("server:connected", function() {
        console.log("Mail listener initialized")
    })

    mailListener.on("error", function(err) {
        console.log(err)
    })

    mailListener.on("server:disconnected", function() {
        console.log("imapDisconnected")
    })

    global.mailListener = mailListener


},
onCleanUp: function() {
    mailListener.stop()
}

任何想法如何解决和修复它？

最佳答案

我猜它是在引用mailListener.on("mail"...这行，所以您的mailListener是不确定的。

如果您最初遵循this answer并在配置中实例化mailListener，您会注意到它们为mailListener创建了一个全局变量，该全局变量在调用getLastEmail时可用。

或者，如果您在规范中（例如，在beforeAll块中）执行此操作，则在实例化它时仍会创建一个引用mailListener的变量，然后将其传递给函数。

// page objects
getLastEmail = function (serv) {
    var deferred = protractor.promise.defer();
    console.log("Waiting for an email...");

    serv.on("mail", function(mail){
        console.log('Email received, parsing...');
        deferred.fulfill(mail);
    });
    return deferred.promise;
};

// specs
const MailListener = require("mail-listener2");
mailListener = new MailListener({...
browser.wait(Util.getLastEmail(mailListener), 30000).then(function (mail) {...