期望数组中的项目 [英] Expect item in array

问题描述

我的一个测试期望错误消息文本是多个值之一.由于 getText() 返回一个 promise 我不能使用 toContain() 茉莉花匹配器.以下将不起作用，因为 protractor(jasminewd under-the-hood)不会在匹配器的第二部分 toContain()在这种情况下:

One of my test expects an error message text to be one of multiple values. Since getText() returns a promise I cannot use toContain() jasmine matcher. The following would not work since protractor (jasminewd under-the-hood) would not resolve a promise in the second part of the matcher, toContain() in this case:

expect(["Unknown Error", "Connection Error"]).toContain(page.errorMessage.getText());

问题:有没有办法用 jasmine+protractor 来检查一个元素是否在一个数组中，其中一个元素是一个承诺?

Question: Is there a way to check if an element is in an array with jasmine+protractor where an element is a promise?

换句话说，我正在寻找 toContain() 的逆，以便 expect() 将隐式解析传入的承诺.

In other words, I'm looking for inverse of toContain() so that the expect() would implicitly resolve the promise passed in.

作为一种解决方法，我可以使用 then() 显式解析承诺:

As a workaround, I can explicitly resolve the promise with then():

page.errorMessage.getText().then(function (text) {
    expect(["Unknown Error", "Connection Error"]).toContain(text);
});

我不确定这是否是最佳选择.我也可以接受基于第三方的解决方案，例如 jasmine-matchers.

I'm not sure if this is the best option. I would also be okay with a solution based on third-parties like jasmine-matchers.

举个例子，Python中存在这种断言:

As an example, this kind of assertion exists in Python:

self.assertIn(1, [1, 2, 3, 4]) 

推荐答案

看起来您需要一个自定义匹配器.取决于您使用的 Jasmine 版本:

Looks like you need a custom matcher. Depending on the version of Jasmine you are using:

使用茉莉花 1:

this.addMatchers({
    toBeIn: function(expected) {
        var possibilities = Array.isArray(expected) ? expected : [expected];
        return possibilities.indexOf(this.actual) > -1;
    }
});

使用 Jasmine 2:

this.addMatchers({
    toBeIn: function(util, customEqualityTesters) {
        return {
            compare: function(actual, expected) {
                var possibilities = Array.isArray(expected) ? expected : [expected];
                var passed = possibilities.indexOf(actual) > -1;

                return {
                    pass: passed,
                    message: 'Expected [' + possibilities.join(', ') + ']' + (passed ? ' not' : '') + ' to contain ' + actual
                };
            }
        };
    }
});

您必须在将要在其中使用的每个 describe 块的 beforeEach 部分中执行此操作.

You'll have to execute this in the beforeEach section on each of your describe blocks it's going to be used in.

您的期望如下:

expect(page.errorMessage.getText()).toBeIn(["Unknown Error", "Connection Error"]);

这篇关于期望数组中的项目的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！