Jest.js错误:“收到:序列化为相同的字符串" [英] Jest.js error: "Received: serializes to the same string"
问题描述
此测试存在一个奇怪的问题:
I've having a strange problem with this test:
import Deal from "../src/models/Deal";
import apiProducts from "../__mocks__/api/products";
describe("Deal", () => {
describe("Deal.fromApi", () => {
it("takes an api product and returns a Deal", () => {
const apiDeal = apiProducts[0];
const newDeal = Deal.fromApi(apiDeal);
const expected = expectedDeal();
expect(newDeal).toEqual(expected);
});
});
});
Deal.js
export default class Deal {
// no constructor since we only ever create a deal from Deal.fromApi
static fromApi(obj: Object): Deal {
const deal = new Deal();
deal.id = obj.id;
deal.name = obj.name;
deal.slug = obj.slug;
deal.permalink = obj.permalink;
deal.dateCreated = obj.date_created;
deal.dateModified = obj.date_modified;
deal.status = obj.status;
deal.featured = obj.featured;
deal.catalogVisibility = obj.catalog_visibility;
deal.descriptionHTML = obj.description;
deal.shortDescriptionHTML = obj.short_description;
deal.price = Number(obj.price);
deal.regularPrice = Number(obj.regular_price);
deal.salePrice = Number(obj.sale_price);
deal.dateOnSaleFrom = obj.date_on_sale_from;
deal.dateOnSaleTo = obj.date_on_sale_to;
deal.onSale = obj.on_sale;
deal.purchasable = obj.purchasable;
deal.relatedIds = obj.related_ids;
deal.upsellIds = obj.upsell_ids;
deal.crossSellIds = obj.cross_sell_ids;
deal.categories = obj.categories;
deal.tags = obj.tags;
deal.images = obj.images;
return deal;
}
descriptionWithTextSize(size: number): string {
return this.descriptionWithStyle(`font-size:${size}`);
}
descriptionWithStyle(style: string): string {
return `<div style="${style}">${this.description}</div>`;
}
distanceFromLocation = (
location: Location,
unit: unitOfDistance = "mi"
): number => {
return distanceBetween(this.location, location);
};
distanceFrom = (otherDeal: Deal, unit: unitOfDistance = "mi"): number => {
return distanceBetween(this.location, otherDeal.location);
};
static toApi(deal: Deal): Object {
return { ...deal };
}
}
测试失败，并显示以下错误:
The test fails with this error:
● Deal › Deal.fromApi › takes an api product and returns a Deal
expect(received).toEqual(expected) // deep equality
Expected: {"catalogVisibility": "visible", "categories": [{"id": 15, "name": "New York", "slug": "new-york"}], "crossSellIds": [34, 31], "dateCreated": "2019-05-18T17:36:14", "dateModified": "2019-05-18T17:39:02", "dateOnSaleFrom": null, "dateOnSaleTo": null, "descriptionHTML": "<p>Pete's Tavern<br />
129 E 18th St<br />
New York, NY 10003</p>
<p>Weekdays from 4 p.m. to 7 p.m.<br />
$5 wines and beers</p>
", "distanceFromLocation": [Function anonymous], "featured": false, "id": 566, "images": [{"alt": "", "date_created": "2019-05-18T17:38:52", "date_created_gmt": "2019-05-18T17:38:52", "date_modified": "2019-05-18T17:38:52", "date_modified_gmt": "2019-05-18T17:38:52", "id": 567, "name": "wine and beers2", "src": "https://tragodeals.com/wp-content/uploads/2019/05/wine-and-beers2.jpg"}], "name": "Wines and beers", "onSale": true, "permalink": "https://tragodeals.com/product/wines-and-beers/", "price": 5, "purchasable": true, "regularPrice": 11, "relatedIds": [552, 564, 390, 37, 543], "salePrice": 5, "shortDescriptionHTML": "<p>$5 wines and beers</p>
", "slug": "wines-and-beers", "status": "publish", "tags": [{"id": 58, "name": "beers", "slug": "beers"}, {"id": 54, "name": "Cocktails", "slug": "cocktails"}, {"id": 45, "name": "drink", "slug": "drink"}, {"id": 57, "name": "wine", "slug": "wine"}], "upsellIds": [53]}
Received: serializes to the same string
> 15 | expect(newDeal).toEqual(expected);
| ^
16 | });
17 | });
18 | });
at Object.toEqual (__tests__/deal.test.js:15:23)
我插入了此循环以进行调查:
I inserted this loop to investigate:
for (let key in expected) {
expect(expected[key]).toEqual(newDeal[key]);
}
我看到问题出在函数上.因此，我将整个测试更改为:
And I see that the problem is with functions. So I changed the whole test to this:
for (let key in expected) {
if (typeof expected[key] === "function") continue;
expect(expected[key]).toEqual(newDeal[key]);
}
// expect(newDeal).toEqual(expected);
它通过了，并且在应有的情况下也失败了. (如果您阅读了这个问题的旧版本，而我却通过了我不理解的测试，那是因为当我应该continue ing时，我正在循环中return).
And it passes, and also fails when it should. (if you read the old version of this question where I was getting passing tests that I didn't understand, it was because I was returning from the loop when I should have been continueing).
但是我希望能够使用标准断言expect(newDeal).toEqual(expected)来做到这一点.在检查类对象(Deal)与函数的相等性方面，我似乎不太了解.
But I'd like to be able to do it with the standard assertion expect(newDeal).toEqual(expected). It looks like there's something I'm not understanding about checking for class object (Deal) equality with functions.
PS.您可能建议使用toMatchObject.但是，可悲的是:
PS. You might suggest using toMatchObject. But, sadly:
● Deal › Deal.fromApi › takes an api product and returns a Deal
expect(received).toMatchObject(expected)
- Expected
+ Received
@@ -1,6 +1,6 @@
- Deal {
+ Object {
"address": "129 E 18th St New York, NY 10003",
"catalogVisibility": "visible",
"categories": Array [
Object {
"id": 15,
13 | expect(expected[key]).toEqual(newDeal[key]);
14 | }
> 15 | expect(newDeal).toMatchObject(expected);
| ^
16 | });
17 | });
18 | });
推荐答案
当尝试比较数组时，在一个数组中有一个元素设置为-1索引的元素时遇到了这个问题(想象除了从0至N). 因此，在以下情况下您可能会遇到此错误:
Just had this problem when tried to compare arrays where in one array there was an element with -1 index set (imagine any other key to be set except numbers from 0 to N). So you may have this error in the following scenario:
const arr = [1, 2]
arr[-1] = 'foo'
expect(arr).toEqual([1, 2])
它们都序列化为相同的字符串，但是不相等.
They both serialized to the same string, but they are not equal.
这篇关于Jest.js错误:“收到:序列化为相同的字符串"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！
