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Tag: jestjs

In Jest, how do I cause a function called within the function to return a specific value

This is the function I am testing (stripped down for simplicity’s sake): populate.js-> The function this function calls: populate-template-utilities -> And my unit test (again stripped down): I want createSessionID to return ‘PAX123456’ and think mockID should do it, but it’s erroring with: Answer The spyOn method needs at least two parameters: object and methodName. Try sth like this: It

How to store response body in supertest?

I am testing very basic REST api with supertest. I want to save the item id received in response body and assign it to a variable. Using this id i want to make further tests like get-item-by-id or update-item-by-id. No official documentation has covered this so a beginner friendly answer would be very helpful. test i have written Answer Use

Mock an axios 404 with Jest?

When mocking a 404 error the result is Uncaught UnhandledPromiseRejection: This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). The promise rejected with the reason “Error: error”. Setup a basic Mock Create a test case How to mock the 404 request? Answer Using

Jest redux saga API call with response image

I’m trying to test a fetch that responds with a readable stream for an image, but I’m stuck and not sure how to approach this specific case. Is there a simple, easy way to mock the call’s response? Any help would be appreciated 😀 The generator function looks like the following: Answer You can use testing the saga generator function