I am learning React, and got stuck in testing one of my components. I use react-use-cart to manage the cart, this is how code looks The test breaks at “productInCart = getItem(product.id)” saying ” TypeError: getItem is not a function”. I’ve been stuck at this for several days, and would really appreciate some help, it’s my first time asking a
Tag: jestjs
Why jest is not working with imported test data?
Here a test data defined in sum-test-cases.js with the following Here is the jest test file sum.test.js with the following The test failed with the following error: However, instead of importing the data from another file, if I define the data within the test file like the following, the test works as expected. The test data is exactly the same,
Jest skipping S3 Get Object call in function
Im testing a standard S3 Get Object Call, but when Jest tests my function, it skips the Get Object call and jumps to end of function, ending the execution and returning nothing. When I checked code coverage, all lines are covered expect the getObject call. This is my s3 file being tested. I have checkpoints there to show that the
Check if type of emitted variable matches custom type
I am testing some Vue 3 components with jest and expect to get an emit when a button is clicked. Now I want to check if the object emitted matches a custom type I created in a different file. e.g.: My test case looks something like this: But here I get the error Element is not accessible at customType even
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
How to call multi variable array in JS function?
I’m using this function to select one item in drop down menu: Now I want to select multi item before “await this.select();” this step. I tried to edit function like this: but when I call this function to select multi item it has error Expected 0-1 arguments, but got 3 How do I fix this? Answer You can make a
How to mock instance methods of a class mocked with jest.mock?
How can the instance methods be mocked for a class that is being mocked with jest.mock? For example, a class Logger is mocked: Answer Automatic Mocking Calling jest.mock automatically mocks all the exports from the module being mocked unless a manual mock is specified using the __mocks__ directory. So, this line jest.mock(“./Logger”) has automatically replaced the Logger constructor and all
How to mock a constructor instantiated class instance using jest?
Given a class Person that instantiates & uses another class Logger, how can the Logger’s method be verified to be called when Person is instantiated in the example below? One option is to pass Logger as a constructor argument like below: However, is there any other way without changing the constructor to complete the test? Answer You can use jest.mock(moduleName,
how to spy on window.location functions?
i need to cover my code with some unit tests and in one of then i have the following situation. app.tsx and in my test file i’m getting the followein error : Cannot assign to read only property ‘replace’ of object ‘[object Location]’ i’ve tried other aproachs like }); but i get different erros for each one of them, is
Debugging jest mocks
I’ve got a library that’s giving me some trouble in my jest tests. This library is included throughout my project, and it has an annoyingFunction that has a console.error in it. So, whenever I run a test, I naturally get unwanted console.error messages all over the place. I don’t want to mock out the whole library, just the annoyingFunction, so