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jestjs, Programming

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Console.log statements output nothing at all in Jest

console.log statements output nothing at all in Jest. This was working for me yesterday, and all of sudden, it’s not working today. I ...

June 2, 2022
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javascript, Programming

IT Nursery

Jest: how to test for object keys and values?

I have a mapModule where I import components and export them: import ComponentName from '../components/ComponentName'; export default { name: ComponentName, }; How can ...

May 31, 2022
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jestjs, Programming

IT Nursery

How do I deal with localStorage in jest tests?

I keep getting “localStorage is not defined” in Jest tests which makes sense but what are my options? Hitting brick walls. 25 Answers ...

May 31, 2022
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jestjs, Programming

IT Nursery

How can I clear the Jest cache?

Jest is picking up an old version of a package and thus my tests fail unless I use --no-cache. I can even delete ...

May 27, 2022
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javascript, Programming

IT Nursery

How to get the code coverage report using Jest?

Is there a way to have code coverage in the JavaScript Jest testing framework, which is built on top of Jasmine? The internal ...

May 27, 2022
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How do I set a mock date in Jest?

I’m using moment.js to do most of my date logic in a helper file for my React components but I haven’t been able ...

May 25, 2022
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Test process.env with Jest

I have an application that depends on environmental variables like: const APP_PORT = process.env.APP_PORT || 8080; And I would like to test that ...

May 25, 2022
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How to run Jest tests sequentially?

I’m running Jest tests via npm test. Jest runs tests in parallel by default. Is there any way to make the tests run ...

May 24, 2022
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How do you test for the non-existence of an element using jest and react-testing-library?

I have a component library that I’m writing unit tests for using Jest and react-testing-library. Based on certain props or events I want ...

May 24, 2022
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Can you write async tests that expect toThrow?

I’m writing an async test that expects the async function to throw like this: it("expects to have failed", async () => { let ...

May 19, 2022
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