Jest Referenceerror Function Is Not Defined, test (in package. If I comment out mocking my function, I then get a ReferenceError about fetch The ReferenceError: jest is not defined in ESM projects is almost always due to misconfiguration between Jest, Node. If you'd like to use jest, you'd need to . When MyComponent is transpiled with babel and run in the browser, the dependency operates correctly. To access it you must run your tests in How can I solve "ReferenceError: expect is not defined" error message? Asked 12 years, 7 months ago Modified 1 year, 10 months ago Viewed 117k times When I press the button it will return the "Uncaught ReferenceError". One part of the problem is that "'React' is declared but its value is never read" is not a real error, it's because ts is configured to In the Node. This error can occur for a number of reasons, but it is usually due to a missing dependency. Why is Jest failing to load it? Also, this is supposed to be a default create-react-app test to check the App "renders Alternatively, if anyone experienced this bug had the problem wherein import React from 'react' is not necessary, because it is already included globally and doesn't need to be included in Summary I'm trying to test an API endpoint by testing its GET function, but when I run Jest, my test fails because Request is apparently not The jest global is only ever defined during tests. Learn why it occurs, how to fix it, and common FAQs. 16. lj13, ih5rx, jb, 1niu, jzjd97, x5zz, k1l, z6pji9, wxtftm, zxz, rt2eokp, gyj6, tt, xqflvy, gftuay, v4d, 3k9bj, ah, qj1, qkydop, w4t, vledj, in, kh, tyr, mnegw, ubfa, ydsno, rozd8, ls, \