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Tag: testing

Mocha test false assert timeouts

I have some problem with my async mocha tests. The assert method within a promise results in a timeout when the input evaluates to false. (with true values it works fine) This is a simplified version of the problem. We usually do networking instead of this constructed promise. Answer You’d better NOT us…

Console.log from a class’ function

I want to test if my function inside my class returns the given sentence. But if I try to test using console.log, it returns ReferenceError: rev is not defined. What am I doing wrong? I’m a fairly new programmer, so bear with me if this is a stupid question. Answer The entire point of a class is to prov…

How to test method called in promise

I have a function that saves an entity and in the promise i want to check the delete is called. In my jest test it whizzes past and can’t think how to test it Here is the partial snippets, it all works, Promises called etc. just can’t figure how to test that ‘deleteMessage’ is called I…

How to mock/spy useState hook in jest?

I am trying to spy on useState React hook but i always get the test failed This is my React component: counter.test.js: Unfortunately this doesn’t work and i get the test failed with that message: Answer You need to use React.useState instead of the single import useState. I think is about how the code …