Tests are running against a valid api endpoint (that is hidden from us).
What you have to do :

1. call the Fetch api method using parameter (apiUrl)
2. this function will return the object which has 2 properties. And these properties have function definition (logic to get the jokeounch line...)
3. real api call is hidden from us, so you have to visualize the data using data sample given to us.

A useful link :
https://reactjs.org/docs/higher-order-components.html#use-hocs-for-cross-cutting-concerns

I don't understand what exactly I'm supposed to be returning. I am able to get the result and isolate the correct joke but I don't know what to return nor do I understand the error message I am getting.

The instructions say:

"When you got the joke it should be accessible through a simple API of saySetup and sayPunchLine methods."

Can an example of what a correct return message would look like be posted? I am able to get the return object and find the correct joke but what exactly am I supposed to return?

I have similar questions regarding the error case as well but can't address those till I can solve the above.

What does it mean 'use mock fetch(url)'? Should I mock it myself or use real fetch()?

API URL http://great.jokes/christmas is not reachable.

Old school React class components! Well, that was fun... in a way. Firstly I rewrited everything to functions and hooks, but it turned out the test env does not know what React.useState is. Rewrited everything back again. But enjoyed it nevertheless.

The kata's spec is very confusing: beaming people are supposed to be held in the inTransit properties. But then beaming 3 people should have them all beamed at once? Then what's the purpose of inTransit properties? They are supposed as a temporary storage, which means they shouldn't be tested (not to mention in reality it's not something that's actually needed).

As mentioned below, poor kata design.

The user's already solved the kata.

When you got the joke it should be accessible through a simple API of saySetup and sayPunchLine methods.

Post your code in a comment with a spoiler tag. Nobody will be able to help you if all you say is "something's wrong".

random tests fail. I don't understand I return exacly the message required by ID. and yet expected is som erandomly chosen value? can you descrive what you expect in random tests? tacked my brain for half a day already. thanks. adding this to description would also help.

The task points to the recommendation of avoiding indexes in keys and yet tests exactly that.
Why not using egg names instead of index for keys?
Still thanks for the kata!

the most legible solution I've reviewed so far; great work!