All the examples of jest and jest-fetch-mock I have come across use functions that perform an API query and return a payload directly from the function call.
In my case, I have a different setup. I have a class that has a property called 'data'. In the class there is a method called "get" which pulls data using fetch API and stores it in the data property. When the method is called, it simply returns true or false based on promise resolve or reject.
I am trying to figure out how to write unit tests for this in this case. My function doesn't return the data fetched; only a boolean value.
So if I use jestSpyOn to mock the class method, how would I set the data property, and then retrieve the result?
In my code, I do something like this (NOT in testing, but in the actual app):
contactStore = new ContactListStore();
// 'all' is a sample param passed
contactStore.get('all').then(res => {
if(res){
...perform action
}
});
As you can see the res argument is only boolean, and if true, then contactStore.data will contain the information retrieved from the server.
So to run a unit test on it, I need to call a mock get, and set a mock data property.
Any ideas how this would be done?
