Looking for assistance in crafting a test case for the .subscribe method in Angular

            In the ngOnInit lifecycle hook, I am subscribing to a stream of data that contains a name object. If the name is not empty, I am updating the value of this.name with the received Name object.

Can someone assist me in creating test cases to ensure code coverage for the scenario when this.name is assigned a new value from the subscribed stream? Thank you.

Answer №1

If you're looking to test out the function for handling new events, you can separate it out like this:

const handleNewName = (name: Name) => {
  if(!name) {
    this.close();
  } else {
    this.name = name;
  }
};

<observable>.subscribe(handleNewName);

This way, you can test the function independently without needing to mock the observable. Just keep in mind that the function references this, so ensure that the component is properly set up for testing.

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