This suggestion type is supposed to use suggestion_models.TARGET_TYPE_TOPIC. Don't use the creation functions in the models directly (here and elsewhere). Create the models using the services (which does these checks automatically).

There is a service called create_suggestion in suggestion_services but that does not allow us to choose the thread id -- it creates one of its own, and we need the thread id to send the request(get_json, post_json etc). The only way to use the service would be to do self.swap but I was confused which was the better choice (creating the model or doing self.swap). Should I use self.swap instead then?

And why should the suggestion type necessarily has to be TARGET_TYPE_TOPIC. We are testing it with incorrect target type where the correct type is TARGET_TYPE_EXPLORATION. Hence any other types other than TARGET_TYPE_EXPLORATION should be fine, right?

The correct type here is TARGET_TYPE_TOPIC (see suggestion_registry). We have one controller for every type of target. So what you should be testing is that a valid suggestion, passed to the wrong controller should raise an error.

You could also get the thread ID by crafting a query to the suggestion list handler (an extra step, but prevents directly manipulating models. By directly adding models, we bypass the validations written in the domain/service layers).

Ah yes you are correct. Will fix this!

Done

test_reject_suggestion_to_topic maybe? Are we not testing the "accept" action? Though probably without that test too, the coverage might be a 100%, I would suggest adding a test for that too.

Done