PYTHON-4590 - Add type guards to async API methods

[NoahStapp]

No description provided.

[ShaneHarvey]

Do we need to do this? Doesn't the user already get an error if they pass in the wrong type? Could you give some examples?

[ShaneHarvey]

Could this ever be reached? Wouldn't something else fail beforehand?

[NoahStapp]

Do we need to do this? Doesn't the user already get an error if they pass in the wrong type? Could you give some examples?

The idea is that the current behavior looks like this:

>>> d = Database(AsyncMongoClient(), "test")
>>> d.list_collections()
<coroutine object AsyncMongoClient._retryable_read at 0x103023c40>

This change gives us this:

>>> d = Database(AsyncMongoClient(), "test")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/nstapp/Github/mongo-python-driver/pymongo/synchronous/database.py", line 128, in __init__
    raise TypeError(f"MongoClient required but {client} is an instance of {type(client)}")
TypeError: MongoClient required but AsyncMongoClient(host=['localhost:27017'], document_class=dict, tz_aware=False, connect=True) is an instance of <class 'pymongo.asynchronous.mongo_client.AsyncMongoClient'>

[blink1073]

It looks like this is no longer used

[ShaneHarvey]

Do we need to include both the repr(client) and the type(client)? It could be safer to only add the type to avoid adding topology/hostname info into these errors.

[NoahStapp]

Good point, I think type(client) makes more sense in this instance.

[ShaneHarvey]

I'm paranoid this might break apps that Mock pymongo classes but it should be fine. Anything that's mocking should inherit from our base classes anyway (instead of trying to ducktype).

[NoahStapp]

Good point, we'll have to watch out for bug reports with this.

[ShaneHarvey]

We should make the same {client} error message change to all the Database ones as well since Database's repr includes the client.