[Python] How to test Firebase Callable Function concurrency locally using Python and the...

I'm working with Firebase Functions (Python) and trying to test a Callable HTTPS function that performs a Firestore transaction. Here's a simplified version of the function:

@https_fn.on_call()
def increment(req: https_fn.CallableRequest) -> any:
db = firestore.client()
uid = req.auth.uid
transaction = db.transaction()
doc_ref = db.collection("numbers").document(uid)
result = function(transaction,doc_ref)

@firestore.transactional
def function(transaction , ref ):
doc = ref.get(transaction = transaction)
data = doc.to_dict()
if data.get('count') < 10:
transaction.update(ref, {'count': firestore.Increment(1)})

return True



What I’m Trying to Do:

I want to test this function locally using firebase emulator under concurrent access using unit tests.

Challenges:

1. There seems to be no official documentation for unit testing Firebase Functions in Python.
2. I'm not using standard HTTP functions — this is a Callable HTTPS function, which makes local invocation and concurrency testing a bit trickier since the invocation must happen from authenticated context .

Currently explored

1. unit testing(https://firebase.google.com/docs/functions/unit-testing): only found for JS.
2. interactive shell(https://firebase.google.com/docs/functions/local-shell) : not sure if I can create unit test like condition.

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