Commit time and write results aren't set after the transaction is committed via decorated transactional function

[rostyq]

Currently, it is not possible to check transformation results after a successful transaction run in a decorated function without additional read access to firestore database.

Environment details

• OS type and version: Windows 11
• Python version: 3.12.0
• pip version: 24.1.1
• google-cloud-firestore version: 2.16.1

Steps to reproduce

1. Implement a @transactional (or @async_transactional) function using any firestore transforms (for example SERVER_TIMESTAMP)
2. Run a successful Transaction (or AsyncTransaction) in the decorated function
3. Access commit_time and write_results

Code example

from google.cloud.firestore_v1.client import Client
from google.cloud.firestore_v1.transaction import Transaction, transactional
from google.cloud.firestore_v1.transforms import SERVER_TIMESTAMP

client = Client()

@transactional
def run(t: Transaction):
    t.set(client.document("examples/example"), {"server_timestamp": SERVER_TIMESTAMP})

t = client.transaction()

run(t)

print(t.commit_time)
print(t.write_results)