Typehinting with quotes generates warnings

[komjera]

Apache Airflow version

3.1.7

If "Other Airflow 3 version" selected, which one?

No response

What happened?

Received warning

Cannot infer multiple_outputs for TaskFlow function 'dataframe_task' with forward type references that are not imported. (Error was name 'DataFrame' is not defined) category=UserWarning

when using quotes when typehinting with a type that is only imported during TYPE_CHECKING.

What you think should happen instead?

There should be no warning

How to reproduce

from typing import TYPE_CHECKING

from airflow.sdk import dag, task

if TYPE_CHECKING:
    from pandas import DataFrame


@task(task_id="df_task")
def dataframe_task() -> "DataFrame":
    import pandas as pd

    df = pd.DataFrame({"a": [1, 2, 3]})
    return df


@dag()
def simple_dag():
    _ = dataframe_task()


simple_dag()

Operating System

Debian GNU/Linux 12 (bookworm)

Versions of Apache Airflow Providers

apache-airflow-providers-standard==1.11.0
apache-airflow-providers-common-sql==1.30.4
apache-airflow-providers-microsoft-azure==12.10.3
apache-airflow-providers-microsoft-mssql==4.4.1

Deployment

Astronomer

Deployment details

Running locally using astro CLI and image astrocrpublic.azurecr.io/runtime:3.1-13-python-3.12

Anything else?

No response

Are you willing to submit PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct

[boring-cyborg]

Thanks for opening your first issue here! Be sure to follow the issue template! If you are willing to raise PR to address this issue please do so, no need to wait for approval.

[jroachgolf84]

I'd like to go through and try to reproduce this. Before I do, was this working in a previous version of Airflow?

[komjera]

@jroachgolf84 In Airflow 2.11.0 and versions before that the example doesn't produce warnings.

Please let me know if you want me to do any further testing or if I can assist in some other way. I don't feel confident enough in Python to submit a PR unfortunately.