Fix: ensure bool(check_query_exists) returns True or False

[johncmerfeld]

closes: #43977

---

It is possible for bool(check_query_exists) to return None. This can break Xcom Jinja templates that retrieve null values from the airflow database using a LazySelectSequence

[boring-cyborg]

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[potiuk]

Could you please add a unit test covering this case?

[johncmerfeld]

Could you please add a unit test covering this case?

I'd love to; I'm just a little unsure where it would go. I couldn't find any module that tests the behavior of LazySelectSequence directly. I'd appreciate any advice you have on this!

[potiuk]

Could you please add a unit test covering this case?

I'd love to; I'm just a little unsure where it would go. I couldn't find any module that tests the behavior of LazySelectSequence directly. I'd appreciate any advice you have on this!

Maybe add one then - following the same structure in tests as you have for the source

[Copilot]

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 suggestion.

[johncmerfeld]

Maybe add one then - following the same structure in tests as you have for the source

Sure. Since it's an abstract class, I'm thinking I'll have to create a mock implementation for the test. I'll also need to mock check_query_exists so that it returns None .Something like:

class LazySelectSequenceInstance(LazySelectSequence[Any]):
    ... # implement required methods

@mock.patch("check_query_exists", lambda x, y: None):
def test_lazy_select_sequence():
    lss = LazySelectSequenceInstance(...)
    assert bool(lss) == False

Does this make sense?

[Lee-W]

Maybe add one then - following the same structure in tests as you have for the source

Sure. Since it's an abstract class, I'm thinking I'll have to create a mock implementation for the test. I'll also need to mock check_query_exists so that it returns None .Something like:

class LazySelectSequenceInstance(LazySelectSequence[Any]):
    ... # implement required methods

@mock.patch("check_query_exists", lambda x, y: None):
def test_lazy_select_sequence():
    lss = LazySelectSequenceInstance(...)
    assert bool(lss) == False

Does this make sense?

Sounds reasonable. We already have a mock class here

airflow/tests/serialization/test_serialized_objects.py

Line 170 in f5abe50

class MockLazySelectSequence(LazySelectSequence):

probably we could do something similar here as well?

[johncmerfeld]

@Lee-W I'm struggling to get unit tests running locally with virtualenv but all the CI checks appear to be passing.

EDIT: Ahh okay I see the tests don't actually run until there is an approval. Alas I'm unable to run the tests when building locally on MacOS or ubuntu. Not sure I have the hardware needed to run the docker version of the tests

[Lee-W]

@Lee-W I'm struggling to get unit tests running locally with virtualenv but all the CI checks appear to be passing.

EDIT: Ahh okay I see the tests don't actually run until there is an approval. Alas I'm unable to run the tests when building locally on MacOS or ubuntu. Not sure I have the hardware needed to run the docker version of the tests

for local test https://github.com/apache/airflow/blob/main/dev/breeze/doc/README.rst is the thing you might want to try 🙂

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.

[github-actions]

Backport failed to create: v2-10-test. View the failure log Run details

Status	Branch	Result
❌	v2-10-test

You can attempt to backport this manually by running:

cherry_picker 8d6bde8 v2-10-test

This should apply the commit to the v2-10-test branch and leave the commit in conflict state marking
the files that need manual conflict resolution.

After you have resolved the conflicts, you can continue the backport process by running:

cherry_picker --continue

[johncmerfeld]

@Lee-W I see this change is in main but is there a reason it hasn't been released in 2.10.4 or 2.10.5? Did I neglect to do something? Thanks!

[Lee-W]

hmmm.. not quite sure, but I can take a look

[Lee-W]

@johncmerfeld I guess it was due to conflict. Created backport PR #46707

[johncmerfeld]

I appreciate it @Lee-W - looks like that backport PR was successful so I will assume this change will be in the 2.10.6 release. Thanks!!