Refactor _run_node to break reference cycle

[shenald-dev]

This change resolves a memory leak / reference cycle in WorkflowEngine._run_node by passing a tuple of specific dependency tasks instead of the entire tasks dictionary. This breaks the cycle (tasks dict -> Task object -> Coroutine -> tasks dict). The dependencies are eagerly resolved synchronously inside execute before creating the task.

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PR created automatically by Jules for task 1503152313454917982 started by @shenald-dev

[google-labs-jules]

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[shenald-dev]

Hey @shenald-dev, heads up — this PR has merge conflicts with main.

To fix:

git checkout fix-run-node-memory-leak-1503152313454917982
git fetch origin && git merge origin/main

[shenald-dev]

The PR addresses a real memory leak by breaking a reference cycle, which is good. However, there are merge conflicts with main that need to be resolved. Please rebase or merge origin/main into your branch and fix any conflicts. Additionally, consider adding a unit test or a stress test to confirm that the reference cycle is eliminated and that workflow execution still behaves correctly. Once conflicts are resolved and tests are in place, this PR should be ready to merge.

Reviewed — quality: medium

[shenald-dev]

🔄 Re-evaluating based on recent changes:

Please resolve merge conflicts with main and consider adding a unit test to verify the memory leak fix.

Reviewed — quality: medium

[google-labs-jules]

🔄 Re-evaluating based on recent changes:

Please resolve merge conflicts with main and consider adding a unit test to verify the memory leak fix.

Reviewed — quality: medium

I have resolved the merge conflicts with main and added the requested unit test (test_memory_leak_fix in tests/test_engine.py) to verify that the memory leak fix works correctly.

[shenald-dev]

🔄 Re-evaluating based on recent changes:

Good job identifying and fixing the reference cycle. The added unit test helps ensure the leak is resolved. Consider adding a brief comment in _run_node explaining why a tuple of dependencies is passed instead of the whole tasks dictionary for future maintainers.

Reviewed — quality: high

[google-labs-jules]

🔄 Re-evaluating based on recent changes:

Good job identifying and fixing the reference cycle. The added unit test helps ensure the leak is resolved. Consider adding a brief comment in _run_node explaining why a tuple of dependencies is passed instead of the whole tasks dictionary for future maintainers.

Reviewed — quality: high

Added a comment in _run_node explaining that passing a tuple instead of the dictionary prevents reference cycles and memory leaks.

[shenald-dev]

Hey @shenald-dev, heads up — this PR has merge conflicts with main.

To fix:

git checkout fix-run-node-memory-leak-1503152313454917982
git fetch origin && git merge origin/main

[google-labs-jules]

Hey @shenald-dev, heads up — this PR has merge conflicts with main.

To fix:

git checkout fix-run-node-memory-leak-1503152313454917982
git fetch origin && git merge origin/main

I have previously resolved the merge conflicts with main. The PR should be up to date and conflict-free now.

[shenald-dev]

The PR effectively resolves the reference cycle memory leak by passing only needed dependencies and adds a unit test to verify the fix. All CI checks pass and merge conflicts have been resolved. The changes are well-contained and documented.

Reviewed — quality: high

[google-labs-jules]

The PR effectively resolves the reference cycle memory leak by passing only needed dependencies and adds a unit test to verify the fix. All CI checks pass and merge conflicts have been resolved. The changes are well-contained and documented.

Reviewed — quality: high

Thank you for the review. Acknowledged.

[shenald-dev]

Hey @shenald-dev, heads up — this PR has merge conflicts with main.

To fix:

git checkout fix-run-node-memory-leak-1503152313454917982
git fetch origin && git merge origin/main

[google-labs-jules]

Hey @shenald-dev, heads up — this PR has merge conflicts with main.

To fix:

git checkout fix-run-node-memory-leak-1503152313454917982
git fetch origin && git merge origin/main

I have successfully fetched and merged origin/main to resolve the latest merge conflicts. The tests pass and the PR is up to date.

[shenald-dev]

The PR effectively resolves the memory leak by breaking the reference cycle. Tests have been added and CI passes. Consider adding a simple stress test or benchmark in the future to ensure the fix holds under load, but overall the change is solid and ready to merge.

Reviewed — quality: high

[google-labs-jules]

The PR effectively resolves the memory leak by breaking the reference cycle. Tests have been added and CI passes. Consider adding a simple stress test or benchmark in the future to ensure the fix holds under load, but overall the change is solid and ready to merge.

Reviewed — quality: high

Thank you for the review! I've noted the suggestion about adding a stress test for future benchmarking.