Fix mutable default argument in merge_logs_to_list

[juandiego-bmu]

Summary

Replace log_list=[] with log_list=None and initialize inside the function body.

The mutable default list was shared across all calls. Since it's mutated via .append() on line 41, log entries from previous invocations leak into subsequent results and the list grows without bound.

Split from #1466 as requested by @pUrGe12.

Fixes #1464

[coderabbitai]

Summary by CodeRabbit

• Chores
  • Code quality improvement to internal utilities—no user-facing changes.

Walkthrough

Fixes a mutable default argument bug in merge_logs_to_list by changing the default parameter from an empty list to None and initializing the list inside the function to prevent log contamination across calls.

Changes

Cohort / File(s)	Summary
Bug Fix nettacker/core/utils/common.py	Changed merge_logs_to_list function signature to use log_list=None as default parameter instead of log_list=[], with initialization logic added inside the function. Prevents mutable default argument anti-pattern that was causing log entries to persist across multiple function calls.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately summarizes the main change: fixing a mutable default argument in the merge_logs_to_list function, which is the exact focus of the changeset.
Description check	✅ Passed	The description clearly explains the bug (mutable default list being shared and mutated), its impact on log contamination, and the fix applied, all directly related to the changeset.
Linked Issues check	✅ Passed	The PR implements the exact fix suggested in issue #1464: replacing log_list=[] with log_list=None and initializing it inside the function body to prevent shared mutable state.
Out of Scope Changes check	✅ Passed	All changes are scoped to the merge_logs_to_list function signature and initialization logic, directly addressing the mutable default argument issue in #1464 with no extraneous modifications.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[Copilot]

Pull request overview

This PR fixes a Python mutable default argument bug in merge_logs_to_list, preventing log entries from leaking across calls and avoiding unbounded growth of a shared default list.

Changes:

• Change merge_logs_to_list(result, log_list=[]) to default log_list=None.
• Initialize log_list = [] inside the function when None is provided.

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[coderabbitai]

🧹 Nitpick comments (1)

nettacker/core/utils/common.py (1)

34-36: Consider adding type hints (and a short docstring) for this public utility.

This function is in a core shared utility path; typing the parameters/return improves readability and safer callsites.

♻️ Suggested refactor

-def merge_logs_to_list(result, log_list=None):
+def merge_logs_to_list(result: object, log_list: list[str] | None = None) -> list[str]:
+    """Collect and deduplicate nested `log` values from a result structure."""
     if log_list is None:
         log_list = []

As per coding guidelines, "Keep functions small, use type hints where practical, and add docstrings for public APIs".

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@nettacker/core/utils/common.py` around lines 34 - 36, Update
merge_logs_to_list to include type hints and a short docstring: annotate
parameters as result: Dict[str, Any] (or appropriate specific type) and
log_list: Optional[List[Dict[str, Any]]] = None, and the return type as
List[Dict[str, Any]]; add a one- or two-line docstring describing the function
purpose, parameters, and return value; ensure you import Optional, List, Dict,
Any from typing at the top and keep the existing None-default pattern to avoid
mutable defaults.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Nitpick comments:
In `@nettacker/core/utils/common.py`:
- Around line 34-36: Update merge_logs_to_list to include type hints and a short
docstring: annotate parameters as result: Dict[str, Any] (or appropriate
specific type) and log_list: Optional[List[Dict[str, Any]]] = None, and the
return type as List[Dict[str, Any]]; add a one- or two-line docstring describing
the function purpose, parameters, and return value; ensure you import Optional,
List, Dict, Any from typing at the top and keep the existing None-default
pattern to avoid mutable defaults.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: e2df119d-d3f1-4316-aa1c-c657e9978a33

📥 Commits

Reviewing files that changed from the base of the PR and between f4c1bbf and 90a6481.

📒 Files selected for processing (1)

• nettacker/core/utils/common.py

[juandiego-bmu]

Closing to recreate with proper PR template and signed commits as requested.