Improve tests coverage

[networmix]

Summary

• add missing error checks in failure_policy
• add coverage for TrafficManager result summarization
• add invalid config test for CapacityProbe

Testing

• ruff check tests/test_failure_policy.py tests/test_traffic_manager.py tests/workflow/test_capacity_probe.py
• black --check tests/test_failure_policy.py tests/test_traffic_manager.py tests/workflow/test_capacity_probe.py
• isort --check tests/test_failure_policy.py tests/test_traffic_manager.py tests/workflow/test_capacity_probe.py
• pytest -q --cov=ngraph --cov-fail-under=85 --cov-report term-missing

[Copilot]

Pull Request Overview

This PR enhances test coverage by adding error handling checks and covering previously untested branches in key modules.

• Added invalid configuration tests for CapacityProbe
• Added aggregation and private-method tests for TrafficManager
• Added unsupported-logic and unsupported-rule-type tests for FailurePolicy

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
tests/workflow/test_capacity_probe.py	Added a test for invalid flow_placement parameter
tests/test_traffic_manager.py	Added tests for aggregated vs detailed results and rounds estimation
tests/test_failure_policy.py	Added tests for unsupported logic and rule types

Comments suppressed due to low confidence (1)

tests/workflow/test_capacity_probe.py:3

• The import statement has unnecessary leading whitespace; move it to column 1 to maintain consistent import formatting.

  import pytest

[Copilot]

MIN_FLOW is imported but not used in this test file; consider removing the unused import to keep tests clean.

Suggested change

from ngraph.lib.algorithms.base import MIN_FLOW

[Copilot]

[nitpick] Testing a private method (_estimate_rounds) can lead to brittle tests; consider verifying this behavior through the public API (e.g., using place_all_demands with known inputs).

Suggested change

	"""_estimate_rounds should compute rounds based on demand/capacity ratio."""
	demands = [TrafficDemand(source_path="A", sink_path="C", demand=20.0)]
	tm = TrafficManager(network=small_network, traffic_demands=demands)
	tm.build_graph()
	tm.expand_demands()
	assert tm._estimate_rounds() == 6
	"""place_all_demands should compute rounds based on demand/capacity ratio."""
	demands = [TrafficDemand(source_path="A", sink_path="C", demand=20.0)]
	tm = TrafficManager(network=small_network, traffic_demands=demands)
	tm.build_graph()
	tm.expand_demands()
	total_placed = tm.place_all_demands(placement_rounds="auto")
	# With demand=20.0 and capacity=100.0, 6 rounds are expected to place all demands.
	assert total_placed == 20.0, "All demands should be placed"
	assert tm.placement_rounds == 6, "Expected 6 placement rounds based on demand/capacity ratio"