evals/test_context_isolation.py

"""
Context-isolation eval — pure-function tests for the cross-agent
contamination guards added to agent_hub.py.

Verifies that:
  - _clear_foreign_agent_context drops only foreign-owned keys
  - Unknown keys (not in any agent's registry) are preserved
  - Keys owned by the kept agent survive
"""

import pytest

from app.ai.agent.agent_hub import _clear_foreign_agent_context
from evals.harness import load_cases, make_state


CASES = load_cases("context_isolation.yaml")


@pytest.mark.parametrize("case", CASES, ids=[c["id"] for c in CASES])
def test_clear_foreign_agent_context(case):
    state = make_state(agent_context=dict(case["agent_context_before"]))

    _clear_foreign_agent_context(state, keep_agent=case["keep_agent"])

    for key in case["expected_keys_present"]:
        assert key in state.agent_context, (
            f"Case {case['id']!r}: expected {key!r} preserved "
            f"(agent_context now: {list(state.agent_context.keys())})"
        )

    for key in case["expected_keys_removed"]:
        assert key not in state.agent_context, (
            f"Case {case['id']!r}: expected {key!r} removed "
            f"but still present in {list(state.agent_context.keys())}"
        )