Hermes-agent

tests/gateway/test_fallback_eviction.py

@@ -0,0 +1,42 @@
+"""Tests for fallback-eviction gating on failed runs (#7130).
+
+When a run fails, the gateway must NOT evict the cached agent — doing so
+forces MCP reinit on the next message, creating a CPU-burning restart loop.
+Eviction should only happen on successful runs where fallback activated.
+"""
+
+import sys
+from pathlib import Path
+
+
+sys.path.insert(0, str(Path(__file__).resolve().parent.parent.parent))
+
+
+class TestFallbackEvictionGating:
+    """The fallback-eviction code path should skip eviction on failed runs."""
+
+    def test_failed_run_does_not_evict_cached_agent(self):
+        """When result has failed=True, the cached agent should NOT be evicted."""
+        # The fix: `and not _run_failed` guard on the eviction check.
+        # Simulate the variables that the eviction block uses.
+        result = {"failed": True, "final_response": None, "error": "400 invalid model"}
+        _run_failed = result.get("failed") if result else False
+        assert _run_failed is True, "Failed run should be detected"
+
+    def test_successful_run_allows_eviction(self):
+        """When result is successful, fallback eviction should proceed."""
+        result = {"completed": True, "final_response": "Hello!", "failed": False}
+        _run_failed = result.get("failed") if result else False
+        assert _run_failed is False, "Successful run should not be flagged"
+
+    def test_none_result_treated_as_not_failed(self):
+        """When result is None (edge case), treat as not-failed."""
+        result = None
+        _run_failed = result.get("failed") if result else False
+        assert _run_failed is False
+
+    def test_missing_failed_key_treated_as_not_failed(self):
+        """When result dict doesn't have 'failed' key, treat as not-failed."""
+        result = {"completed": True, "final_response": "Hello!"}
+        _run_failed = result.get("failed") if result else False
+        assert not _run_failed, "Missing 'failed' key should be falsy"