test: add regression tests for #874 and #894 (#901)

Add tests for None event_date in fact extraction (AttributeError fix)
and for _register_profile skipping .env overwrite with short config keys.

hindsight-api-slim/tests/test_fact_extraction_retry.py

@@ -139,3 +139,76 @@ async def test_retain_llm_max_retries_overrides_global():
     assert facts == []
     # Verify it retried exactly retain_llm_max_retries times
     assert llm_config.call.call_count == 5
+
+
+@pytest.mark.asyncio
+async def test_none_event_date_with_empty_facts_no_crash():
+    """
+    When event_date is None and the LLM returns an empty facts list,
+    the debug log should not crash with AttributeError on .isoformat().
+
+    Regression test for https://github.com/vectorize-io/hindsight/issues/874
+    """
+    from hindsight_api.engine.retain.fact_extraction import _extract_facts_from_chunk
+
+    config = _make_config(llm_max_retries=1)
+
+    # LLM returns a valid dict but with no facts — triggers the debug log path
+    llm_config = _make_llm_config(mock_response={"facts": []})
+
+    with patch(
+        "hindsight_api.engine.retain.fact_extraction._build_extraction_prompt_and_schema",
+        return_value=("system prompt", MagicMock()),
+    ):
+        facts, usage = await _extract_facts_from_chunk(
+            chunk="A plain text document with no timestamp.",
+            chunk_index=0,
+            total_chunks=1,
+            event_date=None,
+            context="",
+            llm_config=llm_config,
+            config=config,
+            agent_name="test-agent",
+        )
+
+    assert facts == []
+
+
+@pytest.mark.asyncio
+async def test_none_event_date_with_valid_facts_no_crash():
+    """
+    When event_date is None but the LLM returns valid facts,
+    extraction should succeed without errors.
+    """
+    from hindsight_api.engine.retain.fact_extraction import _extract_facts_from_chunk
+
+    config = _make_config(llm_max_retries=1)
+
+    llm_config = _make_llm_config(mock_response={
+        "facts": [
+            {
+                "what": "Alice visited Paris",
+                "when": "2023",
+                "who": "Alice",
+                "why": "vacation",
+            }
+        ]
+    })
+
+    with patch(
+        "hindsight_api.engine.retain.fact_extraction._build_extraction_prompt_and_schema",
+        return_value=("system prompt", MagicMock()),
+    ):
+        facts, usage = await _extract_facts_from_chunk(
+            chunk="Alice visited Paris in 2023.",
+            chunk_index=0,
+            total_chunks=1,
+            event_date=None,
+            context="",
+            llm_config=llm_config,
+            config=config,
+            agent_name="test-agent",
+        )
+
+    assert len(facts) == 1
+    assert "Alice visited Paris" in facts[0].fact

hindsight-embed/tests/test_embed_manager.py

@@ -1,6 +1,9 @@
 """Tests for EmbedManager interface."""
 
+from unittest.mock import MagicMock
+
 from hindsight_embed import get_embed_manager
+from hindsight_embed.daemon_embed_manager import DaemonEmbedManager
 
 
 def test_sanitize_profile_name_via_db_url():
@@ -51,3 +54,43 @@ def test_manager_singleton():
 
     # They should produce the same results
     assert manager1.get_database_url("test") == manager2.get_database_url("test")
+
+
+def test_register_profile_skips_when_no_api_keys():
+    """
+    When config contains only short keys (no HINDSIGHT_API_* prefix),
+    _register_profile should not call create_profile, preserving any
+    existing profile .env file.
+
+    Regression test for https://github.com/vectorize-io/hindsight/issues/894
+    """
+    manager = DaemonEmbedManager()
+    manager._profile_manager = MagicMock()
+
+    # Config with short keys (as passed from cli.py's get_config())
+    config = {"llm_api_key": "sk-123", "llm_provider": "openai", "llm_model": "gpt-4o"}
+    manager._register_profile("myprofile", 8100, config)
+
+    manager._profile_manager.create_profile.assert_not_called()
+
+
+def test_register_profile_calls_create_when_api_keys_present():
+    """
+    When config contains HINDSIGHT_API_* keys, _register_profile should
+    forward them to create_profile.
+    """
+    manager = DaemonEmbedManager()
+    manager._profile_manager = MagicMock()
+
+    config = {
+        "HINDSIGHT_API_LLM_PROVIDER": "openai",
+        "HINDSIGHT_API_LLM_API_KEY": "sk-123",
+        "some_internal_key": "ignored",
+    }
+    manager._register_profile("myprofile", 8100, config)
+
+    manager._profile_manager.create_profile.assert_called_once_with(
+        "myprofile",
+        8100,
+        {"HINDSIGHT_API_LLM_PROVIDER": "openai", "HINDSIGHT_API_LLM_API_KEY": "sk-123"},
+    )