feat: relationship-seed service for first-co-appearance prompt

tests/test_relationship_seed.py

@@ -0,0 +1,109 @@
+"""Tests for the relationship-seed service (T38).
+
+Per Requirements §5.2, when two bots first co-appear in a chat, the user
+is prompted with "Have they met before? If yes, write a short prose
+seed." The prose is parsed via classifier into structured directed-edge
+content for the ``botA -> botB`` and ``botB -> botA`` edges.
+
+These tests cover:
+
+* The happy path: a canned classifier response parses cleanly into a
+  populated :class:`RelationshipSeed` with both directions filled.
+* Empty prose short-circuits before any classifier call (mock has no
+  canned responses; an accidental call would raise ``IndexError``).
+* Whitespace-only prose has the same short-circuit behavior.
+"""
+
+from __future__ import annotations
+
+import json
+
+import pytest
+
+from chat.llm.mock import MockLLMClient
+from chat.services.relationship_seed import (
+    RelationshipSeed,
+    seed_inter_bot_edges,
+)
+
+
+@pytest.mark.asyncio
+async def test_seed_parses_canned_prose():
+    canned = json.dumps(
+        {
+            "a_to_b_summary": "old college friend who now distrusts him slightly",
+            "a_to_b_knowledge_facts": [
+                "studied physics together",
+                "lost touch after a falling out",
+            ],
+            "a_to_b_affinity_delta": 2,
+            "a_to_b_trust_delta": -1,
+            "b_to_a_summary": "former roommate; warm memories, mild resentment",
+            "b_to_a_knowledge_facts": ["lived together junior year"],
+            "b_to_a_affinity_delta": 3,
+            "b_to_a_trust_delta": 0,
+        }
+    )
+    mock = MockLLMClient(canned=[canned])
+    result = await seed_inter_bot_edges(
+        mock,
+        classifier_model="x",
+        bot_a_id="bot_a",
+        bot_a_name="Alice",
+        bot_b_id="bot_b",
+        bot_b_name="Bob",
+        relationship_prose=(
+            "Alice and Bob met in college. They studied physics together and "
+            "lived as roommates junior year, but drifted apart after a fight."
+        ),
+    )
+    assert isinstance(result, RelationshipSeed)
+    assert (
+        result.a_to_b_summary
+        == "old college friend who now distrusts him slightly"
+    )
+    assert result.a_to_b_knowledge_facts == [
+        "studied physics together",
+        "lost touch after a falling out",
+    ]
+    assert result.a_to_b_affinity_delta == 2
+    assert result.a_to_b_trust_delta == -1
+    assert (
+        result.b_to_a_summary
+        == "former roommate; warm memories, mild resentment"
+    )
+    assert result.b_to_a_knowledge_facts == ["lived together junior year"]
+    assert result.b_to_a_affinity_delta == 3
+    assert result.b_to_a_trust_delta == 0
+
+
+@pytest.mark.asyncio
+async def test_seed_empty_prose_returns_empty():
+    """Empty prose short-circuits — classifier must not be called."""
+    mock = MockLLMClient(canned=[])
+    result = await seed_inter_bot_edges(
+        mock,
+        classifier_model="x",
+        bot_a_id="bot_a",
+        bot_a_name="Alice",
+        bot_b_id="bot_b",
+        bot_b_name="Bob",
+        relationship_prose="",
+    )
+    assert result == RelationshipSeed()
+
+
+@pytest.mark.asyncio
+async def test_seed_whitespace_only_prose_returns_empty():
+    """Whitespace-only prose is treated the same as empty."""
+    mock = MockLLMClient(canned=[])
+    result = await seed_inter_bot_edges(
+        mock,
+        classifier_model="x",
+        bot_a_id="bot_a",
+        bot_a_name="Alice",
+        bot_b_id="bot_b",
+        bot_b_name="Bob",
+        relationship_prose="   \n  ",
+    )
+    assert result == RelationshipSeed()