feat(memory): add incremental transcript compaction

tests/unit/memory/test_step_memory_service.py

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+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Unit tests for the shared StepMemoryService scheduling runtime (M1)."""
+
+import asyncio
+from unittest.mock import Mock
+
+import pytest
+
+from artemis.memory.step_memory import StepMemoryService
+
+
+class _ScriptedService(StepMemoryService):
+    """StepMemoryService with a scriptable attempt function and status log."""
+
+    def __init__(self, attempt_fn, **kwargs):
+        super().__init__(Mock(), **kwargs)
+        self._attempt_fn = attempt_fn
+        self.status_events: list[tuple] = []
+
+    async def _attempt(self, key):
+        return await self._attempt_fn(self, key)
+
+    def _on_status(self, key, status):
+        self.status_events.append((key, status))
+
+
+@pytest.mark.asyncio
+async def test_zero_blocking_submit_and_flush():
+    """submit() returns immediately; flush() drains the background job."""
+    release = asyncio.Event()
+
+    async def attempt(svc, key):
+        await release.wait()
+        svc._summaries[key] = f"summary-for-{key}"
+        return True
+
+    service = _ScriptedService(attempt)
+    service.submit("step-1", {"step_number": 1})
+
+    # Zero-blocking: the job cannot have completed yet (its gate is closed).
+    assert service.is_pending("step-1")
+    assert not service.has_summary("step-1")
+
+    release.set()
+    await service.flush()
+
+    assert service.get_summary("step-1") == "summary-for-step-1"
+    assert not service.is_pending("step-1")
+
+
+@pytest.mark.asyncio
+async def test_bounded_retry_enters_failed_state():
+    """A permanently failing job stops after 1 + retry_limit attempts."""
+    attempts = 0
+
+    async def attempt(svc, key):
+        nonlocal attempts
+        attempts += 1
+        return False
+
+    service = _ScriptedService(attempt, retry_limit=2)
+    service._retry_delays = (0.0,)
+    service.submit("step-x", {"step_number": 7})
+    await service.flush()
+
+    assert attempts == 3
+    assert service.has_failed("step-x")
+    assert not service.has_summary("step-x")
+    # The failed job still reads as pending (lossless semantics downstream).
+    assert service.is_pending("step-x")
+    assert service.status_events == [("step-x", "pending"), ("step-x", "failed")]
+
+
+@pytest.mark.asyncio
+async def test_step_id_keying_with_tool_call_alias():
+    """Jobs keyed by step id remain queryable through tool_call_id aliases."""
+
+    async def attempt(svc, key):
+        svc._summaries[key] = "canonical summary"
+        return True
+
+    service = _ScriptedService(attempt)
+    service.submit("uuid-123", {"step_number": 4}, aliases=("tc-abc",))
+    await service.flush()
+
+    assert service.resolve_key("tc-abc") == "uuid-123"
+    assert service.has_job("tc-abc")
+    assert service.has_summary("tc-abc")
+    assert service.get_summary("tc-abc") == "canonical summary"
+    assert service.get_summary("uuid-123") == "canonical summary"
+    assert service.get_job_payload("tc-abc") == {"step_number": 4}
+    assert not service.has_failed("tc-abc")
+
+
+@pytest.mark.asyncio
+async def test_max_concurrency_bounds_parallel_attempts():
+    """With max_concurrency=1, two jobs never run their attempts concurrently."""
+    active = 0
+    max_active = 0
+
+    async def attempt(svc, key):
+        nonlocal active, max_active
+        active += 1
+        max_active = max(max_active, active)
+        await asyncio.sleep(0.01)
+        active -= 1
+        svc._summaries[key] = "done"
+        return True
+
+    service = _ScriptedService(attempt, max_concurrency=1)
+    service.submit("a", {"step_number": 1})
+    service.submit("b", {"step_number": 2})
+    await service.flush()
+
+    assert service.has_summary("a") and service.has_summary("b")
+    assert max_active == 1
+
+
+@pytest.mark.asyncio
+async def test_flush_timeout_cancels_stragglers():
+    """flush() cancels jobs that outlive the timeout without failing them."""
+
+    async def attempt(svc, key):
+        await asyncio.sleep(30)
+        return True
+
+    service = _ScriptedService(attempt)
+    service.submit("slow", {"step_number": 1})
+    await service.flush(timeout_seconds=0.05)
+
+    assert service.is_pending("slow")
+    assert not service.has_failed("slow")
+    assert service._pending_tasks["slow"].done()
+
+
+@pytest.mark.asyncio
+async def test_flush_uses_configured_default_timeout():
+    """flush() with no argument honors the constructor's flush_timeout_s."""
+
+    async def attempt(svc, key):
+        await asyncio.sleep(30)
+        return True
+
+    service = _ScriptedService(attempt, flush_timeout_s=0.05)
+    service.submit("slow", {"step_number": 1})
+    await asyncio.wait_for(service.flush(), timeout=5)
+
+    assert service._pending_tasks["slow"].done()
+
+
+@pytest.mark.asyncio
+async def test_resubmit_clears_failed_state():
+    """Re-submitting a failed job gives it a fresh retry budget."""
+    behaviors = {"fail": True}
+
+    async def attempt(svc, key):
+        if behaviors["fail"]:
+            return False
+        svc._summaries[key] = "second time lucky"
+        return True
+
+    service = _ScriptedService(attempt, retry_limit=0)
+    service._retry_delays = (0.0,)
+    service.submit("job", {"step_number": 1})
+    await service.flush()
+    assert service.has_failed("job")
+
+    behaviors["fail"] = False
+    service._retry_counts.clear()
+    service.submit("job", {"step_number": 1})
+    await service.flush()
+
+    assert not service.has_failed("job")
+    assert service.get_summary("job") == "second time lucky"