[eric] tests: the suite can never resume real chats with live credentials (ENG-388)

backend/apps/agents/manager/session/SessionPersistence.py

@@ -4,6 +4,7 @@ on boot). Split from SessionLifecycle (which handles ONE session at a time) so e
 one concern. self.sessions resolves across the MRO as before."""
 
 import logging
+import sys
 
 from typeguard import typechecked
 
@@ -18,6 +19,13 @@ from backend.apps.agents.manager.session.apply_context_window import apply_conte
 logger = logging.getLogger(__name__)
 
 
+def running_under_test() -> bool:
+    """Auto-resume dispatches REAL turns: live credentials, live Bash, in whatever tree the process
+    was started from. A test that boots the app lifespan must never do that to the developer's own
+    chats, so this is the one gate that keeps a suite run from becoming an agent run."""
+    return "pytest" in sys.modules
+
+
 from backend.apps.agents.manager.AgentManagerProtocol import AgentManagerProtocol
 
 
@@ -80,6 +88,10 @@ class SessionPersistence(AgentManagerProtocol):
         """Fire one hidden continuation into each crash-interrupted session (called after
         restore, off the boot critical path). Failure is per-session and non-fatal: a session
         that cannot resume just keeps its amber chip."""
+        if running_under_test():
+            logger.info("crash-resume: skipped, running under test")
+            self.crash_resume_queue = []
+            return
         for sid in list(getattr(self, "crash_resume_queue", []) or []):
             try:
                 # send_message lives on the Messaging mixin; AgentManager composes both.

backend/tests/test_crash_auto_resume.py

@@ -58,6 +58,13 @@ def test_second_consecutive_crash_trips_the_breaker(manager, tmp_path, monkeypat
         assert json.load(f)["crash_interrupt_count"] == 2
 
 
+def p_act_like_a_real_app(monkeypatch) -> None:
+    """Auto-resume refuses to dispatch under pytest, because it sends REAL turns and the suite shares
+    the developer's data root (ENG-388). These tests are about the production path, so they opt out."""
+    import backend.apps.agents.manager.session.SessionPersistence as p_sp
+    monkeypatch.setattr(p_sp, "running_under_test", lambda: False)
+
+
 def test_waiting_approval_never_auto_resumes(manager, tmp_path, monkeypatch):
     p_write_session(tmp_path, monkeypatch, "s-appr", "waiting_approval", [p_msg("user"), p_msg("tool_call")])
     asyncio.run(manager.reconcile_on_startup())
@@ -65,6 +72,7 @@ def test_waiting_approval_never_auto_resumes(manager, tmp_path, monkeypatch):
 
 
 def test_auto_resume_sends_one_hidden_continuation(manager, tmp_path, monkeypatch):
+    p_act_like_a_real_app(monkeypatch)
     p_write_session(tmp_path, monkeypatch, "s-cut", "running", [p_msg("user"), p_msg("tool_call")])
     asyncio.run(manager.reconcile_on_startup())
     sent = []
@@ -81,6 +89,7 @@ def test_auto_resume_sends_one_hidden_continuation(manager, tmp_path, monkeypatc
 
 
 def test_resume_failure_is_per_session_and_non_fatal(manager, tmp_path, monkeypatch):
+    p_act_like_a_real_app(monkeypatch)
     p_write_session(tmp_path, monkeypatch, "s-a", "running", [p_msg("user"), p_msg("tool_call")])
     p_write_session(tmp_path, monkeypatch, "s-b", "running", [p_msg("user"), p_msg("tool_call")])
     asyncio.run(manager.reconcile_on_startup())

backend/tests/test_no_real_turns_under_test.py

@@ -0,0 +1,49 @@
+"""A test run must never become an agent run.
+
+The bug class (caught live 2026-08-21): `agents_lifespan` fires `auto_resume_crashed_turns()`, which
+sends a real hidden continuation into every crash-interrupted session. The suite does not isolate the
+data root, so any test that boots the app lifespan resumed the DEVELOPER'S OWN chats with live
+credentials and live Bash, inside whatever tree the suite was running from. Observed: a full
+`pytest backend/tests` run spawned two real CLI processes which each started their own
+`pytest backend/tests/` run, because that was the task those chats had been interrupted mid-way
+through. It spends real money, rewrites real session files, and executes commands from old
+conversations against the working tree.
+
+The seal: auto-resume refuses to dispatch when pytest is loaded.
+"""
+
+import asyncio
+
+import backend.apps.agents.manager.session.SessionPersistence as p_sp
+from backend.apps.agents.agent_manager import agent_manager
+
+
+def p_capture_sends(monkeypatch) -> list:
+    sent: list = []
+
+    async def fake_send(session_id, prompt, hidden=False, **kwargs):
+        sent.append(session_id)
+
+    monkeypatch.setattr(agent_manager, "send_message", fake_send)
+    agent_manager.crash_resume_queue = ["sid-a", "sid-b"]
+    return sent
+
+
+def test_auto_resume_never_dispatches_under_test(monkeypatch):
+    sent = p_capture_sends(monkeypatch)
+    asyncio.run(agent_manager.auto_resume_crashed_turns())
+    assert sent == [], "a suite run must not spend credentials resuming real chats"
+    assert agent_manager.crash_resume_queue == [], "the queue is still cleared, so nothing resumes later either"
+
+
+def test_the_gate_is_what_stops_it(monkeypatch):
+    """Control: with the gate reporting a normal app process, the very same call does dispatch.
+    Without this arm the test above passes even if auto-resume quietly stopped working."""
+    sent = p_capture_sends(monkeypatch)
+    monkeypatch.setattr(p_sp, "running_under_test", lambda: False)
+    asyncio.run(agent_manager.auto_resume_crashed_turns())
+    assert sent == ["sid-a", "sid-b"]
+
+
+def test_the_gate_sees_pytest():
+    assert p_sp.running_under_test() is True