claw-code/tests/test_submit_message_cancell...

221 lines
8.2 KiB
Python

"""Tests for cooperative cancellation in submit_message (ROADMAP #164 Stage A).
Verifies that cancel_event enables safe early termination:
- Event set before call => immediate return with stop_reason='cancelled'
- Event set between budget check and commit => still 'cancelled', no mutation
- Event set after commit => not observable (honest cooperative limit)
- Legacy callers (cancel_event=None) see zero behaviour change
- State is untouched on cancellation: mutable_messages, transcript_store,
permission_denials, total_usage all preserved
This closes the #161 follow-up gap filed as #164: wedged provider threads
can no longer silently commit ghost turns after the caller observed a
timeout.
"""
from __future__ import annotations
import sys
import threading
from pathlib import Path
sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
from src.models import PermissionDenial # noqa: E402
from src.port_manifest import build_port_manifest # noqa: E402
from src.query_engine import QueryEngineConfig, QueryEnginePort, TurnResult # noqa: E402
def _fresh_engine(**config_overrides) -> QueryEnginePort:
config = QueryEngineConfig(**config_overrides) if config_overrides else QueryEngineConfig()
return QueryEnginePort(manifest=build_port_manifest(), config=config)
class TestCancellationBeforeCall:
"""Event set before submit_message is invoked => immediate 'cancelled'."""
def test_pre_set_event_returns_cancelled_immediately(self) -> None:
engine = _fresh_engine()
event = threading.Event()
event.set()
result = engine.submit_message('hello', cancel_event=event)
assert result.stop_reason == 'cancelled'
assert result.prompt == 'hello'
# Output is empty on pre-budget cancel (no synthesis)
assert result.output == ''
def test_pre_set_event_preserves_mutable_messages(self) -> None:
engine = _fresh_engine()
event = threading.Event()
event.set()
engine.submit_message('ghost turn', cancel_event=event)
assert engine.mutable_messages == [], (
'cancelled turn must not appear in mutable_messages'
)
def test_pre_set_event_preserves_transcript_store(self) -> None:
engine = _fresh_engine()
event = threading.Event()
event.set()
engine.submit_message('ghost turn', cancel_event=event)
assert engine.transcript_store.entries == [], (
'cancelled turn must not appear in transcript_store'
)
def test_pre_set_event_preserves_usage_counters(self) -> None:
engine = _fresh_engine()
initial_usage = engine.total_usage
event = threading.Event()
event.set()
engine.submit_message('expensive prompt ' * 100, cancel_event=event)
assert engine.total_usage == initial_usage, (
'cancelled turn must not increment token counters'
)
def test_pre_set_event_preserves_permission_denials(self) -> None:
engine = _fresh_engine()
event = threading.Event()
event.set()
denials = (PermissionDenial(tool_name='BashTool', reason='destructive'),)
engine.submit_message('run bash ls', denied_tools=denials, cancel_event=event)
assert engine.permission_denials == [], (
'cancelled turn must not extend permission_denials'
)
class TestCancellationAfterBudgetCheck:
"""Event set between budget projection and commit => 'cancelled', state intact.
This simulates the realistic racy case: engine starts computing output,
caller hits deadline, sets event. Engine observes at post-budget checkpoint
and returns cleanly.
"""
def test_post_budget_cancel_returns_cancelled(self) -> None:
engine = _fresh_engine()
event = threading.Event()
# Patch: set the event after projection but before mutation. We do this
# by wrapping _format_output (called mid-submit) to set the event.
original_format = engine._format_output
def _set_then_format(*args, **kwargs):
result = original_format(*args, **kwargs)
event.set() # trigger cancel right after output is built
return result
engine._format_output = _set_then_format # type: ignore[method-assign]
result = engine.submit_message('hello', cancel_event=event)
assert result.stop_reason == 'cancelled'
# Output IS built here (we're past the pre-budget checkpoint), so it's
# not empty. The contract is about *state*, not output synthesis.
assert result.output != ''
# Critical: state still unchanged
assert engine.mutable_messages == []
assert engine.transcript_store.entries == []
class TestCancellationAfterCommit:
"""Event set after commit is not observable \u2014 honest cooperative limit."""
def test_post_commit_cancel_is_not_observable(self) -> None:
engine = _fresh_engine()
event = threading.Event()
# Event only set *after* submit_message returns. The first call has
# already committed before the event is set.
result = engine.submit_message('hello', cancel_event=event)
event.set() # too late
assert result.stop_reason == 'completed', (
'cancel set after commit must not retroactively invalidate the turn'
)
assert engine.mutable_messages == ['hello']
def test_next_call_observes_cancel(self) -> None:
"""The cancel_event persists \u2014 the next call on the same engine sees it."""
engine = _fresh_engine()
event = threading.Event()
engine.submit_message('first', cancel_event=event)
assert engine.mutable_messages == ['first']
event.set()
# Next call observes the cancel at entry
result = engine.submit_message('second', cancel_event=event)
assert result.stop_reason == 'cancelled'
# 'second' must NOT have been committed
assert engine.mutable_messages == ['first']
class TestLegacyCallersUnchanged:
"""cancel_event=None (default) => zero behaviour change from pre-#164."""
def test_no_event_submits_normally(self) -> None:
engine = _fresh_engine()
result = engine.submit_message('hello')
assert result.stop_reason == 'completed'
assert engine.mutable_messages == ['hello']
def test_no_event_with_budget_overflow_still_rejects_atomically(self) -> None:
"""#162 atomicity contract survives when cancel_event is absent."""
engine = _fresh_engine(max_budget_tokens=1)
words = ' '.join(['word'] * 100)
result = engine.submit_message(words) # no cancel_event
assert result.stop_reason == 'max_budget_reached'
assert engine.mutable_messages == []
def test_no_event_respects_max_turns(self) -> None:
"""max_turns_reached contract survives when cancel_event is absent."""
engine = _fresh_engine(max_turns=1)
engine.submit_message('first')
result = engine.submit_message('second') # no cancel_event
assert result.stop_reason == 'max_turns_reached'
assert engine.mutable_messages == ['first']
class TestCancellationVsOtherStopReasons:
"""cancel_event has a defined precedence relative to budget/turns."""
def test_cancel_precedes_max_turns_check(self) -> None:
"""If cancel is set when capacity is also full, cancel wins (clearer signal)."""
engine = _fresh_engine(max_turns=0) # immediately full
event = threading.Event()
event.set()
result = engine.submit_message('hello', cancel_event=event)
# cancel_event check is the very first thing in submit_message,
# so it fires before the max_turns check even sees capacity
assert result.stop_reason == 'cancelled'
def test_cancel_does_not_override_commit(self) -> None:
"""Completed turn with late cancel still reports 'completed' \u2014 the
turn already succeeded; we don't lie about it."""
engine = _fresh_engine()
event = threading.Event()
# Event gets set after the mutation is done \u2014 submit_message doesn't
# re-check after commit
result = engine.submit_message('hello', cancel_event=event)
event.set()
assert result.stop_reason == 'completed'