235 lines
10 KiB
Python
235 lines
10 KiB
Python
"""Regression tests for cursor recovery after non-integer cursor corruption.
|
|
|
|
Root cause: cron jobs and other callers occasionally wrote string cursors to
|
|
history.jsonl (e.g. ``"cursor": "abc"``). The original ``_next_cursor`` and
|
|
``read_unprocessed_history`` assumed integer cursors and crashed with
|
|
``TypeError`` / ``ValueError``, blocking all subsequent history appends.
|
|
"""
|
|
|
|
import pytest
|
|
|
|
from nanobot.agent.memory import MemoryStore
|
|
|
|
|
|
@pytest.fixture
|
|
def store(tmp_path):
|
|
return MemoryStore(tmp_path)
|
|
|
|
|
|
class TestNextCursorRecovery:
|
|
"""``_next_cursor`` must recover a valid int even when the last entry's
|
|
cursor is corrupted (non-int)."""
|
|
|
|
def test_string_cursor_falls_back_to_scan(self, store):
|
|
"""Last entry has a string cursor — scan backwards to find a valid int."""
|
|
store.history_file.write_text(
|
|
'{"cursor": 5, "timestamp": "2026-04-01 10:00", "content": "good"}\n'
|
|
'{"cursor": 6, "timestamp": "2026-04-01 10:01", "content": "also good"}\n'
|
|
'{"cursor": "bad", "timestamp": "2026-04-01 10:02", "content": "corrupted"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
# Delete .cursor file so _next_cursor falls back to reading JSONL
|
|
store._cursor_file.unlink(missing_ok=True)
|
|
cursor = store.append_history("recovered event")
|
|
assert cursor == 7
|
|
|
|
def test_all_corrupted_cursors_return_one(self, store):
|
|
"""Every entry has a non-int cursor — should restart at 1."""
|
|
store.history_file.write_text(
|
|
'{"cursor": "a", "timestamp": "2026-04-01 10:00", "content": "bad1"}\n'
|
|
'{"cursor": "b", "timestamp": "2026-04-01 10:01", "content": "bad2"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
store._cursor_file.unlink(missing_ok=True)
|
|
cursor = store.append_history("fresh start")
|
|
assert cursor == 1
|
|
|
|
def test_non_int_cursor_types(self, store):
|
|
"""Float, None, list — all non-int types handled gracefully."""
|
|
store.history_file.write_text(
|
|
'{"cursor": 3, "timestamp": "2026-04-01 10:00", "content": "valid"}\n'
|
|
'{"cursor": 3.5, "timestamp": "2026-04-01 10:01", "content": "float"}\n'
|
|
'{"cursor": null, "timestamp": "2026-04-01 10:02", "content": "null"}\n'
|
|
'{"cursor": [1,2], "timestamp": "2026-04-01 10:03", "content": "list"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
store._cursor_file.unlink(missing_ok=True)
|
|
cursor = store.append_history("handles weird types")
|
|
assert cursor == 4
|
|
|
|
def test_cursor_file_with_string_content(self, store):
|
|
"""Cursor file contains a non-numeric string — should fall back."""
|
|
store._cursor_file.write_text("not_a_number", encoding="utf-8")
|
|
# Also add valid JSONL so the fallback scan finds something
|
|
store.history_file.write_text(
|
|
'{"cursor": 10, "timestamp": "2026-04-01 10:00", "content": "valid"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
cursor = store.append_history("after bad cursor file")
|
|
assert cursor == 11
|
|
|
|
def test_stale_cursor_file_does_not_reuse_history_cursor(self, store):
|
|
"""A stale .cursor file must not allocate a duplicate cursor."""
|
|
store.history_file.write_text(
|
|
'{"cursor": 10, "timestamp": "2026-04-01 10:00", "content": "valid"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
store._cursor_file.write_text("2", encoding="utf-8")
|
|
|
|
cursor = store.append_history("after stale cursor file")
|
|
|
|
assert cursor == 11
|
|
entries = store.read_unprocessed_history(since_cursor=0)
|
|
assert [e["cursor"] for e in entries] == [10, 11]
|
|
|
|
def test_cursor_file_stays_ahead_after_history_compaction(self, store):
|
|
"""A cursor counter ahead of the tail preserves monotonic allocation."""
|
|
store.history_file.write_text(
|
|
'{"cursor": 10, "timestamp": "2026-04-01 10:00", "content": "valid"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
store._cursor_file.write_text("100", encoding="utf-8")
|
|
|
|
cursor = store.append_history("after compacted history")
|
|
|
|
assert cursor == 101
|
|
|
|
def test_negative_cursor_file_content_falls_back(self, store):
|
|
"""A negative .cursor value is corrupt and should not produce negative IDs."""
|
|
store._cursor_file.write_text("-5", encoding="utf-8")
|
|
|
|
cursor = store.append_history("after negative cursor file")
|
|
|
|
assert cursor == 1
|
|
|
|
|
|
class TestReadUnprocessedWithCorruption:
|
|
"""``read_unprocessed_history`` must skip entries with invalid cursors
|
|
instead of crashing on comparison."""
|
|
|
|
def test_skips_string_cursor_entries(self, store):
|
|
"""Entries with string cursors are silently skipped."""
|
|
store.history_file.write_text(
|
|
'{"cursor": 1, "timestamp": "2026-04-01 10:00", "content": "valid1"}\n'
|
|
'{"cursor": "bad", "timestamp": "2026-04-01 10:01", "content": "corrupted"}\n'
|
|
'{"cursor": 3, "timestamp": "2026-04-01 10:02", "content": "valid3"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
entries = store.read_unprocessed_history(since_cursor=0)
|
|
assert len(entries) == 2
|
|
assert [e["cursor"] for e in entries] == [1, 3]
|
|
|
|
def test_mixed_corruption_preserves_order(self, store):
|
|
"""Valid entries maintain correct order despite corrupt neighbors."""
|
|
store.history_file.write_text(
|
|
'{"cursor": "x", "timestamp": "2026-04-01 10:00", "content": "bad"}\n'
|
|
'{"cursor": 2, "timestamp": "2026-04-01 10:01", "content": "good2"}\n'
|
|
'{"cursor": null, "timestamp": "2026-04-01 10:02", "content": "also bad"}\n'
|
|
'{"cursor": 4, "timestamp": "2026-04-01 10:03", "content": "good4"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
entries = store.read_unprocessed_history(since_cursor=0)
|
|
assert [e["cursor"] for e in entries] == [2, 4]
|
|
|
|
def test_all_valid_still_works(self, store):
|
|
"""Normal operation unaffected — baseline regression check."""
|
|
store.append_history("event 1")
|
|
store.append_history("event 2")
|
|
store.append_history("event 3")
|
|
entries = store.read_unprocessed_history(since_cursor=1)
|
|
assert len(entries) == 2
|
|
assert entries[0]["cursor"] == 2
|
|
assert entries[1]["cursor"] == 3
|
|
|
|
|
|
class TestCursorValidationInvariant:
|
|
"""First-principles checks: the cursor validity rules and the
|
|
observability we layer on top of them."""
|
|
|
|
def test_bool_cursor_rejected(self, store):
|
|
"""``isinstance(True, int) is True`` in Python; the guard must
|
|
still treat ``{"cursor": true}`` as corruption, otherwise a
|
|
boolean silently becomes cursor ``1`` / ``0`` downstream.
|
|
"""
|
|
assert MemoryStore._valid_cursor(True) is None
|
|
assert MemoryStore._valid_cursor(False) is None
|
|
assert MemoryStore._valid_cursor(-1) is None
|
|
assert MemoryStore._valid_cursor(5) == 5
|
|
assert MemoryStore._valid_cursor(0) == 0
|
|
|
|
store.history_file.write_text(
|
|
'{"cursor": 4, "timestamp": "2026-04-01 10:00", "content": "real"}\n'
|
|
'{"cursor": true, "timestamp": "2026-04-01 10:01", "content": "bool"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
store._cursor_file.unlink(missing_ok=True)
|
|
assert store.append_history("next") == 5
|
|
|
|
entries = store.read_unprocessed_history(since_cursor=0)
|
|
assert [e["cursor"] for e in entries] == [4, 5]
|
|
|
|
def test_negative_history_cursor_rejected(self, store):
|
|
"""A negative history cursor is corrupt and must not seed new writes."""
|
|
store.history_file.write_text(
|
|
'{"cursor": -5, "timestamp": "2026-04-01 10:00", "content": "negative"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
store._cursor_file.unlink(missing_ok=True)
|
|
|
|
assert store.append_history("next") == 1
|
|
entries = store.read_unprocessed_history(since_cursor=0)
|
|
assert [e["cursor"] for e in entries] == [1]
|
|
|
|
def test_next_cursor_returns_max_not_just_last_int(self, store):
|
|
"""Under adversarial corruption, file order ≠ numeric order. The
|
|
recovery scan must return ``max(valid cursors) + 1``, not the
|
|
first int seen from the tail, so the returned cursor is strictly
|
|
greater than every legitimate cursor already on disk.
|
|
"""
|
|
# Tail is corrupt → recovery scan runs. Valid cursors are 100
|
|
# and 5, in that order on disk; a naive "first int from the tail"
|
|
# recovery would return 6, which would then silently collide with
|
|
# the existing cursor 100. ``max`` is the only safe choice.
|
|
store.history_file.write_text(
|
|
'{"cursor": 100, "timestamp": "2026-04-01 10:00", "content": "high"}\n'
|
|
'{"cursor": 5, "timestamp": "2026-04-01 10:01", "content": "out of order"}\n'
|
|
'{"cursor": "poison", "timestamp": "2026-04-01 10:02", "content": "tail corrupt"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
store._cursor_file.unlink(missing_ok=True)
|
|
assert store.append_history("safe next") == 101
|
|
|
|
def test_corruption_is_logged_exactly_once_per_store(self, store, caplog):
|
|
"""Observability without spam: the first invalid cursor emits one
|
|
warning, subsequent reads on the same store stay quiet. Without
|
|
this, a poisoned file produces one warning per agent turn."""
|
|
import logging
|
|
|
|
from loguru import logger as loguru_logger
|
|
|
|
store.history_file.write_text(
|
|
'{"cursor": "bad1", "timestamp": "2026-04-01 10:00", "content": "x"}\n'
|
|
'{"cursor": 2, "timestamp": "2026-04-01 10:01", "content": "y"}\n',
|
|
encoding="utf-8",
|
|
)
|
|
store._cursor_file.unlink(missing_ok=True)
|
|
|
|
handler_id = loguru_logger.add(
|
|
caplog.handler, format="{message}", level="WARNING"
|
|
)
|
|
try:
|
|
with caplog.at_level(logging.WARNING):
|
|
store.read_unprocessed_history(since_cursor=0)
|
|
store.read_unprocessed_history(since_cursor=0)
|
|
store.append_history("another")
|
|
finally:
|
|
loguru_logger.remove(handler_id)
|
|
|
|
corruption_warnings = [
|
|
r for r in caplog.records if "invalid cursor" in r.getMessage()
|
|
]
|
|
assert len(corruption_warnings) == 1, (
|
|
"Expected exactly one corruption warning per store instance; "
|
|
f"got {len(corruption_warnings)}: {[r.getMessage() for r in corruption_warnings]}"
|
|
)
|