Files
crewAI/tests/flow_test.py
Devin AI b58bbb7d83 Add regression tests for issue #3828: Flow with unpickleable objects in state
- Add test_flow_with_rlock_in_state to verify Flow works with threading.RLock in state
- Add test_flow_with_nested_unpickleable_objects to verify Flow works with unpickleable objects nested in containers
- These tests ensure the issue from version 1.3.0 (TypeError: cannot pickle '_thread.RLock' object) doesn't get reintroduced
- The issue was resolved in the current main branch by removing the _copy_state() method that used copy.deepcopy()
- Tests verify that flows with memory components or other resources containing locks work correctly

Co-Authored-By: João <joao@crewai.com>
2025-11-04 10:23:00 +00:00

415 lines
12 KiB
Python

"""Test Flow creation and execution basic functionality."""
import asyncio
import threading
import pytest
from pydantic import BaseModel
from crewai.flow.flow import Flow, and_, listen, or_, router, start
def test_simple_sequential_flow():
"""Test a simple flow with two steps called sequentially."""
execution_order = []
class SimpleFlow(Flow):
@start()
def step_1(self):
execution_order.append("step_1")
@listen(step_1)
def step_2(self):
execution_order.append("step_2")
flow = SimpleFlow()
flow.kickoff()
assert execution_order == ["step_1", "step_2"]
def test_flow_with_multiple_starts():
"""Test a flow with multiple start methods."""
execution_order = []
class MultiStartFlow(Flow):
@start()
def step_a(self):
execution_order.append("step_a")
@start()
def step_b(self):
execution_order.append("step_b")
@listen(step_a)
def step_c(self):
execution_order.append("step_c")
@listen(step_b)
def step_d(self):
execution_order.append("step_d")
flow = MultiStartFlow()
flow.kickoff()
assert "step_a" in execution_order
assert "step_b" in execution_order
assert "step_c" in execution_order
assert "step_d" in execution_order
assert execution_order.index("step_c") > execution_order.index("step_a")
assert execution_order.index("step_d") > execution_order.index("step_b")
def test_cyclic_flow():
"""Test a cyclic flow that runs a finite number of iterations."""
execution_order = []
class CyclicFlow(Flow):
iteration = 0
max_iterations = 3
@start("loop")
def step_1(self):
if self.iteration >= self.max_iterations:
return # Do not proceed further
execution_order.append(f"step_1_{self.iteration}")
@listen(step_1)
def step_2(self):
execution_order.append(f"step_2_{self.iteration}")
@router(step_2)
def step_3(self):
execution_order.append(f"step_3_{self.iteration}")
self.iteration += 1
if self.iteration < self.max_iterations:
return "loop"
return "exit"
flow = CyclicFlow()
flow.kickoff()
expected_order = []
for i in range(flow.max_iterations):
expected_order.extend([f"step_1_{i}", f"step_2_{i}", f"step_3_{i}"])
assert execution_order == expected_order
def test_flow_with_and_condition():
"""Test a flow where a step waits for multiple other steps to complete."""
execution_order = []
class AndConditionFlow(Flow):
@start()
def step_1(self):
execution_order.append("step_1")
@start()
def step_2(self):
execution_order.append("step_2")
@listen(and_(step_1, step_2))
def step_3(self):
execution_order.append("step_3")
flow = AndConditionFlow()
flow.kickoff()
assert "step_1" in execution_order
assert "step_2" in execution_order
assert execution_order[-1] == "step_3"
assert execution_order.index("step_3") > execution_order.index("step_1")
assert execution_order.index("step_3") > execution_order.index("step_2")
def test_flow_with_or_condition():
"""Test a flow where a step is triggered when any of multiple steps complete."""
execution_order = []
class OrConditionFlow(Flow):
@start()
def step_a(self):
execution_order.append("step_a")
@start()
def step_b(self):
execution_order.append("step_b")
@listen(or_(step_a, step_b))
def step_c(self):
execution_order.append("step_c")
flow = OrConditionFlow()
flow.kickoff()
assert "step_a" in execution_order or "step_b" in execution_order
assert "step_c" in execution_order
assert execution_order.index("step_c") > min(
execution_order.index("step_a"), execution_order.index("step_b")
)
def test_flow_with_router():
"""Test a flow that uses a router method to determine the next step."""
execution_order = []
class RouterFlow(Flow):
@start()
def start_method(self):
execution_order.append("start_method")
@router(start_method)
def router(self):
execution_order.append("router")
# Ensure the condition is set to True to follow the "step_if_true" path
condition = True
return "step_if_true" if condition else "step_if_false"
@listen("step_if_true")
def truthy(self):
execution_order.append("step_if_true")
@listen("step_if_false")
def falsy(self):
execution_order.append("step_if_false")
flow = RouterFlow()
flow.kickoff()
assert execution_order == ["start_method", "router", "step_if_true"]
def test_async_flow():
"""Test an asynchronous flow."""
execution_order = []
class AsyncFlow(Flow):
@start()
async def step_1(self):
execution_order.append("step_1")
await asyncio.sleep(0.1)
@listen(step_1)
async def step_2(self):
execution_order.append("step_2")
await asyncio.sleep(0.1)
flow = AsyncFlow()
asyncio.run(flow.kickoff_async())
assert execution_order == ["step_1", "step_2"]
def test_flow_with_exceptions():
"""Test flow behavior when exceptions occur in steps."""
execution_order = []
class ExceptionFlow(Flow):
@start()
def step_1(self):
execution_order.append("step_1")
raise ValueError("An error occurred in step_1")
@listen(step_1)
def step_2(self):
execution_order.append("step_2")
flow = ExceptionFlow()
with pytest.raises(ValueError):
flow.kickoff()
# Ensure step_2 did not execute
assert execution_order == ["step_1"]
def test_flow_restart():
"""Test restarting a flow after it has completed."""
execution_order = []
class RestartableFlow(Flow):
@start()
def step_1(self):
execution_order.append("step_1")
@listen(step_1)
def step_2(self):
execution_order.append("step_2")
flow = RestartableFlow()
flow.kickoff()
flow.kickoff() # Restart the flow
assert execution_order == ["step_1", "step_2", "step_1", "step_2"]
def test_flow_with_custom_state():
"""Test a flow that maintains and modifies internal state."""
class StateFlow(Flow):
def __init__(self):
super().__init__()
self.counter = 0
@start()
def step_1(self):
self.counter += 1
@listen(step_1)
def step_2(self):
self.counter *= 2
assert self.counter == 2
flow = StateFlow()
flow.kickoff()
assert flow.counter == 2
def test_router_with_multiple_conditions():
"""Test a router that triggers when any of multiple steps complete (OR condition),
and another router that triggers only after all specified steps complete (AND condition).
"""
execution_order = []
class ComplexRouterFlow(Flow):
@start()
def step_a(self):
execution_order.append("step_a")
@start()
def step_b(self):
execution_order.append("step_b")
@router(or_("step_a", "step_b"))
def router_or(self):
execution_order.append("router_or")
return "next_step_or"
@listen("next_step_or")
def handle_next_step_or_event(self):
execution_order.append("handle_next_step_or_event")
@listen(handle_next_step_or_event)
def branch_2_step(self):
execution_order.append("branch_2_step")
@router(and_(handle_next_step_or_event, branch_2_step))
def router_and(self):
execution_order.append("router_and")
return "final_step"
@listen("final_step")
def log_final_step(self):
execution_order.append("log_final_step")
flow = ComplexRouterFlow()
flow.kickoff()
assert "step_a" in execution_order
assert "step_b" in execution_order
assert "router_or" in execution_order
assert "handle_next_step_or_event" in execution_order
assert "branch_2_step" in execution_order
assert "router_and" in execution_order
assert "log_final_step" in execution_order
# Check that the AND router triggered after both relevant steps:
assert execution_order.index("router_and") > execution_order.index(
"handle_next_step_or_event"
)
assert execution_order.index("router_and") > execution_order.index("branch_2_step")
# final_step should run after router_and
assert execution_order.index("log_final_step") > execution_order.index("router_and")
def test_flow_with_rlock_in_state():
"""Test that Flow can handle unpickleable objects like RLock in state.
Regression test for issue #3828: Flow should not crash when state contains
objects that cannot be deep copied (like threading.RLock).
In version 1.3.0, Flow._copy_state() used copy.deepcopy() which would fail
with "TypeError: cannot pickle '_thread.RLock' object" when state contained
threading locks (e.g., from memory components or LLM instances).
The current implementation no longer deep copies state, so this test verifies
that flows with unpickleable objects in state work correctly.
"""
execution_order = []
class StateWithRLock(BaseModel):
class Config:
arbitrary_types_allowed = True
counter: int = 0
lock: threading.RLock = None
class FlowWithRLock(Flow[StateWithRLock]):
@start()
def step_1(self):
execution_order.append("step_1")
self.state.counter += 1
@listen(step_1)
def step_2(self):
execution_order.append("step_2")
self.state.counter += 1
flow = FlowWithRLock()
flow._state.lock = threading.RLock()
flow.kickoff()
assert execution_order == ["step_1", "step_2"]
assert flow.state.counter == 2
def test_flow_with_nested_unpickleable_objects():
"""Test that Flow can handle unpickleable objects nested in containers.
Regression test for issue #3828: Verifies that unpickleable objects
nested inside dicts/lists in state don't cause crashes.
This simulates real-world scenarios where memory components or other
resources with locks might be stored in nested data structures.
"""
execution_order = []
class NestedState(BaseModel):
class Config:
arbitrary_types_allowed = True
data: dict = {}
items: list = []
class FlowWithNestedUnpickleable(Flow[NestedState]):
@start()
def step_1(self):
execution_order.append("step_1")
self.state.data["lock"] = threading.RLock()
self.state.data["value"] = 42
@listen(step_1)
def step_2(self):
execution_order.append("step_2")
self.state.items.append(threading.Lock())
self.state.items.append("normal_value")
@listen(step_2)
def step_3(self):
execution_order.append("step_3")
assert self.state.data["value"] == 42
assert len(self.state.items) == 2
flow = FlowWithNestedUnpickleable()
flow.kickoff()
assert execution_order == ["step_1", "step_2", "step_3"]
assert flow.state.data["value"] == 42
assert len(flow.state.items) == 2