Files
vllm/tests/utils_/test_async_utils.py
2025-10-19 05:20:55 -07:00

43 lines
1.3 KiB
Python

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
import asyncio
from collections.abc import AsyncIterator
import pytest
from vllm.utils.async_utils import merge_async_iterators
async def _mock_async_iterator(idx: int):
try:
while True:
yield f"item from iterator {idx}"
await asyncio.sleep(0.1)
except asyncio.CancelledError:
print(f"iterator {idx} cancelled")
@pytest.mark.asyncio
async def test_merge_async_iterators():
iterators = [_mock_async_iterator(i) for i in range(3)]
merged_iterator = merge_async_iterators(*iterators)
async def stream_output(generator: AsyncIterator[tuple[int, str]]):
async for idx, output in generator:
print(f"idx: {idx}, output: {output}")
task = asyncio.create_task(stream_output(merged_iterator))
await asyncio.sleep(0.5)
task.cancel()
with pytest.raises(asyncio.CancelledError):
await task
for iterator in iterators:
try:
await asyncio.wait_for(anext(iterator), 1)
except StopAsyncIteration:
# All iterators should be cancelled and print this message.
print("Iterator was cancelled normally")
except (Exception, asyncio.CancelledError) as e:
raise AssertionError() from e