tests/single_controller/test_ray_utils_on_cpu.py

# Copyright 2025 Bytedance Ltd. and/or its affiliates
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
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#     http://www.apache.org/licenses/LICENSE-2.0
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import pytest
import ray

from verl.utils.ray_utils import parallel_put


# Initialize Ray for testing if not already done globally
@pytest.fixture()
def init_ray():
    ray.init(num_cpus=4)
    yield
    ray.shutdown()


def test_parallel_put_basic(init_ray):
    data = [1, "hello", {"a": 2}, [3, 4]]
    refs = parallel_put(data)
    assert len(refs) == len(data)
    retrieved_data = [ray.get(ref) for ref in refs]
    assert retrieved_data == data


def test_parallel_put_empty(init_ray):
    data = []
    with pytest.raises(AssertionError):
        _ = parallel_put(data)


def test_parallel_put_workers(init_ray):
    data = list(range(20))
    # Test with specific number of workers
    refs = parallel_put(data, max_workers=4)
    assert len(refs) == len(data)
    retrieved_data = [ray.get(ref) for ref in refs]
    assert retrieved_data == data
    # Test with default workers (should cap)
    refs_default = parallel_put(data)
    assert len(refs_default) == len(data)
    retrieved_data_default = [ray.get(ref) for ref in refs_default]
    assert retrieved_data_default == data