test_import_utils.py

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
import pytest

from vllm.utils.import_utils import PlaceholderModule


def _raises_module_not_found():
    return pytest.raises(ModuleNotFoundError, match="No module named")


def test_placeholder_module_error_handling():
    placeholder = PlaceholderModule("placeholder_1234")

    with _raises_module_not_found():
        int(placeholder)

    with _raises_module_not_found():
        placeholder()

    with _raises_module_not_found():
        _ = placeholder.some_attr

    with _raises_module_not_found():
        # Test conflict with internal __name attribute
        _ = placeholder.name

    # OK to print the placeholder or use it in a f-string
    _ = repr(placeholder)
    _ = str(placeholder)

    # No error yet; only error when it is used downstream
    placeholder_attr = placeholder.placeholder_attr("attr")

    with _raises_module_not_found():
        int(placeholder_attr)

    with _raises_module_not_found():
        placeholder_attr()

    with _raises_module_not_found():
        _ = placeholder_attr.some_attr

    with _raises_module_not_found():
        # Test conflict with internal __module attribute
        _ = placeholder_attr.module