codekingpro/portable-devtools

1import subprocess
2import sys
3import textwrap
4
5import pytest
6
7from numpy.testing import IS_WASM
8
9
10@pytest.mark.skipif(IS_WASM, reason="can't start subprocess")
11def test_lazy_load():
12    # gh-22045. lazyload doesn't import submodule names into the namespace
13
14    # Test within a new process, to ensure that we do not mess with the
15    # global state during the test run (could lead to cryptic test failures).
16    # This is generally unsafe, especially, since we also reload the C-modules.
17    code = textwrap.dedent(r"""
18        import sys
19        from importlib.util import LazyLoader, find_spec, module_from_spec
20
21        # create lazy load of numpy as np
22        spec = find_spec("numpy")
23        module = module_from_spec(spec)
24        sys.modules["numpy"] = module
25        loader = LazyLoader(spec.loader)
26        loader.exec_module(module)
27        np = module
28
29        # test a subpackage import
30        from numpy.lib import recfunctions  # noqa: F401
31
32        # test triggering the import of the package
33        np.ndarray
34        """)
35    p = subprocess.run(
36        (sys.executable, '-c', code),
37        stdout=subprocess.PIPE,
38        stderr=subprocess.STDOUT,
39        encoding='utf-8',
40        check=False,
41    )
42    assert p.returncode == 0, p.stdout
43