2026-1-6

venv/Lib/site-packages/numpy/tests/test_reloading.py

@@ -0,0 +1,76 @@
+import pickle
+import subprocess
+import sys
+import textwrap
+from importlib import reload
+
+import pytest
+
+import numpy.exceptions as ex
+from numpy.testing import IS_WASM, assert_, assert_equal, assert_raises
+
+
+@pytest.mark.thread_unsafe(reason="reloads global module")
+def test_numpy_reloading():
+    # gh-7844. Also check that relevant globals retain their identity.
+    import numpy as np
+    import numpy._globals
+
+    _NoValue = np._NoValue
+    VisibleDeprecationWarning = ex.VisibleDeprecationWarning
+    ModuleDeprecationWarning = ex.ModuleDeprecationWarning
+
+    with pytest.warns(UserWarning):
+        reload(np)
+    assert_(_NoValue is np._NoValue)
+    assert_(ModuleDeprecationWarning is ex.ModuleDeprecationWarning)
+    assert_(VisibleDeprecationWarning is ex.VisibleDeprecationWarning)
+
+    assert_raises(RuntimeError, reload, numpy._globals)
+    with pytest.warns(UserWarning):
+        reload(np)
+    assert_(_NoValue is np._NoValue)
+    assert_(ModuleDeprecationWarning is ex.ModuleDeprecationWarning)
+    assert_(VisibleDeprecationWarning is ex.VisibleDeprecationWarning)
+
+def test_novalue():
+    import numpy as np
+    for proto in range(2, pickle.HIGHEST_PROTOCOL + 1):
+        assert_equal(repr(np._NoValue), '<no value>')
+        assert_(pickle.loads(pickle.dumps(np._NoValue,
+                                          protocol=proto)) is np._NoValue)
+
+
+@pytest.mark.skipif(IS_WASM, reason="can't start subprocess")
+def test_full_reimport():
+    # Reimporting numpy like this is not safe due to use of global C state,
+    # and has unexpected side effects. Test that an ImportError is raised.
+    # When all extension modules are isolated, this should test that clearing
+    # sys.modules and reimporting numpy works without error.
+
+    # Test within a new process, to ensure that we do not mess with the
+    # global state during the test run (could lead to cryptic test failures).
+    # This is generally unsafe, especially, since we also reload the C-modules.
+    code = textwrap.dedent(r"""
+        import sys
+        import numpy as np
+
+        for k in [k for k in sys.modules if k.startswith('numpy')]:
+            del sys.modules[k]
+
+        try:
+            import numpy as np
+        except ImportError as err:
+            if str(err) != "cannot load module more than once per process":
+                raise SystemExit(f"Unexpected ImportError: {err}")
+        else:
+            raise SystemExit("DID NOT RAISE ImportError")
+        """)
+    p = subprocess.run(
+        (sys.executable, '-c', code),
+        stdout=subprocess.PIPE,
+        stderr=subprocess.STDOUT,
+        encoding='utf-8',
+        check=False,
+    )
+    assert p.returncode == 0, p.stdout