BUG: clear only attribute errors in get_attr_string.h::maybe_get_attr (#14745)

* TST: check whether filtered warnings change behaviour in array()

Setting warnings from a converted object's `__getattr__` to errors
changes the behaviour of `numpy.array`. See #14735.

* MAINT: clear errors raised by `PyArray_LookupSpecial*`

1 files changed, 29 insertions, 0 deletions

diff --git a/numpy/core/tests/test_issue14735.py b/numpy/core/tests/test_issue14735.py
new file mode 100644
index 000000000..6105c8e6a
--- /dev/null
+++ b/numpy/core/tests/test_issue14735.py
@@ -0,0 +1,29 @@
+import pytest
+import warnings
+import numpy as np
+
+
+class Wrapper:
+    def __init__(self, array):
+        self.array = array
+
+    def __len__(self):
+        return len(self.array)
+
+    def __getitem__(self, item):
+        return type(self)(self.array[item])
+
+    def __getattr__(self, name):
+        if name.startswith("__array_"):
+            warnings.warn("object got converted", UserWarning, stacklevel=1)
+
+        return getattr(self.array, name)
+
+    def __repr__(self):
+        return "<Wrapper({self.array})>".format(self=self)
+
+@pytest.mark.filterwarnings("error")
+def test_getattr_warning():
+    array = Wrapper(np.arange(10))
+    with pytest.raises(UserWarning, match="object got converted"):
+        np.asarray(array)