BUG: Fix matrix PendingDeprecationWarning suppression for pytest 3.8+.

Pytest < 3.8 ignored warnings issued during test collection, but that
changed in pytest 3.8 and the method NumPy used to suppress the
PendingDeprecationWarning for matrices no longer worked, or rather, was
exposed as not working. The fix here is to suppress the warning in
pytest.ini and pytesttester.py , which should work as long as the tests
are the only places left where NumPy uses matrices.

An alternate fix is to delay the construction of matrices in the tests
until they are actually run, which has the virtue of test localization
but is a bit more complicated.

See pytest-dev/pytest#3945 for discussion.

Author: charris

numpy/_pytesttester.py

@@ -160,6 +160,24 @@ def __call__(self, label='fast', verbose=1, extra_argv=None,
             "-W ignore::UserWarning:cpuinfo",
             ]
 
+        # When testing matrices, ignore their PendingDeprecationWarnings
+        pytest_args += [
+            "-W ignore:the matrix subclass is not",
+            ]
+
+        # Ignore python2.7 -3 warnings
+        pytest_args += [
+            r"-W ignore:sys\.exc_clear\(\) not supported in 3\.x:DeprecationWarning",
+            r"-W ignore:in 3\.x, __setslice__:DeprecationWarning",
+            r"-W ignore:in 3\.x, __getslice__:DeprecationWarning",
+            r"-W ignore:buffer\(\) not supported in 3\.x:DeprecationWarning",
+            r"-W ignore:CObject type is not supported in 3\.x:DeprecationWarning",
+            r"-W ignore:comparing unequal types not supported in 3\.x:DeprecationWarning",
+            r"-W ignore:the commands module has been removed in Python 3\.0:DeprecationWarning",
+            r"-W ignore:The 'new' module has been removed in Python 3\.0:DeprecationWarning",
+            ]
+
+
         if doctests:
             raise ValueError("Doctests not supported")
 

numpy/matrixlib/tests/test_defmatrix.py

@@ -1,12 +1,6 @@
 from __future__ import division, absolute_import, print_function
 
-# As we are testing matrices, we ignore its PendingDeprecationWarnings
-try:
-    import pytest
-    pytestmark = pytest.mark.filterwarnings(
-        'ignore:the matrix subclass is not:PendingDeprecationWarning')
-except ImportError:
-    pass
+import pytest
 
 try:
     # Accessing collections abstract classes from collections

numpy/matrixlib/tests/test_interaction.py

@@ -4,13 +4,7 @@
 """
 from __future__ import division, absolute_import, print_function
 
-# As we are testing matrices, we ignore its PendingDeprecationWarnings
-try:
-    import pytest
-    pytestmark = pytest.mark.filterwarnings(
-        'ignore:the matrix subclass is not:PendingDeprecationWarning')
-except ImportError:
-    pass
+import pytest
 
 import textwrap
 import warnings

numpy/matrixlib/tests/test_masked_matrix.py

@@ -1,14 +1,7 @@
 from __future__ import division, absolute_import, print_function
 
-# As we are testing matrices, we ignore its PendingDeprecationWarnings
-try:
-    import pytest
-    pytestmark = pytest.mark.filterwarnings(
-        'ignore:the matrix subclass is not:PendingDeprecationWarning')
-except ImportError:
-    pass
-
 import pickle
+import pytest
 
 import numpy as np
 from numpy.ma.testutils import (assert_, assert_equal, assert_raises,

numpy/matrixlib/tests/test_matrix_linalg.py

@@ -1,13 +1,7 @@
 """ Test functions for linalg module using the matrix class."""
 from __future__ import division, absolute_import, print_function
 
-# As we are testing matrices, we ignore its PendingDeprecationWarnings
-try:
-    import pytest
-    pytestmark = pytest.mark.filterwarnings(
-        'ignore:the matrix subclass is not:PendingDeprecationWarning')
-except ImportError:
-    pass
+import pytest
 
 import numpy as np
 

numpy/matrixlib/tests/test_multiarray.py

@@ -1,12 +1,6 @@
 from __future__ import division, absolute_import, print_function
 
-# As we are testing matrices, we ignore its PendingDeprecationWarnings
-try:
-    import pytest
-    pytestmark = pytest.mark.filterwarnings(
-        'ignore:the matrix subclass is not:PendingDeprecationWarning')
-except ImportError:
-    pass
+import pytest
 
 import numpy as np
 from numpy.testing import assert_, assert_equal, assert_array_equal

numpy/matrixlib/tests/test_numeric.py

@@ -1,12 +1,6 @@
 from __future__ import division, absolute_import, print_function
 
-# As we are testing matrices, we ignore its PendingDeprecationWarnings
-try:
-    import pytest
-    pytestmark = pytest.mark.filterwarnings(
-        'ignore:the matrix subclass is not:PendingDeprecationWarning')
-except ImportError:
-    pass
+import pytest
 
 import numpy as np
 from numpy.testing import assert_equal

numpy/matrixlib/tests/test_regression.py

@@ -1,12 +1,6 @@
 from __future__ import division, absolute_import, print_function
 
-# As we are testing matrices, we ignore its PendingDeprecationWarnings
-try:
-    import pytest
-    pytestmark = pytest.mark.filterwarnings(
-        'ignore:the matrix subclass is not:PendingDeprecationWarning')
-except ImportError:
-    pass
+import pytest
 
 import numpy as np
 from numpy.testing import assert_, assert_equal, assert_raises

pytest.ini

@@ -9,6 +9,9 @@ filterwarnings =
     ignore:Not importing directory
     ignore:numpy.dtype size changed
     ignore:numpy.ufunc size changed
+    ignore::UserWarning:cpuinfo,
+# Matrix PendingDeprecationWarning.
+    ignore:the matrix subclass is not
 # Ignore python2.7 -3 warnings
     ignore:sys\.exc_clear\(\) not supported in 3\.x:DeprecationWarning
     ignore:in 3\.x, __setslice__:DeprecationWarning
@@ -17,5 +20,7 @@ filterwarnings =
     ignore:CObject type is not supported in 3\.x:DeprecationWarning
     ignore:comparing unequal types not supported in 3\.x:DeprecationWarning
     ignore:the commands module has been removed in Python 3\.0:DeprecationWarning
+    ignore:The 'new' module has been removed in Python 3\.0:DeprecationWarning
+
 env =
     PYTHONHASHSEED=0