COMPAT: skip tests for numpy >= 1.12 with pow and integer inputs

closes pandas-dev#15363

CI: fix 3.5 build to numpy 1.11.3

Author: jreback

.gitignore

@@ -19,6 +19,7 @@
 .noseids
 .ipynb_checkpoints
 .tags
+.cache/
 
 # Compiled source #
 ###################

ci/requirements-3.5.build

@@ -1,4 +1,4 @@
 python-dateutil
 pytz
-numpy
+numpy=1.11.3
 cython

ci/requirements-3.5.run

@@ -1,6 +1,6 @@
 python-dateutil
 pytz
-numpy
+numpy=1.11.3
 openpyxl
 xlsxwriter
 xlrd

pandas/tests/test_expressions.py

@@ -12,7 +12,7 @@
 
 from pandas.core.api import DataFrame, Panel
 from pandas.computation import expressions as expr
-from pandas import compat
+from pandas import compat, _np_version_under1p12
 from pandas.util.testing import (assert_almost_equal, assert_series_equal,
                                  assert_frame_equal, assert_panel_equal,
                                  assert_panel4d_equal, slow)
@@ -78,6 +78,13 @@ def run_arithmetic_test(self, df, other, assert_func, check_dtype=False,
         if not compat.PY3:
             operations.append('div')
         for arith in operations:
+
+            # numpy >= 1.12 doesn't handle integers
+            # raised to integer powers
+            # https://github.com/pandas-dev/pandas/issues/15363
+            if arith == 'pow' and not _np_version_under1p12:
+                continue
+
             operator_name = arith
             if arith == 'div':
                 operator_name = 'truediv'
@@ -90,6 +97,7 @@ def run_arithmetic_test(self, df, other, assert_func, check_dtype=False,
             expr.set_use_numexpr(False)
             expected = op(df, other)
             expr.set_use_numexpr(True)
+
             result = op(df, other)
             try:
                 if check_dtype:
@@ -273,6 +281,13 @@ def testit():
 
                 for op, op_str in [('add', '+'), ('sub', '-'), ('mul', '*'),
                                    ('div', '/'), ('pow', '**')]:
+
+                    # numpy >= 1.12 doesn't handle integers
+                    # raised to integer powers
+                    # https://github.com/pandas-dev/pandas/issues/15363
+                    if op == 'pow' and not _np_version_under1p12:
+                        continue
+
                     if op == 'div':
                         op = getattr(operator, 'truediv', None)
                     else: