TST: add broadcast_arrays() kwarg unit test for TypeError

tylerjereddy · tylerjereddy · commit 81bd37e73b85 · 2018-08-01T17:27:32.000-07:00
* broadcast_arrays() is now tested for the case when an invalid
keyword argument is used; the appropriate error string content
is also tested for

* the TypeError message produced in the above case has been restored
to the correct value in Python 3
diff --git a/numpy/lib/stride_tricks.py b/numpy/lib/stride_tricks.py
@@ -242,7 +242,7 @@ def broadcast_arrays(*args, **kwargs):
     subok = kwargs.pop('subok', False)
     if kwargs:
         raise TypeError('broadcast_arrays() got an unexpected keyword '
-                        'argument {!r}'.format(kwargs.keys()[0]))
+                        'argument {!r}'.format(list(kwargs.keys())[0]))
     args = [np.array(_m, copy=False, subok=subok) for _m in args]
 
     shape = _broadcast_shape(*args)
diff --git a/numpy/lib/tests/test_stride_tricks.py b/numpy/lib/tests/test_stride_tricks.py
@@ -3,7 +3,8 @@
 import numpy as np
 from numpy.core._rational_tests import rational
 from numpy.testing import (
-    assert_equal, assert_array_equal, assert_raises, assert_
+    assert_equal, assert_array_equal, assert_raises, assert_,
+    assert_raises_regex
     )
 from numpy.lib.stride_tricks import (
     as_strided, broadcast_arrays, _broadcast_shape, broadcast_to
@@ -57,6 +58,17 @@ def test_same():
     assert_array_equal(x, bx)
     assert_array_equal(y, by)
 
+def test_broadcast_kwargs():
+    # ensure that a TypeError is appropriately raised when
+    # np.broadcast_arrays() is called with any keyword
+    # argument other than 'subok'
+    x = np.arange(10)
+    y = np.arange(10)
+
+    with assert_raises_regex(TypeError,
+                             'broadcast_arrays\\(\\) got an unexpected keyword*'):
+        broadcast_arrays(x, y, dtype='float64')
+
 
 def test_one_off():
     x = np.array([[1, 2, 3]])
