[arrow] branch master updated: ARROW-2871: [Python] Raise when calling to_numpy() on boolean array

[uwe]

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The following commit(s) were added to refs/heads/master by this push:
     new 8443759  ARROW-2871: [Python] Raise when calling to_numpy() on boolean 
array
8443759 is described below

commit 8443759d03e9e4c9c7fc7dc4bd547d9d9143013f
Author: Wes McKinney <wesm+...@apache.org>
AuthorDate: Wed Jul 18 15:27:50 2018 +0200

    ARROW-2871: [Python] Raise when calling to_numpy() on boolean array
    
    Also marks that `to_numpy` API is experimental, since we need to figure out 
what to do about nulls (ARROW-2870)
    
    Author: Wes McKinney <wesm+...@apache.org>
    
    Closes #2277 from wesm/ARROW-2871 and squashes the following commits:
    
    c07b9b48 <Wes McKinney> Boolean is not supported in Array.to_numpy
---
 python/pyarrow/array.pxi           | 11 +++++++++--
 python/pyarrow/tests/test_array.py | 13 +++++++++++++
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/python/pyarrow/array.pxi b/python/pyarrow/array.pxi
index c2eb870..f209eb7 100644
--- a/python/pyarrow/array.pxi
+++ b/python/pyarrow/array.pxi
@@ -606,12 +606,19 @@ cdef class Array:
 
     def to_numpy(self):
         """
-        Construct a NumPy view of this array
+        EXPERIMENTAL: Construct a NumPy view of this array. Only supports
+        primitive arrays with the same memory layout as NumPy (i.e. integers,
+        floating point) without any nulls.
+
+        Returns
+        -------
+        arr : numpy.ndarray
+
         """
         if self.null_count:
             raise NotImplementedError('NumPy array view is only supported '
                                       'for arrays without nulls.')
-        if not is_primitive(self.type.id):
+        if not is_primitive(self.type.id) or self.type.id == _Type_BOOL:
             raise NotImplementedError('NumPy array view is only supported '
                                       'for primitive types.')
         buflist = self.buffers()
diff --git a/python/pyarrow/tests/test_array.py 
b/python/pyarrow/tests/test_array.py
index 29583e8..da3b247 100644
--- a/python/pyarrow/tests/test_array.py
+++ b/python/pyarrow/tests/test_array.py
@@ -108,6 +108,19 @@ def test_to_numpy_zero_copy():
     np.testing.assert_array_equal(np_arr, expected)
 
 
+def test_to_numpy_unsupported_types():
+    # ARROW-2871: Some primitive types are not yet supported in to_numpy
+    bool_arr = pa.array([True, False, True])
+
+    with pytest.raises(NotImplementedError):
+        bool_arr.to_numpy()
+
+    null_arr = pa.array([None, None, None])
+
+    with pytest.raises(NotImplementedError):
+        null_arr.to_numpy()
+
+
 def test_to_pandas_zero_copy():
     import gc