ENH: __array_function__ updates for NumPy 1.17.0

- Always enable __array_function__ overrides.
- Remove special cases for Python 2 compatibility.
- Document these changes in 1.17.0-notes.rst.

It will be good to see ASV numbers to understand the performance implications
of these changes. If need be, we can speed up NumPy functions internally by
using non-dispatched functions (with ``.__wrapped__``).

1 files changed, 0 insertions, 8 deletions

diff --git a/numpy/core/shape_base.py b/numpy/core/shape_base.py
index f8332c362..08e07bb66 100644
--- a/numpy/core/shape_base.py
+++ b/numpy/core/shape_base.py
@@ -217,11 +217,6 @@ def _arrays_for_stack_dispatcher(arrays, stacklevel=4):
     return arrays
 
 
-def _warn_for_nonsequence(arrays):
-    if not overrides.ENABLE_ARRAY_FUNCTION:
-        _arrays_for_stack_dispatcher(arrays, stacklevel=4)
-
-
 def _vhstack_dispatcher(tup):
     return _arrays_for_stack_dispatcher(tup)
 
@@ -279,7 +274,6 @@ def vstack(tup):
            [4]])
 
     """
-    _warn_for_nonsequence(tup)
     return _nx.concatenate([atleast_2d(_m) for _m in tup], 0)
 
 
@@ -331,7 +325,6 @@ def hstack(tup):
            [3, 4]])
 
     """
-    _warn_for_nonsequence(tup)
     arrs = [atleast_1d(_m) for _m in tup]
     # As a special case, dimension 0 of 1-dimensional arrays is "horizontal"
     if arrs and arrs[0].ndim == 1:
@@ -406,7 +399,6 @@ def stack(arrays, axis=0, out=None):
            [3, 4]])
 
     """
-    _warn_for_nonsequence(arrays)
     arrays = [asanyarray(arr) for arr in arrays]
     if not arrays:
         raise ValueError('need at least one array to stack')