MAINT: Use PySlice_GetIndicesEx instead of custom reimplementation

This has the side effects of:
- changing several IndexError exceptions into TypeErrors
- allowing slices like `arr[False:True]` as equivalent to
  `arr[0:1]` (because now we're using Python's logic for interpreting
  slices, and Python is happy with treating bools as integers in integer
  contexts).

It also deletes almost 100 lines of code :-).

While I was at it I also cleaned up some buggy uses of
PySlice_GetIndices (which is pretty broken -- e.g. the code was assuming
that it sets an exception on error, but this is not true! the Python
docs explicitly recommend that you never use it.)

1 files changed, 8 insertions, 0 deletions

diff --git a/numpy/core/include/numpy/npy_3kcompat.h b/numpy/core/include/numpy/npy_3kcompat.h
index db60a312c..cdab1bbe8 100644
--- a/numpy/core/include/numpy/npy_3kcompat.h
+++ b/numpy/core/include/numpy/npy_3kcompat.h
@@ -53,6 +53,14 @@ static NPY_INLINE int PyInt_Check(PyObject *op) {
  */
 #endif /* NPY_PY3K */
 
+/* Py3 changes PySlice_GetIndicesEx' first argument's type to PyObject* */
+#ifdef NPY_PY3K
+#  define NpySlice_GetIndicesEx PySlice_GetIndicesEx
+#else
+#  define NpySlice_GetIndicesEx(op, nop, start, end, step, slicelength) \
+    PySlice_GetIndicesEx((PySliceObject *)op, nop, start, end, step, slicelength)
+#endif
+
 /*
  * PyString -> PyBytes
  */