From 10d63ac664ad725d45eee3c7b552f8ba05656bd6 Mon Sep 17 00:00:00 2001
From: LucasG0 <guillermou.lucas@gmail.com>
Date: Wed, 20 Mar 2024 00:52:38 +0100
Subject: [PATCH] Fix empy slicing an array backwards by relying on
 slice.indices

---
 python/pyarrow/array.pxi           | 38 +++---------------------------
 python/pyarrow/tests/test_array.py |  1 +
 2 files changed, 4 insertions(+), 35 deletions(-)

diff --git a/python/pyarrow/array.pxi b/python/pyarrow/array.pxi
index def4c5e9ba962..7feb902c05083 100644
--- a/python/pyarrow/array.pxi
+++ b/python/pyarrow/array.pxi
@@ -549,41 +549,9 @@ def _normalize_slice(object arrow_obj, slice key):
         Py_ssize_t start, stop, step
         Py_ssize_t n = len(arrow_obj)
 
-    step = key.step or 1
-
-    if key.start is None:
-        if step < 0:
-            start = n - 1
-        else:
-            start = 0
-    elif key.start < 0:
-        start = key.start + n
-        if start < 0:
-            start = 0
-    elif key.start >= n:
-        start = n
-    else:
-        start = key.start
-
-    if step < 0 and (key.stop is None or key.stop < -n):
-        stop = -1
-    elif key.stop is None:
-        stop = n
-    elif key.stop < 0:
-        stop = key.stop + n
-        if stop < 0:  # step > 0 in this case.
-            stop = 0
-    elif key.stop >= n:
-        stop = n
-    else:
-        stop = key.stop
-
-    if step != 1:
-        indices = np.arange(start, stop, step)
-        return arrow_obj.take(indices)
-    else:
-        length = max(stop - start, 0)
-        return arrow_obj.slice(start, length)
+    start, stop, step = key.indices(n)
+    indices = np.arange(start, stop, step)
+    return arrow_obj.take(indices)
 
 
 cdef Py_ssize_t _normalize_index(Py_ssize_t index,
diff --git a/python/pyarrow/tests/test_array.py b/python/pyarrow/tests/test_array.py
index a8cd20720e437..a6df74b0d9a3d 100644
--- a/python/pyarrow/tests/test_array.py
+++ b/python/pyarrow/tests/test_array.py
@@ -486,6 +486,7 @@ def test_array_slice_negative_step():
         slice(None, None, 2),
         slice(0, 10, 2),
         slice(15, -25, -1),  # GH-38768
+        slice(-22, -22, -1),  # GH-40642
     ]
 
     for case in cases: