From 59a4cb0d41af5eeec91b9d25cfcdb0ea2ac6391b Mon Sep 17 00:00:00 2001
From: Marcel Stimberg <marcel.stimberg@sorbonne-universite.fr>
Date: Mon, 5 Feb 2024 16:23:44 +0100
Subject: [PATCH] Use cpow=True in Python

Avoids that x**y becomes a float for two integers, leading to compilation errors
cpow=True has been the default in Cython, but it changed to cpow=False with Cython 3.0

Fixes #1500
---
 .../cython_rt/templates/common_group.pyx       |  1 +
 brian2/tests/test_functions.py                 | 18 ++++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/brian2/codegen/runtime/cython_rt/templates/common_group.pyx b/brian2/codegen/runtime/cython_rt/templates/common_group.pyx
index 881fc74f9..0b24c5a3c 100644
--- a/brian2/codegen/runtime/cython_rt/templates/common_group.pyx
+++ b/brian2/codegen/runtime/cython_rt/templates/common_group.pyx
@@ -3,6 +3,7 @@
 #cython: boundscheck=False
 #cython: wraparound=False
 #cython: cdivision=False
+#cython: cpow=True
 #cython: infer_types=True
 {% endmacro %}
 
diff --git a/brian2/tests/test_functions.py b/brian2/tests/test_functions.py
index 811b58d8c..5d1683943 100644
--- a/brian2/tests/test_functions.py
+++ b/brian2/tests/test_functions.py
@@ -187,6 +187,24 @@ def test_bool_to_int():
     assert_equal(s_mon.intexpr2.flatten(), [1, 0])
 
 
+@pytest.mark.standalone_compatible
+def test_integer_power():
+    # See github issue #1500
+    G = NeuronGroup(
+        3,
+        """
+        intval1 : integer
+        intval2 : integer
+        k : integer (constant)
+        """,
+    )
+    G.k = [0, 1, 2]
+    G.run_regularly("intval1 = 2**k; intval2 = (-1)**k")
+    run(defaultclock.dt)
+    assert_equal(G.intval1[:], [1, 2, 4])
+    assert_equal(G.intval2[:], [1, -1, 1])
+
+
 @pytest.mark.codegen_independent
 def test_timestep_function():
     dt = defaultclock.dt_