From 29158b6dbbf0b78679ddb3e33a42f76b8ca4bcb2 Mon Sep 17 00:00:00 2001
From: Yannick Jadoul <yannick.jadoul@belgacom.net>
Date: Thu, 31 Oct 2019 18:42:23 +0100
Subject: [PATCH] Fixing SystemError when nb_bool/nb_nonzero sets a Python
 exception in type_caster<bool>::load

---
 include/pybind11/cast.h       | 3 +++
 tests/test_builtin_casters.py | 4 ++++
 2 files changed, 7 insertions(+)

diff --git a/include/pybind11/cast.h b/include/pybind11/cast.h
index 90407eb984..50f6b607cf 100644
--- a/include/pybind11/cast.h
+++ b/include/pybind11/cast.h
@@ -1173,6 +1173,9 @@ template <> class type_caster<bool> {
                 value = (bool) res;
                 return true;
             }
+            else {
+                PyErr_Clear();
+            }
         }
         return false;
     }
diff --git a/tests/test_builtin_casters.py b/tests/test_builtin_casters.py
index 73cc465f5b..abbfcec493 100644
--- a/tests/test_builtin_casters.py
+++ b/tests/test_builtin_casters.py
@@ -318,11 +318,15 @@ def test_numpy_bool():
     import numpy as np
     convert, noconvert = m.bool_passthrough, m.bool_passthrough_noconvert
 
+    def cant_convert(v):
+        pytest.raises(TypeError, convert, v)
+
     # np.bool_ is not considered implicit
     assert convert(np.bool_(True)) is True
     assert convert(np.bool_(False)) is False
     assert noconvert(np.bool_(True)) is True
     assert noconvert(np.bool_(False)) is False
+    cant_convert(np.zeros(2, dtype='int'))
 
 
 def test_int_long():