From 35998a0314d4660ccbf1341eb5c55d72236570de Mon Sep 17 00:00:00 2001
From: Jason Rhinelander <jason@imaginary.ca>
Date: Sat, 20 May 2017 20:34:51 -0400
Subject: [PATCH] Define both __div__ and __truediv__ for Python 2

Python 2 requires both `__div__` and `__truediv__` (and variants) for
compatibility with both regular Python 2 and Python 2 under `from
__future__ import division`.  Without both, division fails in one or the
other case.
---
 include/pybind11/operators.h | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/include/pybind11/operators.h b/include/pybind11/operators.h
index d054d9f97..562987b86 100644
--- a/include/pybind11/operators.h
+++ b/include/pybind11/operators.h
@@ -13,6 +13,9 @@
 
 #if defined(__clang__) && !defined(__INTEL_COMPILER)
 #  pragma clang diagnostic ignored "-Wunsequenced" // multiple unsequenced modifications to 'self' (when using def(py::self OP Type()))
+#elif defined(_MSC_VER)
+#  pragma warning(push)
+#  pragma warning(disable: 4127) // warning C4127: Conditional expression is constant
 #endif
 
 NAMESPACE_BEGIN(pybind11)
@@ -54,6 +57,11 @@ template <op_id id, op_type ot, typename L, typename R> struct op_ {
         using R_type = conditional_t<std::is_same<R, self_t>::value, Base, R>;
         using op = op_impl<id, ot, Base, L_type, R_type>;
         cl.def(op::name(), &op::execute, is_operator(), extra...);
+        #if PY_MAJOR_VERSION < 3
+        if (id == op_truediv || id == op_itruediv)
+            cl.def(id == op_itruediv ? "__idiv__" : ot == op_l ? "__div__" : "__rdiv__",
+                    &op::execute, is_operator(), extra...);
+        #endif
     }
     template <typename Class, typename... Extra> void execute_cast(Class &cl, const Extra&... extra) const {
         using Base = typename Class::type;
@@ -61,6 +69,11 @@ template <op_id id, op_type ot, typename L, typename R> struct op_ {
         using R_type = conditional_t<std::is_same<R, self_t>::value, Base, R>;
         using op = op_impl<id, ot, Base, L_type, R_type>;
         cl.def(op::name(), &op::execute_cast, is_operator(), extra...);
+        #if PY_MAJOR_VERSION < 3
+        if (id == op_truediv || id == op_itruediv)
+            cl.def(id == op_itruediv ? "__idiv__" : ot == op_l ? "__div__" : "__rdiv__",
+                    &op::execute, is_operator(), extra...);
+        #endif
     }
 };
 
@@ -108,11 +121,7 @@ inline op_<op_##id, op_u, self_t, undefined_t> op(const self_t &) {
 PYBIND11_BINARY_OPERATOR(sub,       rsub,         operator-,    l - r)
 PYBIND11_BINARY_OPERATOR(add,       radd,         operator+,    l + r)
 PYBIND11_BINARY_OPERATOR(mul,       rmul,         operator*,    l * r)
-#if PY_MAJOR_VERSION >= 3
 PYBIND11_BINARY_OPERATOR(truediv,   rtruediv,     operator/,    l / r)
-#else
-PYBIND11_BINARY_OPERATOR(div,       rdiv,         operator/,    l / r)
-#endif
 PYBIND11_BINARY_OPERATOR(mod,       rmod,         operator%,    l % r)
 PYBIND11_BINARY_OPERATOR(lshift,    rlshift,      operator<<,   l << r)
 PYBIND11_BINARY_OPERATOR(rshift,    rrshift,      operator>>,   l >> r)
@@ -129,11 +138,7 @@ PYBIND11_BINARY_OPERATOR(le,        ge,           operator<=,   l <= r)
 PYBIND11_INPLACE_OPERATOR(iadd,     operator+=,   l += r)
 PYBIND11_INPLACE_OPERATOR(isub,     operator-=,   l -= r)
 PYBIND11_INPLACE_OPERATOR(imul,     operator*=,   l *= r)
-#if PY_MAJOR_VERSION >= 3
 PYBIND11_INPLACE_OPERATOR(itruediv, operator/=,   l /= r)
-#else
-PYBIND11_INPLACE_OPERATOR(idiv,     operator/=,   l /= r)
-#endif
 PYBIND11_INPLACE_OPERATOR(imod,     operator%=,   l %= r)
 PYBIND11_INPLACE_OPERATOR(ilshift,  operator<<=,  l <<= r)
 PYBIND11_INPLACE_OPERATOR(irshift,  operator>>=,  l >>= r)
@@ -156,3 +161,7 @@ NAMESPACE_END(detail)
 using detail::self;
 
 NAMESPACE_END(pybind11)
+
+#if defined(_MSC_VER)
+#  pragma warning(pop)
+#endif