Fix C++ assignments to references returned by operator[].

Closes #2671.

Cython/Compiler/ExprNodes.py

@@ -4102,7 +4102,7 @@ class IndexNode(_IndexingBaseNode):
                 # both exception handlers are the same.
                 translate_cpp_exception(code, self.pos,
                     "%s = %s;" % (self.result(), rhs.result()),
-                    self.result() if self.lhs.is_pyobject else None,
+                    self.result() if self.type.is_pyobject else None,
                     self.exception_value, self.in_nogil_context)
         else:
             code.putln(

tests/run/cpp_operators.pyx

@@ -9,48 +9,56 @@ from cython.operator cimport typeid, dereference as deref
 from libc.string cimport const_char
 from libcpp cimport bool
 
+
 cdef out(s, result_type=None):
     print '%s [%s]' % (s.decode('ascii'), result_type)
 
+
+cdef iout(int s, result_type=None):
+    print '%s [%s]' % (s, result_type)
+
+
 cdef extern from "cpp_operators_helper.h" nogil:
     cdef cppclass TestOps:
 
-        const_char* operator+()
-        const_char* operator-()
-        const_char* operator*()
-        const_char* operator~()
-        const_char* operator!()
+        const_char* operator+() except +
+        const_char* operator-() except +
+        const_char* operator*() except +
+        const_char* operator~() except +
+        const_char* operator!() except +
 
+        # FIXME: using 'except +' here leads to wrong calls ???
         const_char* operator++()
         const_char* operator--()
         const_char* operator++(int)
         const_char* operator--(int)
 
-        const_char* operator+(int)
-        const_char* operator+(int,const TestOps&)
-        const_char* operator-(int)
-        const_char* operator-(int,const TestOps&)
-        const_char* operator*(int)
+        const_char* operator+(int) except +
+        const_char* operator+(int,const TestOps&) except +
+        const_char* operator-(int) except +
+        const_char* operator-(int,const TestOps&) except +
+        const_char* operator*(int) except +
         # deliberately omitted operator* to test case where only defined outside class
-        const_char* operator/(int)
-        const_char* operator/(int,const TestOps&)
-        const_char* operator%(int)
-        const_char* operator%(int,const TestOps&)
-
-        const_char* operator|(int)
-        const_char* operator|(int,const TestOps&)
-        const_char* operator&(int)
-        const_char* operator&(int,const TestOps&)
-        const_char* operator^(int)
-        const_char* operator^(int,const TestOps&)
-        const_char* operator,(int)
-        const_char* operator,(int,const TestOps&)
-
-        const_char* operator<<(int)
-        const_char* operator<<(int,const TestOps&)
-        const_char* operator>>(int)
-        const_char* operator>>(int,const TestOps&)
-
+        const_char* operator/(int) except +
+        const_char* operator/(int,const TestOps&) except +
+        const_char* operator%(int) except +
+        const_char* operator%(int,const TestOps&) except +
+
+        const_char* operator|(int) except +
+        const_char* operator|(int,const TestOps&) except +
+        const_char* operator&(int) except +
+        const_char* operator&(int,const TestOps&) except +
+        const_char* operator^(int) except +
+        const_char* operator^(int,const TestOps&) except +
+        const_char* operator,(int) except +
+        const_char* operator,(int,const TestOps&) except +
+
+        const_char* operator<<(int) except +
+        const_char* operator<<(int,const TestOps&) except +
+        const_char* operator>>(int) except +
+        const_char* operator>>(int,const TestOps&) except +
+
+        # FIXME: using 'except +' here leads to invalid C++ code ???
         const_char* operator==(int)
         const_char* operator!=(int)
         const_char* operator>=(int)
@@ -58,25 +66,73 @@ cdef extern from "cpp_operators_helper.h" nogil:
         const_char* operator>(int)
         const_char* operator<(int)
 
-        const_char* operator[](int)
-        const_char* operator()(int)
-    
+        const_char* operator[](int) except +
+        const_char* operator()(int) except +
+
     # Defining the operator outside the class does work
     # but doesn't help when importing from pxd files
     # (they don't get imported)
-    const_char* operator+(float,const TestOps&)
+    const_char* operator+(float,const TestOps&) except +
     # deliberately omitted operator- to test case where only defined in class
-    const_char* operator*(float,const TestOps&)
-    const_char* operator/(float,const TestOps&)
-    const_char* operator%(float,const TestOps&)
-
-    const_char* operator|(float,const TestOps&)
-    const_char* operator&(float,const TestOps&)
-    const_char* operator^(float,const TestOps&)
-    const_char* operator,(float,const TestOps&)
-
-    const_char* operator<<(float,const TestOps&)
-    const_char* operator>>(float,const TestOps&)
+    const_char* operator*(float,const TestOps&) except +
+    const_char* operator/(float,const TestOps&) except +
+    const_char* operator%(float,const TestOps&) except +
+
+    const_char* operator|(float,const TestOps&) except +
+    const_char* operator&(float,const TestOps&) except +
+    const_char* operator^(float,const TestOps&) except +
+    const_char* operator,(float,const TestOps&) except +
+
+    const_char* operator<<(float,const TestOps&) except +
+    const_char* operator>>(float,const TestOps&) except +
+
+    cdef cppclass RefTestOps:
+
+        int& operator+() except +
+        int& operator-() except +
+        int& operator*() except +
+        int& operator~() except +
+        int& operator!() except +
+
+        int& operator++() except +
+        int& operator--() except +
+        int& operator++(int) except +
+        int& operator--(int) except +
+
+        int& operator+(int) except +
+        int& operator+(int,const TestOps&) except +
+        int& operator-(int) except +
+        int& operator-(int,const TestOps&) except +
+        int& operator*(int) except +
+        # deliberately omitted operator* to test case where only defined outside class
+        int& operator/(int) except +
+        int& operator/(int,const TestOps&) except +
+        int& operator%(int) except +
+        int& operator%(int,const TestOps&) except +
+
+        int& operator|(int) except +
+        int& operator|(int,const TestOps&) except +
+        int& operator&(int) except +
+        int& operator&(int,const TestOps&) except +
+        int& operator^(int) except +
+        int& operator^(int,const TestOps&) except +
+        int& operator,(int) except +
+        int& operator,(int,const TestOps&) except +
+
+        int& operator<<(int) except +
+        int& operator<<(int,const TestOps&) except +
+        int& operator>>(int) except +
+        int& operator>>(int,const TestOps&) except +
+
+        int& operator==(int) except +
+        int& operator!=(int) except +
+        int& operator>=(int) except +
+        int& operator<=(int) except +
+        int& operator>(int) except +
+        int& operator<(int) except +
+
+        int& operator[](int) except +
+        int& operator()(int) except +
 
     cdef cppclass TruthClass:
         TruthClass()
@@ -84,9 +140,11 @@ cdef extern from "cpp_operators_helper.h" nogil:
         bool operator bool()
         bool value
 
+
 cdef cppclass TruthSubClass(TruthClass):
     pass
 
+
 def test_unops():
     """
     >>> test_unops()
@@ -233,6 +291,7 @@ def test_cmp():
     out(t[0] < 1, typeof(t[0] < 1))
     del t
 
+
 def test_index_call():
     """
     >>> test_index_call()
@@ -244,6 +303,20 @@ def test_index_call():
     out(t[0](100), typeof(t[0](100)))
     del t
 
+
+def test_index_assignment():
+    """
+    >>> test_index_assignment()
+    0 [int &]
+    123 [int [&]]
+    """
+    cdef RefTestOps* t = new RefTestOps()
+    iout(t[0][100], typeof(t[0][100]))
+    t[0][99] = 123
+    iout(t[0](100), typeof(t[0](100)))
+    del t
+
+
 def test_bool_op():
     """
     >>> test_bool_op()

tests/run/cpp_operators_helper.h

@@ -76,6 +76,58 @@ NONMEMBER_BIN_OP2(&)
 NONMEMBER_BIN_OP2(^)
 NONMEMBER_BIN_OP2(COMMA)
 
+
+/* RefTestOps */
+
+#define REF_UN_OP(op) int& operator op () { return value; }
+#define REF_POST_UN_OP(op) int& operator op (int x) { x++; return value; }
+#define REF_BIN_OP(op) int& operator op (int x) { x++; return value; }
+
+class RefTestOps {
+    int value = 0;
+
+public:
+
+    REF_UN_OP(-);
+    REF_UN_OP(+);
+    REF_UN_OP(*);
+    REF_UN_OP(~);
+    REF_UN_OP(!);
+    REF_UN_OP(&);
+
+    REF_UN_OP(++);
+    REF_UN_OP(--);
+    REF_POST_UN_OP(++);
+    REF_POST_UN_OP(--);
+
+    REF_BIN_OP(+);
+    REF_BIN_OP(-);
+    REF_BIN_OP(*);
+    REF_BIN_OP(/);
+    REF_BIN_OP(%);
+
+    REF_BIN_OP(<<);
+    REF_BIN_OP(>>);
+
+    REF_BIN_OP(|);
+    REF_BIN_OP(&);
+    REF_BIN_OP(^);
+    REF_BIN_OP(COMMA);
+
+    REF_BIN_OP(==);
+    REF_BIN_OP(!=);
+    REF_BIN_OP(<=);
+    REF_BIN_OP(<);
+    REF_BIN_OP(>=);
+    REF_BIN_OP(>);
+
+    REF_BIN_OP([]);
+    REF_BIN_OP(());
+};
+
+
+/* TruthClass */
+
 class TruthClass {
 public:
   TruthClass() : value(false) {}