Tests for conditional expressions with refernces.

tests/run/if_else_expr_cpp.pyx

+# mode: run
+# tag: condexpr, cpp
+
+cdef extern from "if_else_expr_cpp_helper.h":
+    cdef cppclass Holder:
+        int value
+        Holder()
+        Holder(int value)
+
+    cdef Holder v1
+    cdef Holder v2
+    cdef Holder& get_v1()
+    cdef Holder& get_v2()
+
+cdef reset() :
+    v1.value = 1
+    v2.value = 2
+
+def test_one_ref(bint b):
+    """
+    >>> test_one_ref(False)
+    1
+    >>> test_one_ref(True)
+    100
+    """
+    reset()
+    return (Holder(100) if b else get_v1()).value
+
+def test_both_ref(bint b):
+    """
+    >>> test_both_ref(False)
+    (1, 100)
+    >>> test_both_ref(True)
+    (100, 2)
+    """
+    reset()
+    try:
+        (get_v1() if b else get_v2()).value = 100
+        return v1.value, v2.value
+    finally:
+        reset()

tests/run/if_else_expr_cpp_helper.h

+class Holder {
+public:
+    int value;
+    Holder() : value(-1) { }
+    Holder(int value) : value(value) { }
+};
+
+Holder v1(1);
+Holder v2(2);
+
+Holder& get_v1() {
+    return v1;
+}
+
+Holder& get_v2() {
+    return v2;
+}