Merge pull request #369 from isuruf/dummy

Fix a bug in converting C++ Dummy objects to Python

Author: isuruf

symengine/lib/symengine_wrapper.pyx

@@ -71,7 +71,7 @@ cdef object c2py(rcp_const_basic o):
             return S.ImaginaryUnit
         r = Complex.__new__(Complex)
     elif (symengine.is_a_Dummy(deref(o))):
-        r = Symbol.__new__(Dummy)
+        r = Dummy.__new__(Dummy)
     elif (symengine.is_a_Symbol(deref(o))):
         if (symengine.is_a_PySymbol(deref(o))):
             return <object>(deref(symengine.rcp_static_cast_PySymbol(o)).get_py_object())

symengine/tests/test_symbol.py

@@ -159,6 +159,7 @@ def test_dummy():
 
     assert x1 == x2
     assert x1 != xdummy1
+    assert xdummy1 == (xdummy1 + 1) - 1
     assert xdummy1 != xdummy2
     assert Dummy() != Dummy()
     assert Dummy('x') != Dummy('x')