minor fix and extension to type inference for builtin type operations

Cython/Compiler/ExprNodes.py

@@ -4766,10 +4766,12 @@ class BinopNode(ExprNode):
                         return type1
                     # multiplication of containers/numbers with an
                     # integer value always (?) returns the same type
-                    if type1.is_int:
-                        return type2
-                    elif type2.is_int:
+                    if type2.is_int:
                         return type1
+            elif type2.is_builtin_type and type1.is_int and self.operator == '*':
+                # multiplication of containers/numbers with an
+                # integer value always (?) returns the same type
+                return type2
             return py_object_type
         else:
             return self.compute_c_result_type(type1, type2)

tests/run/type_inference.pyx

@@ -104,10 +104,12 @@ def builtin_type_operations():
     >>> builtin_type_operations()
     """
     b1 = b'a' * 10
+    b1 = 10 * b'a'
     assert typeof(b1) == "bytes object", typeof(b1)
     b2 = b'a' + b'b'
     assert typeof(b2) == "bytes object", typeof(b2)
     u1 = u'a' * 10
+    u1 = 10 * u'a'
     assert typeof(u1) == "unicode object", typeof(u1)
     u2 = u'a' + u'b'
     assert typeof(u2) == "unicode object", typeof(u2)