Actually, Hitler and Stalin got on rather well after the signing of the 1939 non-aggression pact. They agreed on the partitioning of conquered Poland, the Soviets shipped lots of ore & materiel to the Third Reich, etc.
Stalin was absolutely gobsmacked when the Nazis invaded the USSR, and felt a keen sense of betrayal. How could his colleague Adolf do such a thing?
Stalin was trying to avoid an provocations until 1943, when he felt the Red Army was ready to launch an attack on Germany, but Hitler beat him to the punch. Stalin wanted a war in the West to make it easy for the Red Army, but France's quick fall ruined those plans.