Stalin thought they got along OK before WWII, and even after the invasion of Poland in Sept. 1939.FA Hayek made the point that even when they were fighting, fascists and socialists recognized that they had more in common with each other than either did with liberals (not “liberals” as we know them but actual liberals like you and me):
The relative ease with which a young communist could be converted into a Nazi or vice versa was well known, best of all to the propagandists of the two parties. The communists and Nazis clashed more frequently with each other than with other parties simply because they competed for the same type of mind and reserved for each other the hatred of the heretic. Their practice showed how closely they are related. To both, the real enemy, the man with whom they had nothing in common, was the liberal of the old type. While to the Nazi the communist and to the communist the Nazi, and to both the socialist, are potential recruits made of the right timber, they both know that there can be no com- promise between them and those who really believe in individual freedom. - The Road to Serfdom
The problem is with the comparison is, the NAZI party allowed capitalists to function as long as they supported the party, I.E. Krupp.
The Communists, on the other hand, believe in pure government control over every bit of the economy.
The Communists were hated in NAZI Germany, absolutely hated. It was in full swing before the invasion of Poland. Hitler viewed the Russian as sub human..as well as every slavic ethnic person.