They literally cooperated with the occupation until Barbarossa because Stalin was angling to join the Axis.

Had the Soviet Axis talks gone as Stalin planned, the French Communists would have readily and eagerly lined up to collaborate on Stalin's orders, because they specifically didn't do shit to resist until Stalin ordered it.

This is also why I balk at dismissal of Social Democrats as being unworthy of being called leftist ever, that was a determination made by Stalin in the wake of Nordic socialist parties not bending the knee for him.

Stalin formed a new internationale specifically to exclude them and anyone who also didn't bend the knee, then meanwhile the same bastard orders non-cooperation with anti-fascist resistance because it'd harsh his street cred with the fascists.

Man sold out europe for the hope of negotiating control Bulgaria and Turkey out of letting everyone west of his borders eat it and die horribly.