Watching the video I heard the speaker say unit testing is rather easy, since state is always sitting next to code in your components. This is great and sounds

Watching the video I heard the speaker say unit testing is rather easy, since state is always sitting next to code in your components. This is great and sounds logical: test different input states and check against expected / consistent output. What I'm wondering, given the unidirectional flow and the design of flux as a whole: would Integration Testing be needed at all anymore? I mean, there's no state outside of the component that could possibly influence the component's consistency. Therefore, all needed testing could be done by simply unit-testing all components in isolation. That sounds pretty huge.