Object.assign is different with .set() ?

[vaynevayne]

Checked the source code, .set did nothing else, but Object.assign doesn't work, why is that?
https://github.com/fabricjs/fabric.js/blob/master/src/CommonMethods.ts#L29

const rectRef = useRef()
useEffect(()=>{
rectRef.current = new React()
},[])

useEffect(()=>{
Object.assign(rectRef.current,{top:20}) //  Actually this is not work 
rectRef.current.set({top:20})
},[options])

[asturur]

Set does call specific side effects for specific properties.
Each class has its own side effects.