When updating a scope variable, update another with the same value Angular2

Good morning everyone.

I have a method that we say does something like this:

getAll(){
         this.commonServices.getAllList()
                           .subscribe(
                               res => {
                                    this.resultList= res;
                                    this.copieResultList= res;                               
                               },
                                err => {
                                    console.log("Error: " + err);
                                });

    }

So far so good. I call the service that will recover an array of objects and store its response in two scope variables. resultList and copieResultList . The problem is that below I have a method that does:

getOne(id: string){
        this.commonService.getOne(id)
                            .subscribe(
                                res => {
                                 console.log(this.resultList);
                                    this.resultList.length = 0;
                                    this.resultList= res;
                                 console.log(this.resultList);
                                },
                                err => {
                                    console.log("Prueba error: " + err);
                                });
    }

Here the problem begins. And is that the first console.log prints me the list as is logical. But the second one does not, the second one shows it to me empty. That is, having modified the resultList has also modified the copieResultList

  

The scope is not being modified by mistake in any other part of the code.

Any ideas?