Testing the functions of an instance contract with truffle

Question

I have contract A and contract B with the following structures:

contract A {
  int x;
  function setX(){
       x = _x;
     }
}

contract B {
   A[] contractInstances;
   
   function createContractInstance() {
       contractInstances.push(new A());
      }

}

How can I access the method setX() of the created instance, when I am doing the testing with truffle? P.S. when I try to access them directly from the array, it is not working, cause the js platform sees the contract as string addresses.

Answer 1

You have to inspect contract B to discover the instances.

By extension, you need something to inspect. Consider:

contract B {
   address[] public contractInstances;
   
   function createContractInstance() public returns(A newA) {
       A newA = new A();
       contractInstances.push(address(newA));
   }
}

Once you have that, then

const A = artifacts.require(A);
const B = artifacts.require(B); // separate .sol file

let aInstance = await b.contractInstances(0); // first one
let a = await A.at(aInstance);

Hope it helps.