Add validatorList method

contracts/IBridgeValidators.sol

@@ -5,6 +5,6 @@ interface IBridgeValidators {
     function isValidator(address _validator) public view returns(bool);
     function requiredSignatures() public view returns(uint256);
     function owner() public view returns(address);
-    function getNextValidator(address _validator) public view returns(address);
     function getValidatorRewardAddress(address _validator) public view returns(address);
+    function validatorList() public view returns (address[]);
 }

contracts/upgradeable_contracts/BridgeValidators.sol

@@ -142,6 +142,20 @@ contract BridgeValidators is IBridgeValidators, EternalStorage, Ownable {
         return addressStorage[keccak256(abi.encodePacked("validatorsList", _address))];
     }
 
+    function validatorList() public view returns (address[]) {
+        address [] memory list = new address[](validatorCount());
+        uint256 counter = 0;
+        address nextValidator = getNextValidator(F_ADDR);
+
+        while (nextValidator != F_ADDR) {
+            list[counter] = nextValidator;
+            nextValidator = getNextValidator(nextValidator);
+            counter++;
+        }
+
+        return list;
+    }
+
     function setValidatorRewardAddress(address _validator, address _reward) internal {
         addressStorage[keccak256(abi.encodePacked("validatorsRewards", _validator))] = _reward;
     }

test/validators_test.js

@@ -228,4 +228,18 @@ contract('BridgeValidators', async (accounts) => {
       }
     })
   })
+  describe('#Validators list', () => {
+    it('should return validators list', async () => {
+      // Given
+      const validators = accounts.slice(0, 5)
+      const { initialize, validatorList } = bridgeValidators
+      await initialize(1, validators, accounts.slice(5), owner, { from: owner }).should.be.fulfilled
+
+      // When
+      const returnedList = await validatorList()
+
+      // Then
+      returnedList.should.be.eql(validators)
+    })
+  })
 })