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JavaScript

Posted by shu Chan
shu Chan
2,951 Points

Cannot read property 'push' of undefined

Hello, I'm having some trouble understanding why this is coming out to have a typeError: Cannot read property 'push' of undefined.

here is the code

function checkForShip(player, coordinates){
 let shipPresent, ship;
  for(var i=0; i < player.ships.length; i++){
    ship = player.ships[i]
    shipPresent = ship.locations.filter(function(actualCoordinate){
      return (actualCoordinate[0] === coordinates[0]) && (actualCoordinate[1] === coordinates[1])
    })[0]

    if(shipPresent){
      ship.damage.push(coordinates)
      return true;
    }
  }
      return false
}

here is the data that is coming from the test

describe('fireShip', function(){
  let fireOnShip = require('../game_logic/ship_methods').fireOnShip;

    it('should record damage on the given players ship at a given coordinate', function(){
       let player = {
         ships: [
           {
           locations: [[0,0], [0,1], [0,2]],
           damage: []      
           }
         ]
       }
       fireOnShip(player, [0,0])
       expect(player.ships[0].damage).to.not.be.empty
    })
  })

1 Answer

matthewnalliah
matthewnalliah
3,030 Points
matthewnalliah
matthewnalliah
3,030 Points

All I can see is that your data is commented out.

shu Chan
shu Chan
2,951 Points

sorry i've updated the question with the full process