app.directive('photo', ['$http', 'modal', function($http, modal) {
    return {
        replace: true,
        templateUrl: '/assets/photo.html',
        transclude: false,
        scope: {
            result: '=',
            index: '@'
        },
        controller: ['$scope', '$http', 'modal', function($scope, $http, modal) {
            $scope.prev = $scope.index - 1;
            $scope.open = function() {
                debugger;
            };
        }]
    }
}]);

<div ng-repeat="r in results" photo result="r" index="$index"></div>

controller: function($scope) {
        $scope.prev = $scope.index - 1;
        $scope.open = function() {
            debugger;
        };
    }

$scope.open = function() {
  console.log($scope);
  debugger; //now you should see $scope.
};

app.directive('photo', ['$http', 'modal', function($http, modal) {
return {
    replace: true,
    templateUrl: '/assets/photo.html',
    transclude: false,
    scope: {
        result: '=',
        index: '@'
    },
    controller: function($scope, $http, modal) {
        $scope.prev = $scope.index - 1;
        $scope.open = function() {
            debugger;
        };
    }
}
}]);

var app = angular.module("moduleTest",[]);
app.directive("testDirective",function(){
    return {
        restrict: "A",
        scope: true,
        link: function(scope, element){
           //code
        }
    }
 });