I keep getting invalid Resource Fatal error?

import Foundation

enum VendingSelection: String {
    case soda
    case dietSoda
    case chips
    case cookie
    case sandwich
    case wrap
    case candyBar
    case popTart
    case water
    case fruitJuice
    case sportsDrink
    case gum
}

protocol VendingItem {
    var price: Double { get }
    var quantity: Int { get set }
}

protocol VendingMachine {
    var selection: [VendingSelection] { get }
    var inventory: [VendingSelection: VendingItem] { get set }
    var amountDeposited: Double { get set }


    init(inventory: [VendingSelection: VendingItem])

    func vend(_ quantity: Int, _ selection: VendingSelection) throws

    func deposit(_ amount: Double)
}

struct Item: VendingItem {
    let price: Double
    var quantity: Int
}

enum InventoryError: Error {
    case invalidResource
    case conversionFailure
    case invalidSelection
}

class PlistConvertor {
    static func dictionary(fromFile name: String, ofType type: String) throws -> [String: AnyObject] {
        guard let path = Bundle.main.path(forResource: name, ofType: type) else {
            throw InventoryError.invalidResource
        }

        guard let dictionary = NSDictionary(contentsOfFile: path) as? [String: AnyObject] else {
            throw InventoryError.conversionFailure

        }

        return dictionary

    }
}

class InventoryUnarchiver {
    static func vendingInventory(fromDictionary dictionary: [String: AnyObject]) throws -> [VendingSelection: VendingItem] {
        var inventory: [VendingSelection: VendingItem] = [:]

        for (key, value) in dictionary {
            if let itemDictionary = value as? [String: Any], let price = itemDictionary["price"] as? Double,
                let quantity = itemDictionary["quantity"] as? Int {
                let item = Item(price: price, quantity: quantity)


                guard let selection = VendingSelection(rawValue: key) else {
                    throw InventoryError.invalidSelection
                }

                inventory.updateValue(item, forKey: selection) 

            }


        }


        return inventory
    }
}

class FoodVendingMachine: VendingMachine {
    let selection: [VendingSelection] = [.soda, .dietSoda, .chips, .cookie, .wrap, .sandwich, .candyBar, .popTart, .water, .fruitJuice, .sportsDrink, .gum]

    var inventory: [VendingSelection: VendingItem]

    var amountDeposited: Double = 10.0

    required init(inventory: [VendingSelection : VendingItem]) {
        self.inventory = inventory
    }

    func vend(_ quantity: Int, _ selection: VendingSelection) throws {}

    func deposit(_ amount: Double) {}

}