Improves CheatBase error messages

Delta/Database/Cheats/CheatBase.swift

@@ -80,6 +80,8 @@ class CheatBase: GamesDatabase
     override init() throws
     {
         let fileURL = DatabaseManager.cheatBaseURL
+        guard FileManager.default.fileExists(atPath: fileURL.path) else { throw GamesDatabase.Error.doesNotExist }
+        
         self.connection = try Connection(fileURL.path)
         
         try super.init()

Delta/Database/Cheats/CheatBaseView.swift

@@ -8,6 +8,8 @@
 
 import SwiftUI
 
+import enum SQLite.Result
+
 @available(iOS 14, *)
 extension CheatBaseView
 {
@@ -212,8 +214,17 @@ struct CheatBaseView: View
                 Text("Unable to Load Cheats")
                     .font(.title)
                 
-                Text(error.localizedDescription)
+                if let error = error as? SQLite.Result
-                    .font(.callout)
+                {
+                    // SQLite.Result implements CustomStringConvertible.description, but not localizedDescription.
+                    Text(String(describing: error))
+                        .font(.callout)
+                }
+                else
+                {
+                    Text(error.localizedDescription)
+                        .font(.callout)
+                }
             }
             else if let filteredCheats = viewModel.filteredCheats, filteredCheats.isEmpty
             {

Delta/Database/OpenVGDB/GamesDatabase.swift

@@ -57,9 +57,17 @@ extension VirtualTable
 
 extension GamesDatabase
 {
-    enum Error: Swift.Error
+    enum Error: LocalizedError
     {
         case doesNotExist
+        
+        var errorDescription: String? {
+            switch self
+            {
+            case .doesNotExist:
+                return NSLocalizedString("The SQLite database could not be found.", comment: "")
+            }
+        }
     }
 }