Fixed issue in which Unity types could be referenced from multiple assemblies.

also added some more log and pointed out that 2018.1 is the recommend version to run the converter.

EditorIntegration/Assets/UnityScript2CSharp/Editor/UnityScript2CSharpRunner.cs

@@ -2,16 +2,21 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
-using System.Linq;
 using System.Threading;
 using Assets.Editor;
 using UnityEditor;
-using UnityEditor.Compilation;
 using UnityEngine;
-using UnityEngine.SceneManagement;
 using Application = UnityEngine.Application;
 using Debug = UnityEngine.Debug;
 
+#if UNITY_2017_3_OR_NEWER        
+
+using System.Linq;
+using UnityEngine.SceneManagement;
+using UnityEditor.Compilation;
+
+#endif
+
 [Serializable]
 public class UnityScript2CSharpRunner : UnityEditor.EditorWindow
 {
@@ -248,7 +253,8 @@ public class UnityScript2CSharpRunner : UnityEditor.EditorWindow
 
             var referencedAssemblies = CompilationPipeline.GetAssemblies()
                                             .SelectMany(a => a.compiledAssemblyReferences)
-                                            .Where(a => !a.Contains(unityInstallPath) || a.Contains("UnityExtensions"));
+                                            .Where(a => !a.Contains(unityInstallPath) || a.Contains("UnityExtensions"))
+                                            .Distinct(StringComparer.InvariantCultureIgnoreCase);
             
             foreach (var assemblyPath in referencedAssemblies)
             {

UnityScript2CSharp/Program.cs

@@ -234,16 +234,8 @@ namespace UnityScript2CSharp
         private static void AppendUnityAssembliesReferences(string unityAssembliesRootPath, List<string> references)
         {
             var modularizedUnityEngineFolder = Path.Combine(unityAssembliesRootPath, "UnityEngine");
-            if (Directory.Exists(modularizedUnityEngineFolder))
-            {
-                foreach (var assemblyPath in Directory.GetFiles(modularizedUnityEngineFolder, "*.dll"))
-                {
-                    references.Add(assemblyPath);
-                }
-            }
-            else
-                references.Add(Path.Combine(unityAssembliesRootPath, "UnityEngine.dll"));
             
+            references.Add(Path.Combine(unityAssembliesRootPath, "UnityEngine.dll"));
             references.Add(Path.Combine(unityAssembliesRootPath, "UnityEditor.dll"));
         }
 
@@ -331,6 +323,13 @@ namespace UnityScript2CSharp
 
             Console.WriteLine("Converting '{0}' ({1} scripts)", assemblyType, scripts.Count);
 
+            if (args.Verbose)
+            {
+                Console.WriteLine("Referenced assemblies:");
+                foreach(var r in references)
+                    System.Console.WriteLine($"\t{r}");
+            }
+
             Action<string, string, int> handler = (scriptPath, context, unsupportedCount) => HandleConvertedScript(scriptPath, context, args.RemoveOriginalFiles, args.Verbose, unsupportedCount);
             if (args.DryRun)
                 handler = (_, __, ___) => {};

readme.md

@@ -17,7 +17,7 @@ Before running the conversion tool:
 
 1. Keep in mind that you'll have best results (i.e, a smoother conversion process) if your UnityScripts have  *#pragma strict* applied to them.
 
-1. Launch Unity editor (**preferably, 2018.2**) and make sure you allow APIUpdater to run and update any obsolete API usages. This is necessary to avoid compilation errors during the conversion.
+1. Launch Unity editor (**preferably, 2018.1**) and make sure you allow APIUpdater to run and update any obsolete API usages. This is necessary to avoid compilation errors during the conversion.
 
 Next step is to run the converter. For that we recomend trying the _Editor Unity Package Integration_ first: