Enable use outside of play mode (#12)

* Enables use outside of play mode

This can be useful when writing native dlls for the editor, e.g. custom model importer.
The unloading is currently done in OnDisable which may not be ideal.

* Add enableInEditMode, improved and tested execute in edit mode

Uses OnDestroy to unload
Tested in editor, builds compile

* Update scripts/Editor/DllManipulatorEditor.cs

Co-Authored-By: mcpiroman <38111589+mcpiroman@users.noreply.github.com>

* Review fixes

Co-authored-by: mcpiroman <38111589+mcpiroman@users.noreply.github.com>

Author: rogerbarton

scripts/DllManipulator.cs

@@ -653,6 +653,7 @@ public class DllManipulatorOptions
         public bool crashLogsStackTrace;
         public bool mockAllNativeFunctions;
         public bool onlyInEditor;
+        public bool enableInEditMode;
     }
 
     public enum DllLoadingMode

scripts/DllManipulatorScript.cs

@@ -1,12 +1,18 @@
-using System;
+using System;
 using System.Reflection;
 using System.Threading;
 using System.Linq;
 using UnityEngine;
 using UnityNativeTool.Internal;
+#if UNITY_EDITOR
+using UnityEditor;
+#endif
 
 namespace UnityNativeTool
 {
+    #if UNITY_EDITOR
+    [ExecuteInEditMode]
+    #endif
     public class DllManipulatorScript : MonoBehaviour
     {
         private static DllManipulatorScript _singletonInstance = null;
@@ -30,23 +36,45 @@ public class DllManipulatorScript : MonoBehaviour
             crashLogsStackTrace = false,
             mockAllNativeFunctions = true,
             onlyInEditor = true,
+            enableInEditMode = false
         };
 
         private void OnEnable()
         {
-#if !UNITY_EDITOR
-            if (Options.onlyInEditor)
+#if UNITY_EDITOR
+            if (_singletonInstance != null)
+            {
+                if (EditorApplication.isPlaying)
+                    Destroy(gameObject);
+                else
+                    enabled = false; //Don't destroy as the user may be editing a Prefab
+                return;
+            }
+            _singletonInstance = this;
+            
+            if(EditorApplication.isPlaying)
+                DontDestroyOnLoad(gameObject);
+
+            if(EditorApplication.isPlaying || Options.enableInEditMode)
+                Initialize();
+#else
+            if (Options.onlyInEditor) 
                 return;
-#endif
 
             if (_singletonInstance != null)
             {
                 Destroy(gameObject);
                 return;
             }
             _singletonInstance = this;
-            DontDestroyOnLoad(gameObject);
 
+            DontDestroyOnLoad(gameObject);
+            Initialize();
+#endif
+        }
+        
+        private void Initialize()
+        {
             var initTimer = System.Diagnostics.Stopwatch.StartNew();
 
             DllManipulator.Options = Options;
@@ -66,7 +94,8 @@ private void OnDestroy()
 
                 DllManipulator.UnloadAll();
                 DllManipulator.ForgetAllDlls();
-                DllManipulator.ClearCrashLogs();         
+                DllManipulator.ClearCrashLogs();
+                _singletonInstance = null;
             }
         }
     }

scripts/Editor/DllManipulatorEditor.cs

@@ -21,6 +21,10 @@ public class DllManipulatorEditor : Editor
             "If true, native functions will be mocked only in assembly that contains DllManipulator (usually Assembly-CSharp)");
         private static readonly GUIContent ONLY_IN_EDITOR = new GUIContent("Only in editor",
             "Whether to run only inside editor (which is recommended).");
+        private static readonly GUIContent ENABLE_IN_EDIT_MODE = new GUIContent("Enable in Edit Mode",
+            "Should the DLLs also be mocked in edit mode (i.e. even if you don't hit 'play' in editor). " +
+            "Turning this off when not needed improves performance when entering edit mode. " +
+            "Changes are currently only visible on the next time edit mode is entered (i.e. when OnEnable is called so hit 'play' then 'stop' to apply).");
         private static readonly GUIContent TARGET_ASSEMBLIES_GUI_CONTENT = new GUIContent("Target assemblies",
             "Choose from which assemblies to mock native functions");
         private static readonly GUIContent DLL_PATH_PATTERN_GUI_CONTENT = new GUIContent("DLL path pattern", 
@@ -246,6 +250,8 @@ private void DrawOptions(DllManipulatorOptions options)
             }
 
             options.onlyInEditor = EditorGUILayout.Toggle(ONLY_IN_EDITOR, options.onlyInEditor);
+            
+            options.enableInEditMode = EditorGUILayout.Toggle(ENABLE_IN_EDIT_MODE, options.enableInEditMode);
 
             options.dllPathPattern = EditorGUILayout.TextField(DLL_PATH_PATTERN_GUI_CONTENT, options.dllPathPattern);
 
@@ -334,4 +340,4 @@ public static void UnloadAll()
             DllManipulator.UnloadAll();
         }
     }
-}
+}