Unity Find & Remove Missing Scripts Recursively

FindMissingScriptsRecursively.cs

public static class FindMissingScriptsRecursively
{
		[MenuItem("Tools/Remove Missing Scripts Recursively")]
		private static void FindAndRemoveMissingInSelected()
		{
			// EditorUtility.CollectDeepHierarchy does not include inactive children
			var deeperSelection = Selection.gameObjects.SelectMany(go => go.GetComponentsInChildren<Transform>(true))
				.Select(t => t.gameObject);
			var prefabs = new HashSet<Object>();
			int compCount = 0;
			int goCount = 0;
			foreach (var go in deeperSelection)
			{
				int count = GameObjectUtility.GetMonoBehavioursWithMissingScriptCount(go);
				if (count > 0)
				{
					if (PrefabUtility.IsPartOfAnyPrefab(go))
					{
						RecursivePrefabSource(go, prefabs, ref compCount, ref goCount);
						count = GameObjectUtility.GetMonoBehavioursWithMissingScriptCount(go);
						// if count == 0 the missing scripts has been removed from prefabs
						if (count == 0)
							continue;
						// if not the missing scripts must be prefab overrides on this instance
					}

					Undo.RegisterCompleteObjectUndo(go, "Remove missing scripts");
					GameObjectUtility.RemoveMonoBehavioursWithMissingScript(go);
					compCount += count;
					goCount++;
				}
			}

			Debug.Log($"Found and removed {compCount} missing scripts from {goCount} GameObjects");
		}

		// Prefabs can both be nested or variants, so best way to clean all is to go through them all
		// rather than jumping straight to the original prefab source.
		private static void RecursivePrefabSource(GameObject instance, HashSet<Object> prefabs, ref int compCount,
			ref int goCount)
		{
			var source = PrefabUtility.GetCorrespondingObjectFromSource(instance);
			// Only visit if source is valid, and hasn't been visited before
			if (source == null || !prefabs.Add(source))
				return;

			// go deep before removing, to differantiate local overrides from missing in source
			RecursivePrefabSource(source, prefabs, ref compCount, ref goCount);

			int count = GameObjectUtility.GetMonoBehavioursWithMissingScriptCount(source);
			if (count > 0)
			{
				Undo.RegisterCompleteObjectUndo(source, "Remove missing scripts");
				GameObjectUtility.RemoveMonoBehavioursWithMissingScript(source);
				compCount += count;
				goCount++;
			}
		}
	}