A small Unity editor utility for removing, restoring, or adjusting the default naming scheme for duplicate game objects.

RenameDuplicatesMenuItems.cs

/**
* MIT License
*
* Copyright (c) 2019 Jakob Bjerkness
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
* 
**/

using UnityEngine;
using UnityEditor;

using System.Linq;
using System.Collections.Generic;

/// <summary>
/// A small Unity editor utility for removing, restoring, or adjusting the default naming scheme for duplicate game objects.
/// </summary>
///
public class RenameDuplicatesMenuItems
{
    /// <summary>
    /// Stores data about a game object name along with the number of game objects with that name.
    /// </summary>
    ///
    private class GameObjectName
    {
        public string name;
        public int count;

        public GameObjectName(string name, int count)
        {
            this.name = name;
            this.count = count;
        }
    }

    private static List<GameObjectName> gameObjectNameList;

    /// <summary>
    /// Appends a new duplication number (e.g. "GameObject (3)") for every game object in the scene based on position in the hierarchy.
    ///                                                    ^^^
    /// <para> Position in the hierarchy is from top to bottom without regard for parent/child relationships.
    /// In other words, the ordering is based on a flattened version of the hierarchy. Every copy of a game object
    /// will have a unique number appended. </para>
    /// </summary>
    ///
    [MenuItem("Tools/Recalculate Duplicate Numbering/Based On Hierarchy Position (Unique)")]
    private static void renameDuplicates_Hierarchy()
    {
        gameObjectNameList = new List<GameObjectName>();

        foreach (GameObject gObj in getSortedTopLevelGameObjects())
        {
            recursivelyNameDuplicates(gObj, false, false);
        }
    }

    /// <summary>
    /// Appends a new duplication number (e.g. "GameObject (3)") for every game object in the scene based on position among siblings.
    ///                                                    ^^^
    /// <para> Position among siblings is from top to bottom relative to their parent. Compared to the 
    /// "Based On Hierarchy Position" option this method may create several game objects with 
    /// the same duplication number in the scene. However, sibling game objects will always be 
    /// uniquely numbered. </para>
    /// </summary>
    ///
    [MenuItem("Tools/Recalculate Duplicate Numbering/Based On Sibling Position")]
    private static void renameDuplicates_Sibling()
    {
        gameObjectNameList = new List<GameObjectName>();

        foreach (GameObject gObj in getSortedTopLevelGameObjects())
        {
            recursivelyNameDuplicates(gObj, false, true);
        }
    }

    /// <summary>
    /// Removes the duplication numbering (e.g. "GameObject (3)") from every game object in the scene.
    ///                                                     ^^^
    /// </summary>
    ///
    [MenuItem("Tools/Remove Duplicate Numbering")]
    private static void removeDuplicateNumbering()
    {
        gameObjectNameList = new List<GameObjectName>();

        foreach (GameObject gObj in getSortedTopLevelGameObjects())
        {
            recursivelyNameDuplicates(gObj, true, false);
        }
    }

    /// <summary>
    /// Returns an enumerable list that contains all the top level game objects
    /// in the hierarchy in order of their position in the hierarchy.
    /// </summary>
    ///
    private static IEnumerable<GameObject> getSortedTopLevelGameObjects()
    {
        var topLevelGameObjects = GameObject.FindObjectsOfType<GameObject>().Where(gameObj => gameObj.transform.parent == null);
        return topLevelGameObjects.OrderBy(gameObj => gameObj.transform.GetSiblingIndex()).ToArray();
    }

    /// <summary>
    /// Renames duplicates according to parameter options.
    /// </summary>
    /// 
    private static void recursivelyNameDuplicates(GameObject parent, bool removeNumbering, bool useSiblingPosition)
    {
        if (parent.transform.childCount > 0)
        {
            // Add all the children of the parent to a list
            List<GameObject> children = new List<GameObject>();
            foreach (Transform child in parent.transform)
            {
                children.Add(child.gameObject);
            }

            // Sort the children list by order in the hierarchy
            var sortedChildren = children.OrderBy(gameObj => gameObj.transform.GetSiblingIndex()).ToArray();

            // Decide whether to maintain a global or sibling only game object name count
            List<GameObjectName> nameList;
            if (useSiblingPosition)
            {
                nameList = new List<GameObjectName>();
            }
            else
            {
                nameList = gameObjectNameList;
            }

            // Rename the children based on the sorted order
            foreach (GameObject gObj in sortedChildren)
            {
                // Cut the duplication number off if the game object name has one
                if (gObj.name.EndsWith(")"))
                {
                    int stringIndex = gObj.name.IndexOf("(");

                    // Remove extra spaces between name and iteration number
                    for (int i = stringIndex; i > 0; i--)
                    {
                        if (gObj.name.ElementAt(i) == ' ')
                        {
                            stringIndex = i;
                        }
                        else
                        {
                            if (gObj.name.ElementAt(i) == '(') continue;
                            else break;
                        }
                    }

                    gObj.name = gObj.name.Substring(0, stringIndex);
                }

                if (!removeNumbering)
                {
                    // Append the correct iteration number to the name
                    bool listContainsName = false;
                    foreach (GameObjectName gameObjectName in nameList)
                    {
                        if (gameObjectName.name == gObj.name)
                        {
                            gameObjectName.count += 1;
                            gObj.name += " (" + gameObjectName.count + ")";

                            listContainsName = true;
                        }
                    }
                    if (!listContainsName)
                    {
                        nameList.Add(new GameObjectName(gObj.name, 0));
                        //nameList.Add(new GameObjectName(gObj.name, 1));
                        //gObj.name += " (1)";
                    }
                }

                recursivelyNameDuplicates(gObj, removeNumbering, useSiblingPosition);
            }
        }
    }
}