Validator/Editor/Validators/SceneValidator.cs

using System.Collections.Generic;
using UnityEditor;
using UnityEngine;
using UnityEngine.SceneManagement;

namespace Validator.Editor
{
	public class SceneValidator : IValidator
	{
		public Report Validate()
		{
            Report report = new Report("SceneValidator");

            List<IValidatable> objects = FindAllObjectsOfType<IValidatable>();
			for (int i = 0; i < objects.Count; i++)
			{
                EditorUtility.DisplayProgressBar("SceneValidator", "Validate...", (float)i / objects.Count);

                objects[i].Validate(report);
            }
            EditorUtility.ClearProgressBar();

            return report;
		}

        private static List<GameObject> GetAllRootGameObjects()
        {
            List<GameObject> gameObjects = new List<GameObject>();

            for (int i = 0; i < SceneManager.sceneCount; i++)
            {
                EditorUtility.DisplayProgressBar("SceneValidator", "GetAllRootGameObjects...", (float)i / SceneManager.sceneCount);
                gameObjects.AddRange(SceneManager.GetSceneAt(i).GetRootGameObjects());
            }
            EditorUtility.ClearProgressBar();

            return gameObjects;
        }

        private static List<T> FindAllObjectsOfType<T>()
        {
            List<T> objects = new List<T>();

            List<GameObject> gameObjects = GetAllRootGameObjects();
			for (int i = 0; i < gameObjects.Count; i++)
			{
                EditorUtility.DisplayProgressBar("SceneValidator", "FindAllObjectsOfType...", (float)i / gameObjects.Count);
                objects.AddRange(gameObjects[i].GetComponentsInChildren<T>(true));
			}
            EditorUtility.ClearProgressBar();

            return objects;
        }
    }
}