module-project-validator/Editor/Validators/Assets/AssetValidatorMaterialTexture.cs

using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Rendering;

namespace Module.ProjectValidator.Editor
{
    internal sealed class AssetValidatorMaterialTexture : IAssetValidator<Material>
    {
        public void Validate(Material obj, List<ValidatorResult> results)
        {
            if (obj.shader == null)
                return;

            var count = obj.shader.GetPropertyCount();

            for (var i = 0; i < count; i++)
            {
                var propertyType = obj.shader.GetPropertyType(i);
                
                if (propertyType != ShaderPropertyType.Texture)
                    continue;
                
                var propertyName = obj.shader.GetPropertyName(i);
                var propertyValue = obj.GetTexture(propertyName);
                
                if (propertyValue == null)
                    results.Add(ValidatorResult.Create(EValidatorSeverity.Warning, $"Texture property '{propertyName}' is Null"));
            }
        }
    }
}