Enumの範囲を指定するやつ

EnumRangeAttribute.cs

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

[AttributeUsage(AttributeTargets.Field | AttributeTargets.Enum, AllowMultiple = true)]
public class EnumRangeAttribute : PropertyAttribute
{
    public Type Type { get; private set; }
    public int Min { get; private set; }
    public int Max { get; private set; }

    public EnumRangeAttribute(Type selfType, int min, int max)
    {
        Type = selfType;
        Min = min;
        Max = max;
    }
}

#if UNITY_EDITOR
[CustomPropertyDrawer(typeof(EnumRangeAttribute))]
public class EnumAttributeDrawer : PropertyDrawer
{
    public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
    {
        if (!(attribute is EnumRangeAttribute attr))
        {
            return;
        }
        
        //指定された範囲内のEnum要素とEnumメンバ
        var enumName = new List<string>();
        var enumMembers = new List<int>();
        for (int i = attr.Min; i < attr.Max; i++)
        {
            if (!Enum.IsDefined(attr.Type, i)) continue;
            enumName.Add(Enum.GetName(attr.Type, i));
            enumMembers.Add(i);
        }
        
        //描画する
        property.intValue = EditorGUI.IntPopup(position, property.displayName, property.intValue,
            enumName.ToArray(), enumMembers.ToArray());
        
    }
}
#endif

こんな感じ↓の列挙型に対して
enum Hoge
{
FugaStart=0,
FugaValue
FugaValueValue,
FugaEnd,

 XXXStart=10,
 XXXValue,
 XXXValueValue,
 XXXEnd

}

[EnumRange(typeof(Hoge), (int) Hoge.FugaStart + 1, (int) Hoge.FugaEnd)]
public Hoge hoge;

みたいに指定してあげると便利、かも