Resolved Editor Script Freeze on CreateAsset with a new Material

I am having a bear of a time with Unity tonight. I'm up to over two hours and I still can't figure out how to save an material as an asset in an editor script that I have attached to an object, called on OnValidate(). If I create a material and use it, then save it, the editor freezes. All the time. Every time. If I break the script and open the project back up, the saved asset says "This is the default asset. Use assets-> Reimport...."

Code (CSharp):

1.  
2. Material UseMaterial = new Material(Shader.Find("AudioLinkSandbox/ApplySmoothText"));
3. GetComponent<MeshRenderer>().sharedMaterial = UseMaterial;
4. AssetDatabase.CreateAsset(UseMaterial, $"Assets/Compiled/cmat_{gid}.asset");
5.  

I've tried:
(1) Checking to see if I can load the asset: No. Opening the asset as material returns null.
(2) Seeing if I can search for the asset: Yes. Asset appears in AssetDatabase.FindAssets
(3) Tried guarding it with AssetDatabase.StopAssetEditing(); and AssetDatabase.StartAssetEditing();: No effect. Among many other things. And I'm out of ideas. Not exactly sure where to post about questions that are editor-script-related. P.S. This is called from within OnValidate()

(This is 2018.4.20f1)

 

This is even stranger. I start a brand new project. I create this script. I apply it to a cube. Unity Freezes.

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4. using UnityEditor;
5.  
6.  
7. public class test : MonoBehaviour
8. {
9.     public int i;
10.    
11.     void Start()
12.     {
13.        
14.     }
15.    
16.     public void OnValidate()
17.     {
18.         Material UseMaterial = new Material(Shader.Find("Standard"));
19.         UseMaterial.name = "cmat_HelloWorld";
20.         AssetDatabase.CreateAsset(UseMaterial, $"Assets/HelloWorld.mat");
21.     }
22. }
23.  

 

Solution found: Never, ever, save a material from inside OnValidate. I had to add [ExecuteInEditMode], then set a flag and did it in Update() all is well.