UnityEditor callback OnRefresh()?

As of Unity 2019 there are several options:

1) OnPostprocessAllAssets on an AssetPostprocessor fires when Ctrl+R finds an asset change, including added/deleted sprites, or code changes which trigger a compile.

 using UnityEditor;
 using UnityEngine;
 
 public class GeneralPostprocessor : AssetPostprocessor {
     static void OnPostprocessAllAssets(string[] importedAssets, string[] deletedAssets, string[] movedAssets, string[] movedFromAssetPaths) {
         Debug.Log("OnPostprocessAllAssets fired");
     }
 }
 

2) DidReloadScripts fires after Ctrl+R triggers a compile, and also when the Play button is hit. It doesn't need to be placed in an AssetPostprocessor subclass.

 [UnityEditor.Callbacks.DidReloadScripts]
 private static void OnScriptsReloaded() {
     Debug.Log("OnScriptsReloaded");
 }

3) InitializeOnLoad causes a static constructor to be called after assemblies are reloaded, which is the same behavior as DidReloadScripts (on compile and on play).

 [InitializeOnLoad]
 public class SomeClass {
     static SomeClass() {
         Debug.Log("SomeClass static constructor");
     }
 }