fix: CVRAvatar prevents removal of Animator (#260)

* fix: CVRAvatar prevents removal of Animator
The error "Can't remove Animator because CVRAvatar (Script) depends on it" occurs in ChilloutVR avatars during the recreation of the Animator component.
This is because CVRAvatar has a RequireComponent annotation for Animator.
This commit fixes this issue by removing CVRAvatar first, and recreates it in the same way.

Tested on ChilloutVR CCK v3.9 RELEASE

* review pass: introspect RequireComponent attribute instead

* chore: update CHANGELOG.md

---------

Co-authored-by: Haï~ <hai-vr@users.noreply.github.com>
Co-authored-by: bd_ <bd_@nadena.dev>

CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 
 - [#257] Proxy renderers no longer appear in the hierarchy.
+- [#260] [ChilloutVR] Fix: Build fails due to CVRAvatar preventing recreation of Animator (contributed by @hai-vr)
 
 ### Changed
 

Editor/ApplyOnPlay.cs

@@ -27,6 +27,7 @@
 #region
 
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using nadena.dev.ndmf.config;
 using nadena.dev.ndmf.runtime;
@@ -135,19 +136,56 @@ private static void RecreateAnimators(Transform avatar)
                 var tmpAnimator = tmpObject.AddComponent<Animator>();
                 bool enabled = animator.enabled;
 
+                // Support components that need to be destroyed before the Animator is destroyed,
+                // such as ChilloutVR's CVRAvatar component.
+                var tmpComponentsRequiringAnimator = new List<Component>();
+                foreach (var componentRequiringAnimator in FindSiblingComponentsRequiringAnimator(animator))
+                {
+                    var tmpComponentRequiringAnimator = tmpObject.AddComponent(componentRequiringAnimator.GetType());
+                    tmpComponentsRequiringAnimator.Add(tmpComponentRequiringAnimator);
+                    EditorUtility.CopySerialized(componentRequiringAnimator, tmpComponentRequiringAnimator);
+                    // Destroy this first before destroying the Animator below.
+                    UnityObject.DestroyImmediate(componentRequiringAnimator);
+                }
+
                 EditorUtility.CopySerialized(animator, tmpAnimator);
                 UnityObject.DestroyImmediate(animator);
                 var newAnimator = obj.AddComponent<Animator>();
                 newAnimator.enabled = false;
                 EditorUtility.CopySerialized(tmpAnimator, newAnimator);
                 newAnimator.enabled = enabled;
+
+                foreach (var tmpComponentRequiringAnimator in tmpComponentsRequiringAnimator)
+                {
+                    var newComponent = obj.AddComponent(tmpComponentRequiringAnimator.GetType());
+                    EditorUtility.CopySerialized(tmpComponentRequiringAnimator, newComponent);
+                    // Even in the temporary object, destroy this first before destroying the Animator below.
+                    UnityObject.DestroyImmediate(tmpComponentRequiringAnimator);
+                }
 
                 UnityObject.DestroyImmediate(tmpAnimator);
             }
 
             UnityObject.DestroyImmediate(tmpObject);
         }
-
+
+        private static IEnumerable<Component> FindSiblingComponentsRequiringAnimator(Animator animator)
+        {
+            return animator.GetComponents<Component>()
+                // GetComponents may return null elements on unloaded MonoBehaviour scripts
+                .Where(component => component != null)
+                .Where(component =>
+                {
+                    var requiresAnimator = component.GetType()
+                        .GetCustomAttributes(typeof(RequireComponent), true)
+                        .Cast<RequireComponent>()
+                        .Any(requireComponent => requireComponent.m_Type0 == typeof(Animator)
+                                                 || requireComponent.m_Type1 == typeof(Animator)
+                                                 || requireComponent.m_Type2 == typeof(Animator));
+                    return requiresAnimator;
+                });
+        }
+
         private static void OnPlayModeStateChanged(PlayModeStateChange obj)
         {
             if (obj == PlayModeStateChange.EnteredPlayMode)