From cc4f4df4f95b57fa0633fe2fb881059e64dba288 Mon Sep 17 00:00:00 2001
From: Lucien Greathouse <me@lpghatguy.com>
Date: Sat, 16 Jan 2021 18:26:30 -0700
Subject: [PATCH] Support changing ClassName in Reconciler.diff

---
 plugin/src/Reconciler/diff.lua | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/plugin/src/Reconciler/diff.lua b/plugin/src/Reconciler/diff.lua
index 67c8c161..d146b308 100644
--- a/plugin/src/Reconciler/diff.lua
+++ b/plugin/src/Reconciler/diff.lua
@@ -52,8 +52,9 @@ local function diff(instanceMap, virtualInstances, rootId)
 			invariant("Cannot diff an instance not present in InstanceMap\nID: {}", id)
 		end
 
+		local changedClassName = nil
 		if virtualInstance.ClassName ~= instance.ClassName then
-			error("unimplemented: support changing ClassName")
+			changedClassName = virtualInstance.ClassName
 		end
 
 		local changedName = nil
@@ -89,11 +90,11 @@ local function diff(instanceMap, virtualInstances, rootId)
 			end
 		end
 
-		if changedName ~= nil or not isEmpty(changedProperties) then
+		if changedName ~= nil or changedClassName ~= nil or not isEmpty(changedProperties) then
 			table.insert(patch.updated, {
 				id = id,
 				changedName = changedName,
-				changedClassName = nil,
+				changedClassName = changedClassName,
 				changedProperties = changedProperties,
 				changedMetadata = nil,
 			})