From ad2c1a0d3e0771352766a17f28d68d8fc59d3d0c Mon Sep 17 00:00:00 2001
From: filtered <176114999+webfiltered@users.noreply.github.com>
Date: Sat, 23 Nov 2024 13:49:13 +1100
Subject: [PATCH] Fix undo / redo filling with empty steps (#1649)

---
 src/scripts/changeTracker.ts | 18 +++++-------------
 1 file changed, 5 insertions(+), 13 deletions(-)

diff --git a/src/scripts/changeTracker.ts b/src/scripts/changeTracker.ts
index f8cced23a..f7cc309be 100644
--- a/src/scripts/changeTracker.ts
+++ b/src/scripts/changeTracker.ts
@@ -10,15 +10,7 @@ import _ from 'lodash'
 import * as jsondiffpatch from 'jsondiffpatch'
 import log from 'loglevel'
 
-function clone(obj: any) {
-  try {
-    if (typeof structuredClone !== 'undefined') {
-      return structuredClone(obj)
-    }
-  } catch (error) {
-    // structuredClone is stricter than using JSON.parse/stringify so fallback to that
-  }
-
+function clone<T>(obj: T): T {
   return JSON.parse(JSON.stringify(obj))
 }
 
@@ -69,7 +61,7 @@ export class ChangeTracker {
     if (this.restoringState) return
 
     logger.debug('Reset State')
-    this.activeState = state ?? this.activeState
+    if (state) this.activeState = clone(state)
     this.initialState = clone(this.activeState)
   }
 
@@ -112,9 +104,9 @@ export class ChangeTracker {
   checkState() {
     if (!this.app.graph || this.changeCount) return
     // @ts-expect-error zod types issue. Will be fixed after we enable ts-strict
-    const currentState = this.app.graph.serialize() as ComfyWorkflowJSON
+    const currentState = clone(this.app.graph.serialize()) as ComfyWorkflowJSON
     if (!this.activeState) {
-      this.activeState = clone(currentState)
+      this.activeState = currentState
       return
     }
     if (!ChangeTracker.graphEqual(this.activeState, currentState)) {
@@ -124,7 +116,7 @@ export class ChangeTracker {
       }
       logger.debug('Diff detected. Undo queue length:', this.undoQueue.length)
 
-      this.activeState = clone(currentState)
+      this.activeState = currentState
       this.redoQueue.length = 0
       api.dispatchEvent(
         new CustomEvent('graphChanged', { detail: this.activeState })