From 16ad3bc0423795e425865d988341fa7599348dbc Mon Sep 17 00:00:00 2001
From: Karlatemp <karlatemp@vip.qq.com>
Date: Fri, 10 Sep 2021 12:55:00 +0800
Subject: [PATCH] Fix `MessageChainBuilder.copy` not copying caches

---
 .../src/commonMain/kotlin/message/data/MessageChainBuilder.kt | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mirai-core-api/src/commonMain/kotlin/message/data/MessageChainBuilder.kt b/mirai-core-api/src/commonMain/kotlin/message/data/MessageChainBuilder.kt
index e31c452f5..e89c31305 100644
--- a/mirai-core-api/src/commonMain/kotlin/message/data/MessageChainBuilder.kt
+++ b/mirai-core-api/src/commonMain/kotlin/message/data/MessageChainBuilder.kt
@@ -186,7 +186,9 @@ public class MessageChainBuilder private constructor(
      * 将所有已有元素引用复制到一个新的 [MessageChainBuilder]
      */
     public fun copy(): MessageChainBuilder {
-        return MessageChainBuilder(container.toMutableList())
+        return MessageChainBuilder(container.toMutableList()).also {
+            it.cache.append(this.cache)
+        }
     }
 
     public override fun remove(element: SingleMessage): Boolean {