From 8ea1742135a3199620871d4b29fba44245a5d75a Mon Sep 17 00:00:00 2001
From: Toad-Dev <748280+toad-dev@users.noreply.github.com>
Date: Mon, 7 Feb 2022 23:16:41 -0800
Subject: [PATCH] Give FakeNetworkManager a nonnull channel.

Another mod was using mixins to access this private field without any
null checking. I got the idea to use an EmbeddedChannel from Carpet,
which was having the same issue with this mod.

Fixes #53.
---
 .../fabric/mixin/ConnectionAccess.java         | 18 ++++++++++++++++++
 .../shared/util/FakeNetHandler.java            |  3 +++
 src/main/resources/computercraft.mixins.json   |  1 +
 3 files changed, 22 insertions(+)
 create mode 100644 src/main/java/dan200/computercraft/fabric/mixin/ConnectionAccess.java

diff --git a/src/main/java/dan200/computercraft/fabric/mixin/ConnectionAccess.java b/src/main/java/dan200/computercraft/fabric/mixin/ConnectionAccess.java
new file mode 100644
index 000000000..6521317cb
--- /dev/null
+++ b/src/main/java/dan200/computercraft/fabric/mixin/ConnectionAccess.java
@@ -0,0 +1,18 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2022. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+package dan200.computercraft.fabric.mixin;
+
+import io.netty.channel.Channel;
+import net.minecraft.network.Connection;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.gen.Accessor;
+
+@Mixin( Connection.class )
+public interface ConnectionAccess
+{
+    @Accessor
+    void setChannel( Channel channel );
+}
diff --git a/src/main/java/dan200/computercraft/shared/util/FakeNetHandler.java b/src/main/java/dan200/computercraft/shared/util/FakeNetHandler.java
index 1920f7f0e..9a8480852 100644
--- a/src/main/java/dan200/computercraft/shared/util/FakeNetHandler.java
+++ b/src/main/java/dan200/computercraft/shared/util/FakeNetHandler.java
@@ -6,7 +6,9 @@
 package dan200.computercraft.shared.util;
 
 import dan200.computercraft.api.turtle.FakePlayer;
+import dan200.computercraft.fabric.mixin.ConnectionAccess;
 import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.embedded.EmbeddedChannel;
 import io.netty.util.concurrent.Future;
 import io.netty.util.concurrent.GenericFutureListener;
 import net.minecraft.network.Connection;
@@ -283,6 +285,7 @@ public class FakeNetHandler extends ServerGamePacketListenerImpl
         FakeNetworkManager()
         {
             super( PacketFlow.CLIENTBOUND );
+            ((ConnectionAccess)this).setChannel( new EmbeddedChannel() );
         }
 
         @Override
diff --git a/src/main/resources/computercraft.mixins.json b/src/main/resources/computercraft.mixins.json
index b00acb4ef..f92f23b39 100644
--- a/src/main/resources/computercraft.mixins.json
+++ b/src/main/resources/computercraft.mixins.json
@@ -3,6 +3,7 @@
     "package": "dan200.computercraft.fabric.mixin",
     "compatibilityLevel": "JAVA_16",
     "mixins": [
+        "ConnectionAccess",
         "LevelResourceAccess",
         "MinecraftServerAccess",