From 0c5ced1bbf91450024436573f16da8177b684c13 Mon Sep 17 00:00:00 2001
From: cpw <cpw+github@weeksfamily.ca>
Date: Fri, 13 Nov 2020 20:41:20 -0500
Subject: [PATCH] Fix NPE problem when modid is mismatched.

Signed-off-by: cpw <cpw+github@weeksfamily.ca>
---
 .../java/net/minecraftforge/fml/ModContainer.java     | 10 ++++++++++
 src/main/java/net/minecraftforge/fml/ModLoader.java   | 11 ++++++-----
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/src/main/java/net/minecraftforge/fml/ModContainer.java b/src/main/java/net/minecraftforge/fml/ModContainer.java
index 681284874..4456c9482 100644
--- a/src/main/java/net/minecraftforge/fml/ModContainer.java
+++ b/src/main/java/net/minecraftforge/fml/ModContainer.java
@@ -75,6 +75,16 @@ public abstract class ModContainer
                 (incoming, isNetwork)->Objects.equals(incoming, this.modInfo.getVersion().toString())));
     }
 
+    /**
+     * Errored container state, used for filtering. Does nothing.
+     */
+    ModContainer()
+    {
+        this.modLoadingStage = ModLoadingStage.ERROR;
+        modId = "BROKEN";
+        namespace = "BROKEN";
+        modInfo = null;
+    }
     /**
      * @return the modid for this mod
      */
diff --git a/src/main/java/net/minecraftforge/fml/ModLoader.java b/src/main/java/net/minecraftforge/fml/ModLoader.java
index cdd724710..fa69954bf 100644
--- a/src/main/java/net/minecraftforge/fml/ModLoader.java
+++ b/src/main/java/net/minecraftforge/fml/ModLoader.java
@@ -33,6 +33,7 @@ import net.minecraftforge.fml.loading.LoadingModList;
 import net.minecraftforge.fml.loading.moddiscovery.InvalidModIdentifier;
 import net.minecraftforge.fml.loading.moddiscovery.ModFile;
 import net.minecraftforge.fml.loading.moddiscovery.ModFileInfo;
+import net.minecraftforge.fml.loading.moddiscovery.ModInfo;
 import net.minecraftforge.fml.loading.progress.StartupMessageManager;
 import net.minecraftforge.fml.network.FMLNetworkConstants;
 import net.minecraftforge.fml.network.NetworkRegistry;
@@ -282,7 +283,7 @@ public class ModLoader
             loadingExceptions.add(new ModLoadingException(null, ModLoadingStage.CONSTRUCT, "fml.modloading.missingclasses", null, modFile.getFilePath()));
         }
         // remove errored mod containers
-        return containers.stream().filter(obj -> !(obj instanceof ErroredModContainer)).collect(Collectors.toList());
+        return containers.stream().filter(mc -> mc.modLoadingStage != ModLoadingStage.ERROR).collect(Collectors.toList());
     }
 
     private ModContainer buildModContainerFromTOML(final ModFile modFile, final TransformingClassLoader modClassLoader, final Map<String, IModInfo> modInfoMap, final Map.Entry<String, ? extends IModLanguageProvider.IModLanguageLoader> idToProviderEntry) {
@@ -297,7 +298,7 @@ public class ModLoader
             // exceptions are caught and added to the error list for later handling
             loadingExceptions.add(mle);
             // return an errored container instance here, because we tried and failed building a container.
-            return new ErroredModContainer(mle);
+            return new ErroredModContainer();
         }
     }
 
@@ -341,9 +342,9 @@ public class ModLoader
         return runningDataGen;
     }
 
-    static class ErroredModContainer extends ModContainer {
-        public ErroredModContainer(final ModLoadingException mle) {
-            super(mle.getModInfo());
+    private static class ErroredModContainer extends ModContainer {
+        public ErroredModContainer() {
+            super();
         }
 
         @Override