From 395e14ba9baee50d084e0f06f3ba941aff52be9b Mon Sep 17 00:00:00 2001
From: embeddedt <42941056+embeddedt@users.noreply.github.com>
Date: Sat, 8 Apr 2023 19:08:03 -0400
Subject: [PATCH] Fix leaking mixin injectors

---
 .../modernfix/core/ModernFixMixinPlugin.java  |  15 ++
 .../embeddedt/modernfix/util/DummyList.java   | 131 ++++++++++++++++++
 2 files changed, 146 insertions(+)
 create mode 100644 src/main/java/org/embeddedt/modernfix/util/DummyList.java

diff --git a/src/main/java/org/embeddedt/modernfix/core/ModernFixMixinPlugin.java b/src/main/java/org/embeddedt/modernfix/core/ModernFixMixinPlugin.java
index 37c436a7..0c22fd8d 100644
--- a/src/main/java/org/embeddedt/modernfix/core/ModernFixMixinPlugin.java
+++ b/src/main/java/org/embeddedt/modernfix/core/ModernFixMixinPlugin.java
@@ -10,9 +10,12 @@ import org.apache.logging.log4j.Logger;
 import org.embeddedt.modernfix.classloading.ModernFixResourceFinder;
 import org.embeddedt.modernfix.core.config.ModernFixEarlyConfig;
 import org.embeddedt.modernfix.core.config.Option;
+import org.embeddedt.modernfix.util.DummyList;
 import org.objectweb.asm.tree.*;
 import org.spongepowered.asm.mixin.extensibility.IMixinConfigPlugin;
 import org.spongepowered.asm.mixin.extensibility.IMixinInfo;
+import org.spongepowered.asm.mixin.injection.struct.InjectionInfo;
+import org.spongepowered.asm.mixin.injection.struct.InjectorGroupInfo;
 
 import java.io.File;
 import java.io.IOException;
@@ -72,6 +75,18 @@ public class ModernFixMixinPlugin implements IMixinConfigPlugin {
         } catch(RuntimeException | ReflectiveOperationException e) {
             logger.error("Failed to make classloading changes", e);
         }
+
+        /* https://github.com/FabricMC/Mixin/pull/99 */
+        try {
+            Field groupMembersField = InjectorGroupInfo.class.getDeclaredField("members");
+            groupMembersField.setAccessible(true);
+            Field noGroupField = InjectorGroupInfo.Map.class.getDeclaredField("NO_GROUP");
+            noGroupField.setAccessible(true);
+            InjectorGroupInfo noGroup = (InjectorGroupInfo)noGroupField.get(null);
+            groupMembersField.set(noGroup, new DummyList<>());
+        } catch(RuntimeException | ReflectiveOperationException e) {
+            logger.error("Failed to patch mixin memory leak", e);
+        }
     }
 
     private Method defineClassMethod = null;
diff --git a/src/main/java/org/embeddedt/modernfix/util/DummyList.java b/src/main/java/org/embeddedt/modernfix/util/DummyList.java
new file mode 100644
index 00000000..221c6506
--- /dev/null
+++ b/src/main/java/org/embeddedt/modernfix/util/DummyList.java
@@ -0,0 +1,131 @@
+package org.embeddedt.modernfix.util;
+
+import org.jetbrains.annotations.NotNull;
+
+import java.util.*;
+
+/**
+ * List with no-op methods.
+ */
+public class DummyList<T> implements List<T> {
+    @Override
+    public int size() {
+        return 0;
+    }
+
+    @Override
+    public boolean isEmpty() {
+        return true;
+    }
+
+    @Override
+    public boolean contains(Object o) {
+        return false;
+    }
+
+    @NotNull
+    @Override
+    public Iterator<T> iterator() {
+        return Collections.emptyIterator();
+    }
+
+    @NotNull
+    @Override
+    public Object[] toArray() {
+        return new Object[0];
+    }
+
+    @NotNull
+    @Override
+    public <T1> T1[] toArray(@NotNull T1[] t1s) {
+        return Arrays.copyOf(t1s, 0);
+    }
+
+    @Override
+    public boolean add(T t) {
+        return false;
+    }
+
+    @Override
+    public boolean remove(Object o) {
+        return false;
+    }
+
+    @Override
+    public boolean containsAll(@NotNull Collection<?> collection) {
+        return false;
+    }
+
+    @Override
+    public boolean addAll(@NotNull Collection<? extends T> collection) {
+        return false;
+    }
+
+    @Override
+    public boolean addAll(int i, @NotNull Collection<? extends T> collection) {
+        return false;
+    }
+
+    @Override
+    public boolean removeAll(@NotNull Collection<?> collection) {
+        return false;
+    }
+
+    @Override
+    public boolean retainAll(@NotNull Collection<?> collection) {
+        return false;
+    }
+
+    @Override
+    public void clear() {
+
+    }
+
+    @Override
+    public T get(int i) {
+        return null;
+    }
+
+    @Override
+    public T set(int i, T t) {
+        return null;
+    }
+
+    @Override
+    public void add(int i, T t) {
+
+    }
+
+    @Override
+    public T remove(int i) {
+        return null;
+    }
+
+    @Override
+    public int indexOf(Object o) {
+        return -1;
+    }
+
+    @Override
+    public int lastIndexOf(Object o) {
+        return -1;
+    }
+
+    @NotNull
+    @Override
+    public ListIterator<T> listIterator() {
+        return Collections.emptyListIterator();
+    }
+
+    @NotNull
+    @Override
+    public ListIterator<T> listIterator(int i) {
+        return Collections.emptyListIterator();
+    }
+
+    @NotNull
+    @Override
+    public List<T> subList(int i, int i1) {
+        return new DummyList<>();
+    }
+}