Don't blame us forge!

- Abort loading of mixins if mod loading exceptions are present

Author: IThundxr

common/src/main/java/com/railwayteam/railways/util/MethodVarHandleUtils.java

@@ -18,23 +18,66 @@
 
 package com.railwayteam.railways.util;
 
+import com.google.common.cache.Cache;
+import com.google.common.cache.CacheBuilder;
+import org.jetbrains.annotations.Nullable;
+
 import java.lang.invoke.MethodHandles;
+import java.lang.invoke.VarHandle;
+import java.util.concurrent.ExecutionException;
 
 @SuppressWarnings("unchecked")
 public class MethodVarHandleUtils {
+    private static final Cache<VarHandleInfo, VarHandle> varHandleCache = CacheBuilder.newBuilder().build();
+
     private static final MethodHandles.Lookup lookup = MethodHandles.lookup();
-    
+
     public static <T> T getStaticField(Class<?> clazz, String fieldName, Class<T> type) throws NoSuchFieldException, IllegalAccessException {
-        return (T) lookup.findStaticVarHandle(clazz, fieldName, type).get();
+        T value = null;
+        
+        try {
+            value = (T) varHandleCache.get(
+                    new VarHandleInfo(clazz, fieldName, type),
+                    () -> lookup.findStaticVarHandle(clazz, fieldName, type)
+            ).get();
+        } catch (ExecutionException ignored) {}
+        
+        return value;
     }
 
     public static <T> T getStaticField(Class<?> clazz, String fieldName, Class<T> type, T defaultValue) {
         T returnValue = defaultValue;
-        
+
         try {
             returnValue = getStaticField(clazz, fieldName, type);
         } catch (NoSuchFieldException | IllegalAccessException ignored) {}
-        
+
         return returnValue;
     }
+
+    public static <T, U> T getPrivateField(U instance, Class<U> clazz, String fieldName, Class<T> type, T defaultValue) {
+        T returnValue = defaultValue;
+
+        VarHandle handle = findPrivateFieldVarHandle(new VarHandleInfo(clazz, fieldName, type));
+        if (handle != null) {
+            returnValue = (T) handle.get(instance);
+        }
+
+        return returnValue;
+    }
+
+    @Nullable
+    public static VarHandle findPrivateFieldVarHandle(VarHandleInfo info) {
+        try {
+            return varHandleCache.get(info, () -> {
+                MethodHandles.Lookup privateLookup = MethodHandles.privateLookupIn(info.clazz(), lookup);
+                return privateLookup.findVarHandle(info.clazz(), info.fieldName(), info.type());
+            });
+        } catch (ExecutionException ignored) {
+            return null;
+        }
+    }
+
+    public record VarHandleInfo(Class<?> clazz, String fieldName, Class<?> type) {
+    }
 }

forge/src/main/java/com/railwayteam/railways/forge/mixin/CRMixinPlugin.java

@@ -21,6 +21,9 @@
 import com.railwayteam.railways.forge.asm.ContainerLevelAccessASM;
 import com.railwayteam.railways.forge.asm.RollingModeEnumAdder;
 import com.railwayteam.railways.util.ConditionalMixinManager;
+import com.railwayteam.railways.util.MethodVarHandleUtils;
+import net.minecraftforge.fml.ModLoader;
+import net.minecraftforge.fml.ModLoadingException;
 import org.objectweb.asm.tree.ClassNode;
 import org.spongepowered.asm.mixin.extensibility.IMixinConfigPlugin;
 import org.spongepowered.asm.mixin.extensibility.IMixinInfo;
@@ -37,6 +40,16 @@ public void onLoad(String mixinPackage) { } // NO-OP
 
     @Override
     public boolean shouldApplyMixin(String targetClassName, String mixinClassName) {
+        //noinspection unchecked
+        Class<List<ModLoadingException>> modLoadingExceptionListClass = (Class<List<ModLoadingException>>)(Class<?>) List.class;
+        
+        List<ModLoadingException> modLoadingExceptionList = MethodVarHandleUtils.getPrivateField(
+                ModLoader.get(), ModLoader.class, "loadingExceptions", modLoadingExceptionListClass, null);
+        
+        if (!modLoadingExceptionList.isEmpty()) {
+            return false;
+        }
+        
         return ConditionalMixinManager.shouldApply(mixinClassName);
     }