use interfaces from metadata instead of ClassNode in MixinPluginTransformer

Author: danyadev

gradlew

@@ -23,6 +23,7 @@
 package com.falsepattern.lib.internal.asm.transformers;
 
 import com.falsepattern.lib.internal.Tags;
+import com.falsepattern.lib.turboasm.ClassHeaderMetadata;
 import com.falsepattern.lib.turboasm.ClassNodeHandle;
 import com.falsepattern.lib.turboasm.TurboClassTransformer;
 import lombok.val;
@@ -75,17 +76,11 @@ public boolean shouldTransformClass(@NotNull String className, @NotNull ClassNod
         if (!classNode.isPresent())
             return false;
 
-        if (classNode.isOriginal()) {
-            val meta = classNode.getOriginalMetadata();
-            if (meta != null && meta.interfacesCount == 0)
-                return false;
-        }
-
-        val cn = classNode.getNode();
-        if (cn == null)
+        ClassHeaderMetadata metadata = classNode.getOriginalMetadata();
+        if (metadata == null)
             return false;
 
-        for (String i : cn.interfaces) {
+        for (String i : metadata.binaryInterfaceNames()) {
             if (IMIXINPLUGIN_INTERNAL.equals(i) || IMIXINCONFIGPLUGIN_INTERNAL.equals(i)) {
                 return true;
             }

src/main/java/com/falsepattern/lib/internal/asm/transformers/MixinPluginTransformer.java

@@ -30,6 +30,9 @@
 import java.io.ByteArrayInputStream;
 import java.io.DataInputStream;
 import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
 
 /**
  * Utilities for quickly processing class files without fully parsing them.
@@ -49,8 +52,11 @@ public final class ClassHeaderMetadata implements FastClassAccessor {
     public final int thisClassIndex;
     public final int superClassIndex;
     public final int interfacesCount;
+    public final int @NotNull [] interfaceIndices;
     public final @NotNull String binaryThisName;
     public final @Nullable String binarySuperName;
+    /** List is unmodifiable */
+    public final @NotNull List<@NotNull String> binaryInterfaceNames;
 
     /**
      * Attempts to parse a class header.
@@ -88,6 +94,9 @@ public ClassHeaderMetadata(byte @NotNull [] bytes) {
         this.thisClassIndex = u16(bytes, cpOff + Offsets.pastCpThisClassU16);
         this.superClassIndex = u16(bytes, cpOff + Offsets.pastCpSuperClassU16);
         this.interfacesCount = u16(bytes, cpOff + Offsets.pastCpInterfacesCountU16);
+        this.interfaceIndices = new int[this.interfacesCount];
+        List<String> interfaceNames = new ArrayList<>(this.interfacesCount);
+
         // Parse this&super names
         if (constantPoolEntryTypes[thisClassIndex - 1] != ConstantPoolEntryTypes.Class) {
             throw new IllegalArgumentException("This class index is not a class ref");
@@ -110,6 +119,25 @@ public ClassHeaderMetadata(byte @NotNull [] bytes) {
             }
             this.binarySuperName = modifiedUtf8(bytes, constantPoolEntryOffsets[superNameIndex - 1] + 1);
         }
+
+        // Parse interface names
+        for (int i = 0; i < this.interfacesCount; i++) {
+            final int interfaceOffset = cpOff + Offsets.pastCpInterfacesList + i * 2;
+            final int interfaceIndex = u16(bytes, interfaceOffset);
+            if (constantPoolEntryTypes[interfaceIndex - 1] != ConstantPoolEntryTypes.Class) {
+                throw new IllegalArgumentException("Interface " + i + " index is not a class ref");
+            }
+            final int interfaceNameIndex = u16(bytes, constantPoolEntryOffsets[interfaceIndex - 1] + 1);
+            if (constantPoolEntryTypes[interfaceNameIndex - 1] != ConstantPoolEntryTypes.Utf8) {
+                throw new IllegalArgumentException("Interface " + i + " index does not point to a UTF8 entry");
+            }
+            final String binaryInterfaceName =
+                    modifiedUtf8(bytes, constantPoolEntryOffsets[interfaceNameIndex - 1] + 1);
+
+            this.interfaceIndices[i] = interfaceIndex;
+            interfaceNames.add(binaryInterfaceName);
+        }
+        this.binaryInterfaceNames = Collections.unmodifiableList(interfaceNames);
     }
 
     /** Helpers to read big-endian values from class files. */
@@ -189,6 +217,8 @@ private Offsets() {}
         public static final int pastCpSuperClassU16 = pastCpThisClassU16 + 2;
         /** The value of the interfaces_count item gives the number of direct superinterfaces of this class or interface type */
         public static final int pastCpInterfacesCountU16 = pastCpSuperClassU16 + 2;
+
+        public static final int pastCpInterfacesList = pastCpInterfacesCountU16 + 2;
     }
 
     public enum ConstantPoolEntryTypes {
@@ -354,4 +384,9 @@ public boolean isEnum() {
     public @Nullable String binarySuperName() {
         return binarySuperName;
     }
-}
+
+    @Override
+    public @NotNull List<@NotNull String> binaryInterfaceNames() {
+        return binaryInterfaceNames;
+    }
+}

src/main/java/com/falsepattern/lib/turboasm/ClassHeaderMetadata.java

@@ -28,6 +28,9 @@
 import org.objectweb.asm.tree.ClassNode;
 
 import java.lang.reflect.Modifier;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
 
 /** An accessor to metadata about a class that is quickly accessible without fully parsing one. */
 public interface FastClassAccessor {
@@ -51,6 +54,9 @@ public interface FastClassAccessor {
     /** Binary (slash-separated packages) name of the super-class, null for the Object class */
     @Nullable
     String binarySuperName();
+    /** Binary (slash-separated packages) names of the implemented interfaces, list is unmodifiable */
+    @NotNull
+    List<@NotNull String> binaryInterfaceNames();
 
     static OfLoaded ofLoaded(Class<?> loadedClass) {
         return new OfLoaded(loadedClass);
@@ -111,10 +117,18 @@ public boolean isEnum() {
         public @Nullable String binarySuperName() {
             return handle.superName;
         }
+
+        @Override
+        public @NotNull List<@NotNull String> binaryInterfaceNames() {
+            return handle.interfaces == null
+                   ? Collections.emptyList()
+                   : Collections.unmodifiableList(handle.interfaces);
+        }
     }
 
     final class OfLoaded implements FastClassAccessor {
         public final Class<?> handle;
+        private @Nullable List<@NotNull String> interfacesCache = null;
 
         private OfLoaded(Class<?> handle) {
             this.handle = handle;
@@ -165,5 +179,20 @@ public boolean isEnum() {
             final Class<?> superclass = handle.getSuperclass();
             return superclass == null ? null : superclass.getName().replace('.', '/');
         }
+
+        @Override
+        public @NotNull List<@NotNull String> binaryInterfaceNames() {
+            if (interfacesCache != null) {
+                return interfacesCache;
+            }
+
+            Class<?>[] interfaces = handle.getInterfaces();
+            List<String> binaryInterfaceNames = new ArrayList<>(interfaces.length);
+            for (Class<?> iface : interfaces) {
+                binaryInterfaceNames.add(iface.getName().replace('.', '/'));
+            }
+            interfacesCache = Collections.unmodifiableList(binaryInterfaceNames);
+            return interfacesCache;
+        }
     }
-}
+}