test: characterize multipart generator

2026-11-13 17:04:25 +00:00 · 2026-09-02 15:20:29 +02:00
1 parent 2f4972e6fd
commit e6af4251ae
@@ -0,0 +1,130 @@
+package codechicken.multipart;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+import java.util.Arrays;
+import java.util.Set;
+import java.util.TreeSet;
+
+import org.junit.jupiter.api.Test;
+import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.Type;
+import org.objectweb.asm.tree.AbstractInsnNode;
+import org.objectweb.asm.tree.ClassNode;
+import org.objectweb.asm.tree.MethodInsnNode;
+import org.objectweb.asm.tree.MethodNode;
+
+import codechicken.multipart.asm.ScratchBitSet;
+
+class MultipartGeneratorCharacterizationTest {
+
+    private static final Set<String> FACADE = signatures(
+            "freshBitSet()Ljava/util/BitSet;",
+            "getBitSet()Ljava/util/BitSet;",
+            "registerPassThroughInterface(Ljava/lang/String;)V",
+            "registerPassThroughInterface(Ljava/lang/String;ZZ)V",
+            "registerTrait(Ljava/lang/String;Ljava/lang/String;)V",
+            "registerTrait(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)V",
+            "silentAddTile(Lnet/minecraft/world/World;Lcodechicken/lib/vec/BlockCoord;Lnet/minecraft/tileentity/TileEntity;)V");
+
+    @Test
+    void keepsExactFacadeCompanionAndScalaMapSurfaceWithoutInitializingForge() throws Exception {
+        assertEquals(FACADE, publicMethods(MultipartGenerator.class));
+        Set<String> companion = new TreeSet<>(FACADE);
+        companion.addAll(
+                signatures(
+                        "codechicken$multipart$asm$ScratchBitSet$$bitSets()Ljava/lang/ThreadLocal;",
+                        "codechicken$multipart$asm$ScratchBitSet$_setter_$codechicken$multipart$asm$ScratchBitSet$$bitSets_$eq"
+                                + "(Ljava/lang/ThreadLocal;)V",
+                        "codechicken$multipart$MultipartGenerator$$interfaceTraitMap(Z)Lscala/collection/mutable/Map;",
+                        "codechicken$multipart$MultipartGenerator$$traitsForPart(Lcodechicken/multipart/TMultiPart;Z)Ljava/util/BitSet;",
+                        "addPart(Lnet/minecraft/world/World;Lcodechicken/lib/vec/BlockCoord;Lcodechicken/multipart/TMultiPart;)"
+                                + "Lcodechicken/multipart/TileMultipart;",
+                        "generateCompositeTile(Lnet/minecraft/tileentity/TileEntity;Lscala/collection/Iterable;Z)"
+                                + "Lcodechicken/multipart/TileMultipart;",
+                        "partRemoved(Lcodechicken/multipart/TileMultipart;)Lcodechicken/multipart/TileMultipart;",
+                        "registerTileClass(Ljava/lang/Class;Ljava/util/BitSet;)V"));
+        assertEquals(companion, publicMethods(MultipartGenerator$.class));
+        for (Class<?> type : new Class<?>[] { MultipartGenerator.class, MultipartGenerator$.class }) {
+            assertTrue(Modifier.isPublic(type.getModifiers()));
+            assertTrue(Modifier.isFinal(type.getModifiers()));
+            assertSame(Object.class, type.getSuperclass());
+        }
+        assertArrayEquals(new Class<?>[] { ScratchBitSet.class }, MultipartGenerator$.class.getInterfaces());
+        assertEquals(0, MultipartGenerator.class.getDeclaredFields().length);
+        assertEquals(8, MultipartGenerator$.class.getDeclaredFields().length);
+        for (String name : new String[] { "tileTraitMap", "interfaceTraitMap_c", "interfaceTraitMap_s",
+                "partTraitMap_c", "partTraitMap_s" }) {
+            Field field = MultipartGenerator$.class.getDeclaredField(name);
+            assertSame(scala.collection.mutable.Map.class, field.getType());
+            assertEquals(Modifier.PRIVATE | Modifier.FINAL, field.getModifiers());
+        }
+        Field module = MultipartGenerator$.class.getDeclaredField("MODULE$");
+        assertSame(MultipartGenerator$.class, module.getType());
+        assertEquals(Modifier.PUBLIC | Modifier.STATIC | Modifier.FINAL, module.getModifiers());
+        assertTrue(Modifier.isPrivate(MultipartGenerator$.class.getDeclaredConstructor().getModifiers()));
+    }
+
+    @Test
+    void keepsSideSafeProxyCallbackAndCompanionOnlyGenerationCall() throws Exception {
+        assertCall(
+                MultipartGenerator$.class,
+                "registerTileClass",
+                Opcodes.INVOKEVIRTUAL,
+                "codechicken/multipart/handler/MultipartProxy$",
+                "onTileClassBuilt",
+                "(Ljava/lang/Class;)V");
+        assertCall(
+                codechicken.multipart.asm.MultipartMixinFactory$.class,
+                "onCompiled",
+                Opcodes.INVOKEVIRTUAL,
+                "codechicken/multipart/MultipartGenerator$",
+                "registerTileClass",
+                "(Ljava/lang/Class;Ljava/util/BitSet;)V");
+        assertCall(
+                MultipartHelper.class,
+                "createTileFromParts",
+                Opcodes.INVOKEVIRTUAL,
+                "codechicken/multipart/MultipartGenerator$",
+                "generateCompositeTile",
+                "(Lnet/minecraft/tileentity/TileEntity;Lscala/collection/Iterable;Z)Lcodechicken/multipart/TileMultipart;");
+    }
+
+    private static Set<String> publicMethods(Class<?> type) {
+        Set<String> result = new TreeSet<>();
+        for (Method method : type.getDeclaredMethods()) {
+            if (Modifier.isPublic(method.getModifiers()))
+                result.add(method.getName() + Type.getMethodDescriptor(method));
+        }
+        return result;
+    }
+
+    private static Set<String> signatures(String... values) {
+        return new TreeSet<>(Arrays.asList(values));
+    }
+
+    private static void assertCall(Class<?> type, String methodName, int opcode, String owner, String name,
+            String descriptor) throws Exception {
+        ClassNode node = new ClassNode();
+        new ClassReader(type.getName()).accept(node, 0);
+        for (MethodNode method : node.methods) {
+            if (!method.name.equals(methodName)) continue;
+            for (AbstractInsnNode instruction : method.instructions.toArray()) {
+                if (!(instruction instanceof MethodInsnNode)) continue;
+                MethodInsnNode call = (MethodInsnNode) instruction;
+                if (call.getOpcode() == opcode && call.owner.equals(owner)
+                        && call.name.equals(name)
+                        && call.desc.equals(descriptor))
+                    return;
+            }
+        }
+        throw new AssertionError("Missing call " + owner + '.' + name + descriptor);
+    }
+}