fix: inline anonymous classes with not default constructor (#450)

jadx-core/src/main/java/jadx/core/codegen/InsnGen.java

@@ -582,14 +582,14 @@ public class InsnGen {
 		} else {
 			parent = cls.getSuperClass();
 		}
-		MethodNode defCtr = cls.getDefaultConstructor();
-		if (defCtr != null) {
-			if (RegionUtils.notEmpty(defCtr.getRegion())) {
-				defCtr.add(AFlag.ANONYMOUS_CONSTRUCTOR);
-			} else {
-				defCtr.add(AFlag.DONT_GENERATE);
+		// hide empty anonymous constructors
+		for (MethodNode ctor : cls.getMethods()) {
+			if (ctor.contains(AFlag.ANONYMOUS_CONSTRUCTOR)
+					&& RegionUtils.isEmpty(ctor.getRegion())) {
+				ctor.add(AFlag.DONT_GENERATE);
 			}
 		}
+
 		code.add("new ");
 		if (parent == null) {
 			code.add("Object");

jadx-core/src/main/java/jadx/core/dex/nodes/ClassNode.java

@@ -34,6 +34,7 @@ import jadx.core.dex.nodes.parser.AnnotationsParser;
 import jadx.core.dex.nodes.parser.FieldInitAttr;
 import jadx.core.dex.nodes.parser.SignatureParser;
 import jadx.core.dex.nodes.parser.StaticValuesParser;
+import jadx.core.utils.RegionUtils;
 import jadx.core.utils.exceptions.DecodeException;
 import jadx.core.utils.exceptions.JadxRuntimeException;
 
@@ -124,7 +125,7 @@ public class ClassNode extends LineAttrNode implements ILoadable, ICodeNode {
 				accFlagsValue = cls.getAccessFlags();
 			}
 			this.accessFlags = new AccessInfo(accFlagsValue, AFType.CLASS);
-			markAnonymousClass(this);
+			markAnonymousClass();
 			buildCache();
 		} catch (Exception e) {
 			throw new JadxRuntimeException("Error decode class: " + clsInfo, e);
@@ -403,10 +404,25 @@ public class ClassNode extends LineAttrNode implements ILoadable, ICodeNode {
 				&& getSuperClass().getObject().equals(ArgType.ENUM.getObject());
 	}
 
+	public boolean markAnonymousClass() {
+		if (isAnonymous() || isLambdaCls()) {
+			add(AFlag.ANONYMOUS_CLASS);
+			add(AFlag.DONT_GENERATE);
+
+			for (MethodNode mth : getMethods()) {
+				if (mth.isConstructor()) {
+					mth.add(AFlag.ANONYMOUS_CONSTRUCTOR);
+				}
+			}
+			return true;
+		}
+		return false;
+	}
+
 	public boolean isAnonymous() {
 		return clsInfo.isInner()
-				&& clsInfo.getAlias().getShortName().startsWith(Consts.ANONYMOUS_CLASS_PREFIX)
-				&& getDefaultConstructor() != null;
+				&& Character.isDigit(clsInfo.getShortName().charAt(0))
+				&& methods.stream().filter(MethodNode::isConstructor).count() == 1;
 	}
 
 	public boolean isLambdaCls() {
@@ -425,13 +441,6 @@ public class ClassNode extends LineAttrNode implements ILoadable, ICodeNode {
 		return c;
 	}
 
-	private static void markAnonymousClass(ClassNode cls) {
-		if (cls.isAnonymous() || cls.isLambdaCls()) {
-			cls.add(AFlag.ANONYMOUS_CLASS);
-			cls.add(AFlag.DONT_GENERATE);
-		}
-	}
-
 	@Nullable
 	public MethodNode getClassInitMth() {
 		return searchMethodByShortId("<clinit>()V");

jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java

@@ -552,9 +552,12 @@ public class MethodNode extends LineAttrNode implements ILoadable, ICodeNode {
 		return false;
 	}
 
+	public boolean isConstructor() {
+		return accFlags.isConstructor() && mthInfo.isConstructor();
+	}
+
 	public boolean isDefaultConstructor() {
-		boolean result = false;
-		if (accFlags.isConstructor() && mthInfo.isConstructor()) {
+		if (isConstructor()) {
 			int defaultArgCount = 0;
 			// workaround for non-static inner class constructor, that has synthetic argument
 			if (parentClass.getClassInfo().isInner()
@@ -565,9 +568,9 @@ public class MethodNode extends LineAttrNode implements ILoadable, ICodeNode {
 					defaultArgCount = 1;
 				}
 			}
-			result = argsList == null || argsList.size() == defaultArgCount;
+			return argsList == null || argsList.size() == defaultArgCount;
 		}
-		return result;
+		return false;
 	}
 
 	public boolean isVirtual() {

jadx-core/src/main/java/jadx/core/dex/visitors/ClassModifier.java

@@ -51,10 +51,11 @@ public class ClassModifier extends AbstractVisitor {
 			cls.add(AFlag.DONT_GENERATE);
 			return false;
 		}
-		markAnonymousClass(cls);
+		cls.markAnonymousClass();
 		removeSyntheticFields(cls);
 		cls.getMethods().forEach(ClassModifier::removeSyntheticMethods);
 		cls.getMethods().forEach(ClassModifier::removeEmptyMethods);
+		cls.getMethods().forEach(ClassModifier::cleanInsnsInAnonymousConstructor);
 		return false;
 	}
 
@@ -65,13 +66,6 @@ public class ClassModifier extends AbstractVisitor {
 				&& cls.getInnerClasses().isEmpty();
 	}
 
-	private void markAnonymousClass(ClassNode cls) {
-		if (cls.isAnonymous()) {
-			cls.add(AFlag.ANONYMOUS_CLASS);
-			cls.add(AFlag.DONT_GENERATE);
-		}
-	}
-
 	/**
 	 * Remove synthetic fields if type is outer class or class will be inlined (anonymous)
 	 */
@@ -324,12 +318,37 @@ public class ClassModifier extends AbstractVisitor {
 		}
 	}
 
+	/**
+	 * Remove super call and put into removed fields from anonymous constructor
+	 */
+	private static void cleanInsnsInAnonymousConstructor(MethodNode mth) {
+		if (!mth.contains(AFlag.ANONYMOUS_CONSTRUCTOR)) {
+			return;
+		}
+		for (BlockNode block : mth.getBasicBlocks()) {
+			for (InsnNode insn : block.getInstructions()) {
+				InsnType type = insn.getType();
+				if (type == InsnType.CONSTRUCTOR) {
+					ConstructorInsn ctorInsn = (ConstructorInsn) insn;
+					if (ctorInsn.isSuper()) {
+						ctorInsn.add(AFlag.DONT_GENERATE);
+					}
+				} else if (type == InsnType.IPUT) {
+					FieldInfo fldInfo = (FieldInfo) ((IndexInsnNode) insn).getIndex();
+					FieldNode fieldNode = mth.dex().resolveField(fldInfo);
+					if (fieldNode != null && fieldNode.contains(AFlag.DONT_GENERATE)) {
+						insn.add(AFlag.DONT_GENERATE);
+					}
+				}
+			}
+		}
+	}
+
 	private static boolean isNonDefaultConstructorExists(MethodNode defCtor) {
 		ClassNode parentClass = defCtor.getParentClass();
 		for (MethodNode mth : parentClass.getMethods()) {
 			if (mth != defCtor
-					&& mth.getAccessFlags().isConstructor()
-					&& mth.getMethodInfo().isConstructor()
+					&& mth.isConstructor()
 					&& !mth.isDefaultConstructor()) {
 				return true;
 			}

jadx-core/src/main/java/jadx/core/dex/visitors/ModVisitor.java

@@ -11,7 +11,6 @@ import org.slf4j.LoggerFactory;
 import jadx.core.dex.attributes.AFlag;
 import jadx.core.dex.attributes.AType;
 import jadx.core.dex.attributes.nodes.FieldReplaceAttr;
-import jadx.core.dex.info.ClassInfo;
 import jadx.core.dex.info.FieldInfo;
 import jadx.core.dex.info.MethodInfo;
 import jadx.core.dex.instructions.ArithNode;
@@ -39,8 +38,8 @@ import jadx.core.dex.trycatch.ExcHandlerAttr;
 import jadx.core.dex.trycatch.ExceptionHandler;
 import jadx.core.dex.visitors.shrink.CodeShrinkVisitor;
 import jadx.core.utils.ErrorsCounter;
-import jadx.core.utils.InsnUtils;
 import jadx.core.utils.InsnRemover;
+import jadx.core.utils.InsnUtils;
 import jadx.core.utils.exceptions.JadxRuntimeException;
 
 import static jadx.core.utils.BlockUtils.replaceInsn;
@@ -207,23 +206,22 @@ public class ModVisitor extends AbstractVisitor {
 		if (callMthNode == null) {
 			return;
 		}
-		ClassNode classNode = callMthNode.getParentClass();
-		ClassInfo classInfo = classNode.getClassInfo();
-		ClassNode parentClass = mth.getParentClass();
-		if (!classInfo.isInner()
-				|| !Character.isDigit(classInfo.getShortName().charAt(0))
-				|| !parentClass.getInnerClasses().contains(classNode)) {
-			return;
-		}
-		// TODO: calculate this constructor and other constructor usage
 		Map<InsnArg, FieldNode> argsMap = getArgsToFieldsMapping(callMthNode, co);
 		if (argsMap.isEmpty() && !callMthNode.getArguments(true).isEmpty()) {
 			return;
 		}
 
-		// all checks passed
-		classNode.add(AFlag.ANONYMOUS_CLASS);
-		callMthNode.add(AFlag.DONT_GENERATE);
+		ClassNode classNode = callMthNode.getParentClass();
+		if (!classNode.contains(AFlag.ANONYMOUS_CLASS)) {
+			// check if class can be anonymous but not yet marked due to dependency issues
+			if (!classNode.markAnonymousClass()) {
+				return;
+			}
+		}
+		if (!mth.getParentClass().getInnerClasses().contains(classNode)) {
+			return;
+		}
+
 		for (Map.Entry<InsnArg, FieldNode> entry : argsMap.entrySet()) {
 			FieldNode field = entry.getValue();
 			if (field == null) {

jadx-core/src/main/java/jadx/core/utils/RegionUtils.java

@@ -7,6 +7,7 @@ import java.util.Set;
 
 import org.jetbrains.annotations.Nullable;
 
+import jadx.core.dex.attributes.AFlag;
 import jadx.core.dex.attributes.AType;
 import jadx.core.dex.attributes.AttrList;
 import jadx.core.dex.attributes.nodes.LoopInfo;
@@ -195,7 +196,13 @@ public class RegionUtils {
 			return false;
 		}
 		if (container instanceof IBlock) {
-			return !((IBlock) container).getInstructions().isEmpty();
+			List<InsnNode> insnList = ((IBlock) container).getInstructions();
+			for (InsnNode insnNode : insnList) {
+				if (!insnNode.contains(AFlag.DONT_GENERATE)) {
+					return true;
+				}
+			}
+			return false;
 		} else if (container instanceof IRegion) {
 			IRegion region = (IRegion) container;
 			for (IContainer block : region.getSubBlocks()) {

jadx-core/src/test/java/jadx/tests/integration/inner/TestAnonymousClass14.java

@@ -0,0 +1,58 @@
+package jadx.tests.integration.inner;
+
+import org.junit.jupiter.api.Test;
+
+import jadx.core.dex.nodes.ClassNode;
+import jadx.tests.api.SmaliTest;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.not;
+
+public class TestAnonymousClass14 extends SmaliTest {
+
+	/*
+		public class OuterCls implements Runnable {
+			class AnonymousClass1 {
+				AnonymousClass1(Runnable runnable) {
+				}
+
+				public void someMethod() {
+				}
+			}
+
+			class TestCls {
+				private TestCls() {
+					ArrayList arrayList = new ArrayList();
+				}
+
+				synthetic TestCls(OuterCls outerCls, AnonymousClass1 anonymousClass1) {
+					this();
+				}
+			}
+
+			public void makeAnonymousCls() {
+				AnonymousClass1 anonymousClass1 = new AnonymousClass1(this);
+			}
+
+			public void makeTestCls() {
+				TestCls testCls = new TestCls(this, null);
+			}
+
+			public void run() {
+			}
+
+			public void use(AnonymousClass1 anonymousClass1) {
+			}
+		}
+	 */
+
+	@Test
+	public void test() {
+		ClassNode clsNode = getClassNodeFromSmaliFiles("inner", "TestAnonymousClass14", "OuterCls");
+		String code = clsNode.getCode().toString();
+
+		assertThat(code, not(containsString("AnonymousClass1")));
+		assertThat(code, not(containsString("synthetic")));
+	}
+}

jadx-core/src/test/java/jadx/tests/integration/inner/TestAnonymousClass15.java

@@ -0,0 +1,48 @@
+package jadx.tests.integration.inner;
+
+import org.junit.jupiter.api.Test;
+
+import jadx.NotYetImplemented;
+import jadx.core.dex.nodes.ClassNode;
+import jadx.tests.api.IntegrationTest;
+
+import static jadx.tests.api.utils.JadxMatchers.containsOne;
+import static jadx.tests.api.utils.JadxMatchers.countString;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+public class TestAnonymousClass15 extends IntegrationTest {
+
+	public static class TestCls {
+
+		public Thread test(Runnable run) {
+			return new Thread(run) {
+				@Override
+				public void run() {
+					System.out.println("run");
+					super.run();
+				}
+			};
+		}
+
+		public Thread test2(Runnable run) {
+			return new Thread(run) {
+				{
+					setName("run");
+				}
+
+				@Override
+				public void run() {
+				}
+			};
+		}
+	}
+
+	@Test
+	public void test() {
+		ClassNode classNode = getClassNode(TestCls.class);
+		String code = classNode.getCode().toString();
+
+		assertThat(code, countString(2, "return new Thread(run) {"));
+		assertThat(code, containsOne("setName(\"run\");"));
+	}
+}

jadx-core/src/test/smali/inner/TestAnonymousClass14/OuterCls$1.smali

@@ -0,0 +1,28 @@
+.class Linner/OuterCls$1;
+.super Ljava/lang/Thread;
+.source "SourceFile"
+
+.annotation system Ldalvik/annotation/InnerClass;
+    accessFlags = 0x0
+    name = null
+.end annotation
+
+.field final synthetic this$0:Linner/OuterCls;
+
+
+# direct methods
+.method constructor <init>(Linner/OuterCls;Ljava/lang/Runnable;)V
+    .locals 0
+
+    iput-object p1, p0, Linner/OuterCls$1;->this$0:Linner/OuterCls;
+
+    return-void
+.end method
+
+
+# virtual methods
+.method public someMethod()V
+    .locals 3
+
+    return-void
+.end method

jadx-core/src/test/smali/inner/TestAnonymousClass14/OuterCls$TestCls.smali

@@ -0,0 +1,39 @@
+.class Linner/OuterCls$TestCls;
+.super Ljava/lang/Object;
+.source "SourceFile"
+
+
+# annotations
+.annotation system Ldalvik/annotation/EnclosingClass;
+    value = Linner/OuterCls;
+.end annotation
+
+.annotation system Ldalvik/annotation/InnerClass;
+    accessFlags = 0x0
+    name = "TestCls"
+.end annotation
+
+.field final synthetic this$0:Linner/OuterCls;
+
+
+# direct methods
+.method private constructor <init>(Linner/OuterCls;)V
+    .locals 0
+
+    iput-object p1, p0, Linner/OuterCls$TestCls;->this$0:Linner/OuterCls;
+
+    new-instance p1, Ljava/util/ArrayList;
+
+    invoke-direct {p1}, Ljava/util/ArrayList;-><init>()V
+
+    return-void
+.end method
+
+.method synthetic constructor <init>(Linner/OuterCls;Linner/OuterCls$1;)V
+    .locals 0
+
+    invoke-direct {p0, p1}, Linner/OuterCls$TestCls;-><init>(Linner/OuterCls;)V
+
+    return-void
+.end method
+

jadx-core/src/test/smali/inner/TestAnonymousClass14/OuterCls.smali

@@ -0,0 +1,65 @@
+.class public Linner/OuterCls;
+.super Ljava/lang/Object;
+.source "SourceFile"
+
+# interfaces
+.implements Ljava/lang/Runnable;
+
+
+# annotations
+.annotation system Ldalvik/annotation/MemberClasses;
+    value = {
+        Linner/OuterCls$TestCls;
+    }
+.end annotation
+
+
+# direct methods
+.method static constructor <clinit>()V
+    .locals 0
+
+    return-void
+.end method
+
+.method public constructor <init>()V
+    .locals 1
+
+    return-void
+.end method
+
+.method public makeTestCls()V
+    .locals 2
+
+    new-instance v1, Linner/OuterCls$TestCls;
+
+    const/4 v0, 0x0
+
+    invoke-direct {v1, p0, v0}, Linner/OuterCls$TestCls;-><init>(Linner/OuterCls;Linner/OuterCls$1;)V
+
+    return-void
+.end method
+
+.method public makeAnonymousCls()V
+    .locals 2
+
+    new-instance v1, Linner/OuterCls$1;
+
+    invoke-direct {v1, p0, p0}, Linner/OuterCls$1;-><init>(Linner/OuterCls;Ljava/lang/Runnable;)V
+
+    invoke-direct {p0, v1}, Linner/OuterCls;->use(Ljava/lang/Thread;)V
+
+    return-void
+.end method
+
+.method public run()V
+    .locals 2
+
+    return-void
+.end method
+
+.method public use(Ljava/lang/Thread;)V
+    .locals 2
+
+    return-void
+.end method
+