fix: correct method arg name if unused

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

@@ -238,10 +238,11 @@ public class MethodGen {
 				classGen.useType(code, argType);
 			}
 			code.add(' ');
-			if (code.isMetadataSupported() && ssaVar != null) {
+			String varName = nameGen.assignArg(var);
+			if (code.isMetadataSupported() && ssaVar != null /* for fallback mode */) {
 				code.attachDefinition(VarDeclareRef.get(mth, var));
 			}
-			code.add(nameGen.assignArg(var));
+			code.add(varName);
 
 			i++;
 			if (it.hasNext()) {

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

@@ -99,9 +99,6 @@ public class MethodNode extends NotificationAttrNode implements IMethodDetails,
 	@Override
 	public void unload() {
 		loaded = false;
-		if (noCode) {
-			return;
-		}
 		// don't unload retType, argTypes, typeParameters
 		thisArg = null;
 		argsList = null;

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

@@ -26,9 +26,6 @@ public class InitCodeVariables extends AbstractVisitor {
 
 	@Override
 	public void visit(MethodNode mth) throws JadxException {
-		if (mth.isNoCode()) {
-			return;
-		}
 		initCodeVars(mth);
 	}
 
@@ -42,16 +39,24 @@ public class InitCodeVariables extends AbstractVisitor {
 	private static void initCodeVars(MethodNode mth) {
 		RegisterArg thisArg = mth.getThisArg();
 		if (thisArg != null) {
-			initCodeVar(thisArg.getSVar());
+			initCodeVar(mth, thisArg);
 		}
 		for (RegisterArg mthArg : mth.getArgRegs()) {
-			initCodeVar(mthArg.getSVar());
+			initCodeVar(mth, mthArg);
 		}
 		for (SSAVar ssaVar : mth.getSVars()) {
 			initCodeVar(ssaVar);
 		}
 	}
 
+	public static void initCodeVar(MethodNode mth, RegisterArg regArg) {
+		SSAVar ssaVar = regArg.getSVar();
+		if (ssaVar == null) {
+			ssaVar = mth.makeNewSVar(regArg);
+		}
+		initCodeVar(ssaVar);
+	}
+
 	public static void initCodeVar(SSAVar ssaVar) {
 		if (ssaVar.isCodeVarSet()) {
 			return;

jadx-core/src/test/java/jadx/tests/integration/variables/TestVariablesDeclAnnotation.java

+package jadx.tests.integration.variables;
+
+import java.util.Comparator;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.junit.jupiter.api.Test;
+
+import jadx.api.data.annotations.VarDeclareRef;
+import jadx.core.dex.nodes.ClassNode;
+import jadx.core.dex.nodes.MethodNode;
+import jadx.tests.api.IntegrationTest;
+
+import static jadx.tests.api.utils.assertj.JadxAssertions.assertThat;
+
+public class TestVariablesDeclAnnotation extends IntegrationTest {
+
+	public abstract static class TestCls {
+		public int test(String str, int i) {
+			return i;
+		}
+
+		public abstract int test2(String str);
+	}
+
+	@Test
+	public void test() {
+		noDebugInfo();
+		ClassNode cls = getClassNode(TestCls.class);
+		assertThat(cls).code()
+				.containsOne("public int test(String str, int i) {")
+				.containsOne("public abstract int test2(String str);");
+
+		checkArgNamesInMethod(cls, "test", "[str, i]");
+		checkArgNamesInMethod(cls, "test2", "[str]");
+	}
+
+	private static void checkArgNamesInMethod(ClassNode cls, String mthName, String expectedVars) {
+		MethodNode testMth = cls.searchMethodByShortName(mthName);
+		assertThat(testMth).isNotNull();
+
+		int mthLine = testMth.getDecompiledLine();
+		List<String> argNames = cls.getCode().getAnnotations().entrySet().stream()
+				.filter(e -> e.getKey().getLine() == mthLine && e.getValue() instanceof VarDeclareRef)
+				.sorted(Comparator.comparingInt(e -> e.getKey().getPos()))
+				.map(e -> ((VarDeclareRef) e.getValue()).getName())
+				.collect(Collectors.toList());
+
+		assertThat(argNames).doesNotContainNull();
+		assertThat(argNames.toString()).isEqualTo(expectedVars);
+	}
+}