fix: variable usage with enhanced for loop (#535) (PR #547)

jadx-core/src/main/java/jadx/core/dex/visitors/regions/LoopRegionVisitor.java

@@ -125,6 +125,7 @@ public class LoopRegionVisitor extends AbstractVisitor implements IRegionVisitor
 		// all checks passed
 		initInsn.add(AFlag.DONT_GENERATE);
 		incrInsn.add(AFlag.DONT_GENERATE);
+
 		LoopType arrForEach = checkArrayForEach(mth, loopRegion, initInsn, incrInsn, condition);
 		if (arrForEach != null) {
 			loopRegion.setType(arrForEach);
@@ -281,6 +282,8 @@ public class LoopRegionVisitor extends AbstractVisitor implements IRegionVisitor
 		}
 
 		assignInsn.add(AFlag.DONT_GENERATE);
+		assignInsn.getResult().add(AFlag.DONT_GENERATE);
+
 		for (InsnNode insnNode : toSkip) {
 			insnNode.add(AFlag.DONT_GENERATE);
 		}

jadx-core/src/main/java/jadx/core/dex/visitors/regions/variables/CollectUsageRegionVisitor.java

@@ -18,13 +18,8 @@ import jadx.core.dex.regions.loops.LoopType;
 import jadx.core.dex.visitors.regions.TracedRegionVisitor;
 
 class CollectUsageRegionVisitor extends TracedRegionVisitor {
-	private final List<RegisterArg> args;
-	private final Map<SSAVar, VarUsage> usageMap;
-
-	public CollectUsageRegionVisitor() {
-		this.usageMap = new LinkedHashMap<>();
-		this.args = new ArrayList<>();
-	}
+	private final List<RegisterArg> args = new ArrayList<>();
+	private final Map<SSAVar, VarUsage> usageMap = new LinkedHashMap<>();
 
 	public Map<SSAVar, VarUsage> getUsageMap() {
 		return usageMap;
@@ -37,9 +32,6 @@ class CollectUsageRegionVisitor extends TracedRegionVisitor {
 		int len = block.getInstructions().size();
 		for (int i = 0; i < len; i++) {
 			InsnNode insn = block.getInstructions().get(i);
-			if (insn.contains(AFlag.DONT_GENERATE)) {
-				continue;
-			}
 			processInsn(insn, usePlace);
 		}
 	}
@@ -73,11 +65,10 @@ class CollectUsageRegionVisitor extends TracedRegionVisitor {
 		args.clear();
 		insn.getRegisterArgs(args);
 		for (RegisterArg arg : args) {
-			if (arg.contains(AFlag.DONT_GENERATE)) {
-				continue;
+			if (!arg.contains(AFlag.DONT_GENERATE)) {
+				VarUsage usage = getUsage(arg.getSVar());
+				usage.getUses().add(usePlace);
 			}
-			VarUsage usage = getUsage(arg.getSVar());
-			usage.getUses().add(usePlace);
 		}
 	}
 

jadx-core/src/test/java/jadx/tests/integration/variables/TestVariables7.java → jadx-core/src/test/java/jadx/tests/integration/variables/TestVariablesUsageWithLoops.java

@@ -8,13 +8,12 @@ import java.util.List;
 
 import org.junit.jupiter.api.Test;
 
-import jadx.NotYetImplemented;
 import jadx.core.dex.nodes.ClassNode;
 import jadx.tests.api.IntegrationTest;
 
-public class TestVariables7 extends IntegrationTest {
+public class TestVariablesUsageWithLoops extends IntegrationTest {
 
-	public static class TestCls {
+	public static class TestEnhancedFor {
 
 		public void test() {
 			List list;
@@ -28,9 +27,29 @@ public class TestVariables7 extends IntegrationTest {
 	}
 
 	@Test
-	@NotYetImplemented
-	public void test() {
-		ClassNode cls = getClassNode(TestCls.class);
+	public void testEnhancedFor() {
+		ClassNode cls = getClassNode(TestEnhancedFor.class);
+		String code = cls.getCode().toString();
+
+		assertThat(code, containsString("     list = new ArrayList"));
+	}
+
+	public static class TestForLoop {
+
+		public void test() {
+			List list;
+			synchronized (this) {
+				list = new ArrayList();
+			}
+			for (int i = 0; i < list.size(); i++) {
+				System.out.println(i);
+			}
+		}
+	}
+
+	@Test
+	public void testForLoop() {
+		ClassNode cls = getClassNode(TestForLoop.class);
 		String code = cls.getCode().toString();
 
 		assertThat(code, containsString("     list = new ArrayList"));