From f02a33ace3b451420c2a7113840c2a514133644d Mon Sep 17 00:00:00 2001
From: Skylot <skylot@gmail.com>
Date: Wed, 19 Jun 2019 20:38:50 +0300
Subject: [PATCH] fix: ignore NOPs in try-catch (#668)

---
 .../java/jadx/core/dex/nodes/MethodNode.java  |  7 ++--
 .../test/java/jadx/tests/api/SmaliTest.java   |  7 ++++
 .../trycatch/TestTryCatchLastInsn.java        | 35 +++++++++++++++++++
 .../smali/trycatch/TestTryCatchLastInsn.smali | 34 ++++++++++++++++++
 4 files changed, 79 insertions(+), 4 deletions(-)
 create mode 100644 jadx-core/src/test/java/jadx/tests/integration/trycatch/TestTryCatchLastInsn.java
 create mode 100644 jadx-core/src/test/smali/trycatch/TestTryCatchLastInsn.smali

diff --git a/jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java b/jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java
index 91e59112..9fe3e199 100644
--- a/jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java
+++ b/jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java
@@ -29,6 +29,7 @@ import jadx.core.dex.info.MethodInfo;
 import jadx.core.dex.instructions.GotoNode;
 import jadx.core.dex.instructions.IfNode;
 import jadx.core.dex.instructions.InsnDecoder;
+import jadx.core.dex.instructions.InsnType;
 import jadx.core.dex.instructions.SwitchNode;
 import jadx.core.dex.instructions.args.ArgType;
 import jadx.core.dex.instructions.args.InsnArg;
@@ -332,7 +333,7 @@ public class MethodNode extends LineAttrNode implements ILoadable, ICodeNode {
 			InsnNode insn = null;
 			while (offset <= end && offset >= 0) {
 				insn = insnByOffset[offset];
-				if (insn != null) {
+				if (insn != null && insn.getType() != InsnType.NOP) {
 					if (tryBlockStarted) {
 						catchBlock.addInsn(insn);
 					} else if (insn.canThrowException()) {
@@ -343,9 +344,7 @@ public class MethodNode extends LineAttrNode implements ILoadable, ICodeNode {
 				}
 				offset = InsnDecoder.getNextInsnOffset(insnByOffset, offset);
 			}
-			if (insnByOffset[end] != null) {
-				insnByOffset[end].add(AFlag.TRY_LEAVE);
-			} else if (insn != null) {
+			if (tryBlockStarted && insn != null) {
 				insn.add(AFlag.TRY_LEAVE);
 			}
 		}
diff --git a/jadx-core/src/test/java/jadx/tests/api/SmaliTest.java b/jadx-core/src/test/java/jadx/tests/api/SmaliTest.java
index 2821e833..98e10a4c 100644
--- a/jadx-core/src/test/java/jadx/tests/api/SmaliTest.java
+++ b/jadx-core/src/test/java/jadx/tests/api/SmaliTest.java
@@ -31,6 +31,13 @@ public abstract class SmaliTest extends IntegrationTest {
 		return getClassNodeFromFile(outDex, clsName);
 	}
 
+	/**
+	 * Preferred method for one file smali test
+	 */
+	protected ClassNode getClassNodeFromSmali() {
+		return getClassNodeFromSmaliWithPkg(getTestPkg(), getTestName());
+	}
+
 	protected ClassNode getClassNodeFromSmali(String clsName) {
 		return getClassNodeFromSmali(clsName, clsName);
 	}
diff --git a/jadx-core/src/test/java/jadx/tests/integration/trycatch/TestTryCatchLastInsn.java b/jadx-core/src/test/java/jadx/tests/integration/trycatch/TestTryCatchLastInsn.java
new file mode 100644
index 00000000..d604d3b6
--- /dev/null
+++ b/jadx-core/src/test/java/jadx/tests/integration/trycatch/TestTryCatchLastInsn.java
@@ -0,0 +1,35 @@
+package jadx.tests.integration.trycatch;
+
+import org.junit.jupiter.api.Test;
+
+import jadx.core.dex.nodes.ClassNode;
+import jadx.tests.api.SmaliTest;
+
+import static jadx.tests.api.utils.JadxMatchers.containsOne;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+public class TestTryCatchLastInsn extends SmaliTest {
+
+	// @formatter:off
+	/*
+		public Exception test() {
+			? r1 = "result"; // String
+			try {
+				r1 = call(); // Exception
+			} catch(Exception e) {
+				System.out.println(r1); // String
+				r1 = e;
+			}
+			return r1;
+		}
+	*/
+	// @formatter:on
+
+	@Test
+	public void test() {
+		ClassNode cls = getClassNodeFromSmali();
+		String code = cls.getCode().toString();
+
+		assertThat(code, containsOne("return call();"));
+	}
+}
diff --git a/jadx-core/src/test/smali/trycatch/TestTryCatchLastInsn.smali b/jadx-core/src/test/smali/trycatch/TestTryCatchLastInsn.smali
new file mode 100644
index 00000000..e98f08aa
--- /dev/null
+++ b/jadx-core/src/test/smali/trycatch/TestTryCatchLastInsn.smali
@@ -0,0 +1,34 @@
+.class public Ltrycatch/TestTryCatchLastInsn;
+.super Ljava/lang/Object;
+.source "TestTryCatchLastInsn.java"
+
+.method public test()Ljava/lang/Exception;
+    .registers 6
+
+    .prologue
+    const-string v1, "result"
+
+    :try_start
+    invoke-direct {p0}, Ltrycatch/TestTryCatchLastInsn;->call()Ljava/lang/Exception;
+    move-result-object v1
+    :try_end
+    .catch Ljava/lang/Exception; {:try_start .. :try_end} :catch
+
+    :goto_return
+    return-object v1
+
+    :catch
+    move-exception v4
+    sget-object v3, Ljava/lang/System;->out:Ljava/io/PrintStream;
+    invoke-virtual {v3, v1}, Ljava/io/PrintStream;->println(Ljava/lang/String;)V
+    move-object v1, v4
+    goto :goto_return
+.end method
+
+
+.method private call()Ljava/lang/Exception;
+    .registers 2
+    new-instance v0, Ljava/lang/Exception;
+    invoke-direct {v0}, Ljava/lang/Exception;-><init>()V
+    return-object v0
+.end method
-- 
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