Fix NPE when decompiling constructor #654

src/org/jetbrains/java/decompiler/modules/decompiler/exps/ExprUtil.java

@@ -1,12 +1,11 @@
-/*
- * Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
- */
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package org.jetbrains.java.decompiler.modules.decompiler.exps;
 
 import org.jetbrains.java.decompiler.code.CodeConstants;
 import org.jetbrains.java.decompiler.main.ClassesProcessor.ClassNode;
 import org.jetbrains.java.decompiler.main.DecompilerContext;
 import org.jetbrains.java.decompiler.main.rels.ClassWrapper;
+import org.jetbrains.java.decompiler.main.rels.MethodWrapper;
 import org.jetbrains.java.decompiler.modules.decompiler.vars.VarVersionPair;
 
 import java.util.ArrayList;
@@ -25,7 +24,11 @@ public class ExprUtil {
     ClassWrapper wrapper = node.getWrapper();
     if (wrapper != null) {
       // own class
-      mask = wrapper.getMethodWrapper(CodeConstants.INIT_NAME, descriptor).synthParameters;
+      MethodWrapper methodWrapper = wrapper.getMethodWrapper(CodeConstants.INIT_NAME, descriptor);
+      if (methodWrapper == null) {
+        return null;
+      }
+      mask = methodWrapper.synthParameters;
     }
     else if (parameters > 0 && node.type == ClassNode.CLASS_MEMBER && (node.access & CodeConstants.ACC_STATIC) == 0) {
       // non-static member class

test/org/jetbrains/java/decompiler/SingleClassesTest.java

@@ -104,6 +104,9 @@ public class SingleClassesTest {
   @Test public void testPop2TwoIntPop2() { doTest("pkg/TestPop2TwoIntPop2"); }
   @Test public void testPop2TwoIntTwoPop() { doTest("pkg/TestPop2TwoIntTwoPop"); }
   @Test public void testSuperInner() { doTest("pkg/TestSuperInner", "pkg/TestSuperInnerBase"); }
+  @Test public void testMissingConstructorCallGood() { doTest("pkg/TestMissingConstructorCallGood"); }
+  @Test public void testMissingConstructorCallBad() { doTest("pkg/TestMissingConstructorCallBad"); }
+
 
   // TODO: fix all below
   //@Test public void testPackageInfo() { doTest("pkg/package-info"); }

testData/results/TestMissingConstructorCallBad.dec

@@ -0,0 +1,50 @@
+package pkg;
+
+public class TestMissingConstructorCallBad {
+   private TestMissingConstructorCallBad() {
+      System.out.println("Nobody will see what we do here!");// 14 15 16
+      this((Object)null);// 19 20
+   }// 21
+
+   public static void main(String... var0) {
+      try {
+         new TestMissingConstructorCallBad();
+      } catch (Throwable var2) {// 37
+         ;
+      }
+
+   }// 39
+}
+
+class 'pkg/TestMissingConstructorCallBad' {
+   method '<init> ()V' {
+      0      4
+      3      4
+      5      4
+      9      5
+      a      5
+      d      6
+   }
+
+   method 'main ([Ljava/lang/String;)V' {
+      b      11
+      c      15
+   }
+}
+
+Lines mapping:
+14 <-> 5
+15 <-> 5
+16 <-> 5
+19 <-> 6
+20 <-> 6
+21 <-> 7
+37 <-> 12
+39 <-> 16
+Not mapped:
+18
+28
+29
+30
+31
+33

testData/results/TestMissingConstructorCallGood.dec

@@ -0,0 +1,60 @@
+package pkg;
+
+public class TestMissingConstructorCallGood {
+   private TestMissingConstructorCallGood(Object var1) {
+   }// 16
+
+   private TestMissingConstructorCallGood() {
+      System.out.println("Nobody will see what we do here!");// 22 23 24
+      this((Object)null);// 27 28
+   }// 29
+
+   public static void main(String... var0) {
+      try {
+         new TestMissingConstructorCallGood();
+      } catch (Throwable var2) {// 45
+         ;
+      }
+
+   }// 47
+}
+
+class 'pkg/TestMissingConstructorCallGood' {
+   method '<init> (Ljava/lang/Object;)V' {
+      4      4
+   }
+
+   method '<init> ()V' {
+      0      7
+      3      7
+      5      7
+      9      8
+      a      8
+      d      9
+   }
+
+   method 'main ([Ljava/lang/String;)V' {
+      b      14
+      c      18
+   }
+}
+
+Lines mapping:
+16 <-> 5
+22 <-> 8
+23 <-> 8
+24 <-> 8
+27 <-> 9
+28 <-> 9
+29 <-> 10
+45 <-> 15
+47 <-> 19
+Not mapped:
+14
+15
+26
+36
+37
+38
+39
+41

testData/src/pkg/TestMissingConstructorCallBad.jasm

@@ -0,0 +1,42 @@
+/**
+ * This code can be assembled with <a href="https://wiki.openjdk.java.net/display/CodeTools/asmtools">asmtools</a>
+ * using <code>asmtools jasm -g *.jasm</code> command line.
+ */
+package  pkg;
+
+super public class TestMissingConstructorCallBad
+	version 52:0
+{
+
+private Method "<init>":"()V"
+	stack 2 locals 1
+{
+		getstatic	Field java/lang/System.out:"Ljava/io/PrintStream;";
+		ldc	String "Nobody will see what we do here!";
+		invokevirtual	Method java/io/PrintStream.println:"(Ljava/lang/String;)V";
+
+        aload_0;
+		aconst_null;
+		invokespecial	Method "<init>":"(Ljava/lang/Object;)V";
+		return;
+}
+
+public static varargs Method main:"([Ljava/lang/String;)V"
+	stack 2 locals 2
+{
+		try t0;
+		new	class TestMissingConstructorCallBad;
+		dup;
+		invokespecial	Method "<init>":"()V";
+		pop;
+		endtry t0;
+		goto	L12;
+		catch t0 java/lang/Throwable;
+		stack_frame_type stack1;
+		stack_map class java/lang/Throwable;
+		astore_1;
+	L12:	stack_frame_type same;
+		return;
+}
+
+} // end Class TestMissingConstructorCallBad

testData/src/pkg/TestMissingConstructorCallGood.jasm

@@ -0,0 +1,50 @@
+/**
+ * This code can be assembled with <a href="https://wiki.openjdk.java.net/display/CodeTools/asmtools">asmtools</a>
+ * using <code>asmtools jasm -g *.jasm</code> command line.
+ */
+package  pkg;
+
+super public class TestMissingConstructorCallGood
+	version 52:0
+{
+
+private Method "<init>":"(Ljava/lang/Object;)V"
+	stack 1 locals 2
+{
+		aload_0;
+		invokespecial	Method java/lang/Object."<init>":"()V";
+		return;
+}
+
+private Method "<init>":"()V"
+	stack 2 locals 1
+{
+		getstatic	Field java/lang/System.out:"Ljava/io/PrintStream;";
+		ldc	String "Nobody will see what we do here!";
+		invokevirtual	Method java/io/PrintStream.println:"(Ljava/lang/String;)V";
+
+        aload_0;
+		aconst_null;
+		invokespecial	Method "<init>":"(Ljava/lang/Object;)V";
+		return;
+}
+
+public static varargs Method main:"([Ljava/lang/String;)V"
+	stack 2 locals 2
+{
+		try t0;
+		new	class TestMissingConstructorCallGood;
+		dup;
+		invokespecial	Method "<init>":"()V";
+		pop;
+		endtry t0;
+		goto	L12;
+		catch t0 java/lang/Throwable;
+		stack_frame_type stack1;
+		stack_map class java/lang/Throwable;
+		astore_1;
+	L12:	stack_frame_type same;
+		return;
+}
+
+} // end Class TestMissingConstructorCallGood