EA-41231 (omit synthetic inner class constructor parameter)

src/org/jetbrains/java/decompiler/main/ClassWriter.java

@@ -250,7 +250,7 @@ public class ClassWriter {
       for (ClassNode inner : node.nested) {
         if (inner.type == ClassNode.CLASS_MEMBER) {
           StructClass innerCl = inner.classStruct;
-          boolean isSynthetic = (inner.access & CodeConstants.ACC_SYNTHETIC) != 0 || innerCl.isSynthetic();
+          boolean isSynthetic = (inner.access & CodeConstants.ACC_SYNTHETIC) != 0 || innerCl.isSynthetic() || inner.namelessConstructorStub;
           boolean hide = isSynthetic && DecompilerContext.getOption(IFernflowerPreferences.REMOVE_SYNTHETIC) ||
                          wrapper.getHiddenMembers().contains(innerCl.qualifiedName);
           if (hide) continue;

src/org/jetbrains/java/decompiler/main/ClassesProcessor.java

@@ -359,6 +359,7 @@ public class ClassesProcessor {
     public Set<String> enclosingClasses = new HashSet<String>();
     public ClassNode parent;
     public LambdaInformation lambdaInformation;
+    public boolean namelessConstructorStub = false;
 
     public ClassNode(String content_class_name,
                      String content_method_name,

src/org/jetbrains/java/decompiler/main/rels/NestedClassProcessor.java

@@ -79,6 +79,7 @@ public class NestedClassProcessor {
           DecompilerContext.getLogger().writeMessage(message, IFernflowerLogger.Severity.WARN);
           child.simpleName = "NamelessClass_" + (++nameless);
         }
+        child.namelessConstructorStub = !cl.hasModifier(CodeConstants.ACC_STATIC) && cl.getMethods().size() + cl.getFields().size() == 0;
       }
     }
 

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

@@ -311,20 +311,31 @@ public class NewExprent extends Exprent {
           if (!enumconst || start < lstParameters.size()) {
             buf.append("(");
 
-            boolean firstpar = true;
+            boolean firstParam = true;
             for (int i = start; i < lstParameters.size(); i++) {
               if (sigFields == null || sigFields.get(i) == null) {
-                if (!firstpar) {
+                Exprent expr = lstParameters.get(i);
+                VarType leftType = constructor.getDescriptor().params[i];
+
+                if (i == lstParameters.size() - 1 && expr.getExprType() == VarType.VARTYPE_NULL) {
+                  ClassNode node = DecompilerContext.getClassProcessor().getMapRootClasses().get(leftType.value);
+                  if (node != null && node.namelessConstructorStub) {
+                    break;  // skip last parameter of synthetic constructor call
+                  }
+                }
+
+                if (!firstParam) {
                   buf.append(", ");
                 }
 
                 TextBuffer buff = new TextBuffer();
-                ExprProcessor.getCastedExprent(lstParameters.get(i), constructor.getDescriptor().params[i], buff, indent, true, tracer);
-
+                ExprProcessor.getCastedExprent(expr, leftType, buff, indent, true, tracer);
                 buf.append(buff);
-                firstpar = false;
+
+                firstParam = false;
               }
             }
+
             buf.append(")");
           }
         }

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

@@ -34,4 +34,6 @@ public class SingleClassesTest extends SingleClassesTestBase {
   @Test public void testEnum() { doTest("pkg/TestEnum"); }
   @Test public void testDebugSymbols() { doTest("pkg/TestDebugSymbols"); }
   @Test public void testInvalidMethodSignature() { doTest("InvalidMethodSignature"); }
+  @Test public void testInnerClassConstructor() { doTest("pkg/TestInnerClassConstructor"); }
+  @Test public void testInnerClassConstructor11() { doTest("v11/TestInnerClassConstructor"); }
 }

testData/results/TestInnerClassConstructor.dec

@@ -0,0 +1,17 @@
+package pkg;
+
+class TestInnerClassConstructor {
+   void m() {
+      new TestInnerClassConstructor.Inner("text");
+   }
+
+   void n(String var1) {
+      System.out.println("n(): " + var1);
+   }
+
+   final class Inner {
+      private Inner(String var2) {
+         TestInnerClassConstructor.this.n(var2);
+      }
+   }
+}

testData/src/pkg/TestInnerClassConstructor.java

@@ -0,0 +1,17 @@
+package pkg;
+
+class TestInnerClassConstructor {
+  void m() {
+    new Inner("text");
+  }
+
+  void n(String s) {
+    System.out.println("n(): " + s);
+  }
+
+  final class Inner {
+    private Inner(String s) {
+      n(s);
+    }
+  }
+}