Fix super qualifier for default interfaces #855

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

@@ -247,7 +247,9 @@ public class InvocationExprent extends Exprent {
 
           if (invocationTyp == INVOKE_SPECIAL) {
             if (!classname.equals(this_classname)) { // TODO: direct comparison to the super class?
-              super_qualifier = this_classname;
+              StructClass cl = DecompilerContext.getStructContext().getClass(classname);
+              boolean isInterface = cl != null && (cl.getAccessFlags() & CodeConstants.ACC_INTERFACE) != 0;
+              super_qualifier = !isInterface ? this_classname : classname;
             }
           }
         }

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

@@ -110,7 +110,7 @@ public class SingleClassesTest {
   @Test public void testEmptyBlocks() { doTest("pkg/TestEmptyBlocks"); }
   @Test public void testPrivateEmptyConstructor() { doTest("pkg/TestPrivateEmptyConstructor"); }
   @Test public void testSynchronizedUnprotected() { doTest("pkg/TestSynchronizedUnprotected"); }
-
+  @Test public void testInterfaceSuper() { doTest("pkg/TestInterfaceSuper"); }
 
   // TODO: fix all below
   //@Test public void testPackageInfo() { doTest("pkg/package-info"); }
@@ -118,7 +118,6 @@ public class SingleClassesTest {
   //@Test public void testUnionType() { doTest("pkg/TestUnionType"); }
   //@Test public void testInnerClassConstructor2() { doTest("pkg/TestInner2"); }
   //@Test public void testInUse() { doTest("pkg/TestInUse"); }
-  //@Test public void testInterfaceSuper() { doTest("pkg/TestInterfaceSuper"); }
 
   @Test public void testGroovyClass() { doTest("pkg/TestGroovyClass"); }
   @Test public void testGroovyTrait() { doTest("pkg/TestGroovyTrait"); }