inherit unrelated abstract/default through hierarchy (IDEA-146070)

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/interfaceMethods/MultipleDefaultsAndAbstractsSomeOfWhichOverridesEachOther.java

@@ -0,0 +1,55 @@
+class Test1 {
+  interface A {
+    default void foo() { }
+  }
+
+  abstract class B {
+    public abstract void foo();
+  }
+
+  abstract class C extends B implements A { }
+}
+
+class Test2 {
+  interface A {
+    default void foo() { }
+  }
+
+  interface B extends A {}
+
+  interface C extends A {
+    default void foo() {}
+  }
+  abstract  class D implements  C, B { }
+}
+
+
+class Test3 {
+
+  interface A {
+    void accept();
+  }
+  interface B extends A {}
+
+  interface C extends A {
+    default void accept(){}
+  }
+
+  class D implements B, C {}
+}
+
+class Test4 {
+
+  interface A {
+    default void accept(){}
+  }
+  interface B extends A {}
+
+  interface C extends A {
+    void accept();
+  }
+
+  <error descr="Class 'D' must either be declared abstract or implement abstract method 'accept()' in 'C'">class <error descr="Class 'D' must either be declared abstract or implement abstract method 'accept()' in 'C'">D</error> implements B, C</error> {}
+  abstract class E implements B, C {}
+}
+

java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/Interface8MethodsHighlightingTest.java

@@ -89,6 +89,10 @@ public class Interface8MethodsHighlightingTest extends LightCodeInsightFixtureTe
     doTest();
   }
 
+  public void testMultipleDefaultsAndAbstractsSomeOfWhichOverridesEachOther() throws Exception {
+    doTest();
+  }
+
   private void doTest() {
     doTest(false, false);
   }