push down: search for method in inheritor by super method signature (IDEA-86806)

java/java-impl/src/com/intellij/refactoring/memberPushDown/PushDownProcessor.java

@@ -30,6 +30,7 @@ import com.intellij.psi.codeStyle.JavaCodeStyleManager;
 import com.intellij.psi.javadoc.PsiDocComment;
 import com.intellij.psi.search.searches.ClassInheritorsSearch;
 import com.intellij.psi.search.searches.ReferencesSearch;
+import com.intellij.psi.util.MethodSignatureUtil;
 import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.psi.util.PsiUtil;
 import com.intellij.psi.util.TypeConversionUtil;
@@ -356,7 +357,8 @@ public class PushDownProcessor extends BaseRefactoringProcessor {
       }
       else if (member instanceof PsiMethod) {
         PsiMethod method = (PsiMethod)member;
-        final PsiMethod methodBySignature = targetClass.findMethodBySignature(method, false);
+        final PsiMethod methodBySignature =
+          MethodSignatureUtil.findMethodBySuperSignature(targetClass, method.getSignature(substitutor), false);
         if (methodBySignature == null) {
           final boolean wasInterface = myClass.isInterface();
           newMember = (PsiMethod)targetClass.add(method);

java/java-tests/testData/refactoring/pushDown/OverridingMethodWithSubst.java

@@ -0,0 +1,13 @@
+abstract class BaseTask<T, S extends BaseTask<T, S>> {
+  public abstract S make<caret>Task(int depth, ParallelStream<T> coll);
+}
+
+
+class ForEachTask<T> extends BaseTask<T, ForEachTask<T>> {
+  public ForEachTask<T> makeTask(int depth, ParallelStream<T> coll) {
+    return new ForEachTask<T>();
+  }
+}
+
+class ParallelStream<T> {
+}

java/java-tests/testData/refactoring/pushDown/OverridingMethodWithSubst.java.after

@@ -0,0 +1,12 @@
+abstract class BaseTask<T, S extends BaseTask<T, S>> {
+}
+
+
+class ForEachTask<T> extends BaseTask<T, ForEachTask<T>> {
+  public ForEachTask<T> makeTask(int depth, ParallelStream<T> coll) {
+    return new ForEachTask<T>();
+  }
+}
+
+class ParallelStream<T> {
+}

java/java-tests/testSrc/com/intellij/refactoring/PushDownTest.java

@@ -115,6 +115,10 @@ public class PushDownTest extends LightRefactoringTestCase {
     doTest();
   }
 
+  public void testOverridingMethodWithSubst() throws Exception {
+    doTest();
+  }
+
   public void testSameClassInterface() throws Exception {
     final String filePath = "/refactoring/pushDown/" + getTestName(false) + ".java";
     configureByFile(filePath);