simplify ? extends Object (IDEA-91631; IDEA-91144)

java/java-psi-api/src/com/intellij/psi/GenericsUtil.java

@@ -258,6 +258,7 @@ public class GenericsUtil {
             if (((PsiWildcardType)acceptedBound).isExtends() != wildcardType.isExtends()) return PsiWildcardType.createUnbounded(manager);
             return acceptedBound;
           }
+          if (wildcardType.isExtends() && acceptedBound.equalsToText(CommonClassNames.JAVA_LANG_OBJECT)) return PsiWildcardType.createUnbounded(manager);
           if (acceptedBound.equals(bound)) return wildcardType;
           return wildcardType.isExtends()
                  ? PsiWildcardType.createExtends(manager, acceptedBound)

java/java-tests/testData/codeInsight/overrideImplement/afterSimplifyObjectWildcard.java

@@ -0,0 +1,12 @@
+interface Generic<T> {
+  SomeGeneric<? extends T> foo();
+}
+
+class II implements Generic<Object> {
+    public SomeGeneric<?> foo() {
+        <selection>return null;  //To change body of implemented methods use File | Settings | File Templates.</selection>
+    }
+}
+
+class SomeGeneric<P> {
+}

java/java-tests/testData/codeInsight/overrideImplement/beforeSimplifyObjectWildcard.java

@@ -0,0 +1,10 @@
+interface Generic<T> {
+  SomeGeneric<? extends T> foo();
+}
+
+class II implements Generic<Object> {
+  <caret>
+}
+
+class SomeGeneric<P> {
+}

java/java-tests/testData/refactoring/introduceParameter/afterSimplifiedResultedType.java

@@ -0,0 +1,24 @@
+import java.util.*;
+public class IntroduceParameterProducesWarning {
+    private final List<Generic<?>> elements;
+
+    public IntroduceParameterProducesWarning(final ArrayList<Generic<?>> anObject) {
+        elements = anObject;
+    }
+
+    public static <E> ArrayList<E> newArrayList(E... elements) {
+        ArrayList<E> list = new ArrayList<E>();
+        Collections.addAll(list, elements);
+        return list;
+    }
+
+    private static interface Generic<T>{
+
+    }
+
+    private static class SomeGeneric implements Generic<String> {
+    }
+
+    private static class SomeOtherGeneric implements Generic<Object> {
+    }
+}

java/java-tests/testData/refactoring/introduceParameter/beforeSimplifiedResultedType.java

@@ -0,0 +1,24 @@
+import java.util.*;
+public class IntroduceParameterProducesWarning {
+    private final List<Generic<?>> elements;
+
+    public IntroduceParameterProducesWarning() {
+        elements = <selection>newArrayList(new SomeGeneric(), new SomeOtherGeneric())</selection>;
+    }
+
+    public static <E> ArrayList<E> newArrayList(E... elements) {
+        ArrayList<E> list = new ArrayList<E>();
+        Collections.addAll(list, elements);
+        return list;
+    }
+
+    private static interface Generic<T>{
+
+    }
+
+    private static class SomeGeneric implements Generic<String> {
+    }
+
+    private static class SomeOtherGeneric implements Generic<Object> {
+    }
+}

java/java-tests/testSrc/com/intellij/codeInsight/OverrideImplementTest.java

@@ -60,6 +60,7 @@ public class OverrideImplementTest extends LightCodeInsightTestCase {
   public void testSubstituteBoundInMethodTypeParam() { doTest(false); }
   public void testClone() { doTest(false); }
   public void testOnTheLineWithExistingExpression() { doTest(false); }
+  public void testSimplifyObjectWildcard() { doTest(false); }
 
   public void testImplementExtensionMethods() { doTest8(false, true); }
   public void testDoNotImplementExtensionMethods() { doTest8(false, true); }

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

@@ -313,6 +313,10 @@ public class IntroduceParameterTest extends LightRefactoringTestCase  {
     doTest(IntroduceParameterRefactoring.REPLACE_FIELDS_WITH_GETTERS_ALL, true, false, true, false);
   }
 
+  public void testSimplifiedResultedType() throws Exception {
+    doTest(IntroduceParameterRefactoring.REPLACE_FIELDS_WITH_GETTERS_ALL, true, false, true, false);
+  }
+
   private void doTestThroughHandler() throws Exception {
     configureByFile("/refactoring/introduceParameter/before" + getTestName(false) + ".java");
     boolean enabled = true;