inline: ensure to insert valid specification (IDEA-161992)

java/java-impl/src/com/intellij/refactoring/util/InlineUtil.java

@@ -27,6 +27,7 @@ import com.intellij.psi.search.LocalSearchScope;
 import com.intellij.psi.search.searches.ReferencesSearch;
 import com.intellij.psi.tree.IElementType;
 import com.intellij.psi.util.PsiTreeUtil;
+import com.intellij.psi.util.PsiTypesUtil;
 import com.intellij.psi.util.RedundantCastUtil;
 import com.intellij.refactoring.RefactoringBundle;
 import com.intellij.util.IncorrectOperationException;
@@ -127,7 +128,7 @@ public class InlineUtil {
             if (substituted == null) break;
             copy.getTypeArgumentList().add(elementFactory.createTypeElement(substituted));
           }
-          if (varType.equals(copy.getType())) {
+          if (varType.equals(copy.getType()) && copy.resolveMethodGenerics().isValidResult()) {
             ((PsiCallExpression)expr).getTypeArgumentList().replace(copy.getTypeArgumentList());
             return (PsiMethod)resolved;
           }

java/java-tests/testData/refactoring/inlineLocal/AvoidTypeSpecificationWhenPossibleToAvoid.java

@@ -0,0 +1,12 @@
+import java.util.Collection;
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+class Main {
+  public Collection<? extends Number> get() {
+    List<Number> lis<caret>t = IntStream.range(0, 100).boxed().collect(Collectors.toList());
+    return list;
+  }
+
+}

java/java-tests/testData/refactoring/inlineLocal/AvoidTypeSpecificationWhenPossibleToAvoid.java.after

@@ -0,0 +1,11 @@
+import java.util.Collection;
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+class Main {
+  public Collection<? extends Number> get() {
+      return IntStream.range(0, 100).boxed().collect(Collectors.toList());
+  }
+
+}

java/java-tests/testSrc/com/intellij/refactoring/inline/InlineLocalTest.java

@@ -292,6 +292,10 @@ public class InlineLocalTest extends LightCodeInsightTestCase {
                  "Variable 'hello' is accessed for writing");
   }
 
+  public void testAvoidTypeSpecificationWhenPossibleToAvoid() throws Exception {
+    doTest(false);
+  }
+
   private void doTest(final boolean inlineDef, String conflictMessage) throws Exception {
     try {
       doTest(inlineDef);