keep comments on introduce variable (IDEA-136027)

java/java-impl/src/com/intellij/refactoring/introduceVariable/IntroduceVariableBase.java

@@ -58,6 +58,7 @@ import com.intellij.util.IncorrectOperationException;
 import com.intellij.util.Processor;
 import com.intellij.util.containers.ContainerUtil;
 import com.intellij.util.containers.MultiMap;
+import com.siyeh.ig.psiutils.CommentTracker;
 import org.jetbrains.annotations.NonNls;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -924,7 +925,9 @@ public abstract class IntroduceVariableBase extends IntroduceHandlerBase {
               if (lastChild instanceof PsiComment) { // keep trailing comment
                 declaration.addBefore(lastChild, null);
               }
-              statement.delete();
+              CommentTracker commentTracker = new CommentTracker();
+              commentTracker.markUnchanged(initializer);
+              commentTracker.deleteAndRestoreComments(statement);
               if (editor != null) {
                 LogicalPosition pos = new LogicalPosition(line, col);
                 editor.getCaretModel().moveToLogicalPosition(pos);

java/java-tests/testData/refactoring/introduceVariable/KeepComments.after.java

+import java.util.Arrays;
+import java.util.List;
+
+class Main {
+
+
+    private static void foo(String... src){
+        String m = Arrays.asList(src)
+                //c-2
+                .toArray()//c-1
+                .toString();//c1
+//c2
+    }
+}
\ No newline at end of file

java/java-tests/testData/refactoring/introduceVariable/KeepComments.java

+import java.util.Arrays;
+import java.util.List;
+
+class Main {
+
+
+    private static void foo(String... src){
+        <selection>Arrays.asList(src)
+                //c-2
+                .toArray()//c-1
+                .toString()</selection>
+        //c1
+        //c2
+        ;
+    }
+}
\ No newline at end of file

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

@@ -539,6 +539,10 @@ public class IntroduceVariableTest extends LightCodeInsightTestCase {
     doTest(new MockIntroduceVariableHandler("m", false, false, false, "A<? extends A<? extends java.lang.Object>>"));
   }
 
+  public void testKeepComments() {
+    doTest(new MockIntroduceVariableHandler("m", false, false, false, CommonClassNames.JAVA_LANG_STRING));
+  }
+
   public void testDenotableType2() {
     doTest(new MockIntroduceVariableHandler("m", false, false, false, "I<? extends I<?>>"));
   }