place missing comma(s) when caret is put between completion hints 'manually' (IDEA-178659)

java/java-tests/testSrc/com/intellij/java/codeInsight/completion/CompletionHintsTest.java

@@ -1369,6 +1369,17 @@ public class CompletionHintsTest extends AbstractParameterInfoTestCase {
                           "}");
   }
 
+  public void testCaretMovementOverVirtualComma() throws Exception {
+    enableVirtualComma();
+
+    configureJava("class C { void m() { System.getPro<caret> } }");
+    complete("getProperty(String key, String def)");
+    checkResultWithInlays("class C { void m() { System.getProperty(<HINT text=\"key:\"/><caret><Hint text=\",def:\"/>) } }");
+
+    right();
+    checkResultWithInlays("class C { void m() { System.getProperty(<Hint text=\"key:\"/>, <HINT text=\"def:\"/><caret>) } }");
+  }
+
   private void checkResultWithInlays(String text) {
     myFixture.checkResultWithInlays(text);
   }