@Test
 public void calculateHelpPrefixWindowsSeparator() {
   assertEquals("test/one", markupToEclipseHelp.calculateHelpPrefix("test\\one"));
 }
 @Test
 public void calculateHelpPrefixWithHelpPrefix() {
   markupToEclipseHelp.helpPrefix = "help";
   assertEquals("help/test/one", markupToEclipseHelp.calculateHelpPrefix("test/one"));
 }
 @Test
 public void calculateHelpPrefix() {
   assertEquals("test/one", markupToEclipseHelp.calculateHelpPrefix("test/one"));
 }
 @Test
 public void calculateHelpPrefixRootWithHelpPrefix() {
   markupToEclipseHelp.helpPrefix = "help";
   assertEquals("help", markupToEclipseHelp.calculateHelpPrefix(""));
 }
 @Test
 public void calculateHelpPrefixRoot() {
   assertNull(markupToEclipseHelp.calculateHelpPrefix(""));
 }