Gammon Forum

The code for adding to the command history specifically disallows adding empty strings:

void CSendView::AddToCommandHistory (const CString & strCommand)
  {
CMUSHclientDoc* pDoc = GetDocument();
ASSERT_VALID(pDoc);

// do not record null commands, or ones identical to the previous one
// also do not record if the server has suppressed echoes

  if (!strCommand.IsEmpty () &&     // <------------------------- HERE
      strCommand != m_last_command &&
      !(pDoc->m_bNoEcho && !pDoc->m_bAlwaysRecordCommandHistory)) 
    {
    if (m_inputcount >= pDoc->m_nHistoryLines)
      {
      m_msgList.RemoveHead ();   // keep max of "m_nHistoryLines" previous commands
      m_HistoryFindInfo.m_nCurrentLine--;     // adjust for a "find again"
      if (m_HistoryFindInfo.m_nCurrentLine < 0)
        m_HistoryFindInfo.m_nCurrentLine = 0;
      }
    else
      m_inputcount++;
    m_msgList.AddTail (strCommand);  // <----- COMMAND ADDED HERE
    m_last_command = strCommand;
    }

  // history starts at bottom of list again - especially as we may have discarded lines
  m_HistoryPosition = NULL;
  m_iHistoryStatus = eAtBottom;

  } // end of  CSendView::AddToCommandHistory 

Both of you were incorrect that an empty string was added to the command window, which is why I couldn’t reproduce it. After running your tests (clicking the hyperlink) I immediately pressed Ctrl+H to see the command history, and there was no extra, blank, command there, which then mysteriously disappeared later. :)

What was actually happening was that when you click on the output window, the focus moves to that part of the screen. You will notice that when you click on the output window the cursor stops flashing in the command window, because it no longer has the focus.

Certain actions, like ordinary typing, are designed to first put the focus back into the command window, which is why you probably don’t usually notice this.

See here for example:

/* If AllTypingToCommandWindow is enabled we redirect character messages to 
 * the bottom view. */

void CMUSHView::OnChar(UINT nChar, UINT nRepCnt, UINT nFlags) 
{
  if (App.m_bAllTypingToCommandWindow) {
    OnKeysActivatecommandview();
    m_bottomview->SendMessage(WM_CHAR, nChar, nRepCnt | (nFlags << 16));
  } else
    CView::OnChar(nChar, nRepCnt, nFlags);
}

However the command window expects a special message (ID_KEYS_PREVCOMMAND, not WM_CHAR) in order to call the function which recalls the previous command, so that wasn’t acted on.

If you look carefully at your current version, when you press up-arrow after clicking on the hyperlink, the cursor starts flashing in the command window, so now pressing up-arrow recalls the previous command.

I’ve made a modification to force the focus back to the command window after clicking on a hyperlink (commit b9e52a1) which is available now from the pre-release page, see here.

This has been an interesting example of the X-Y Problem - both of you confidently reported that an extra entry was being inserted into the command window, something I couldn’t reproduce because I immediately pressed Ctrl+H to view the command window.

What the problem really was: After clicking on a hyperlink, pressing up-arrow to recall the previous command does not work. Or if you were really observant: After clicking on a hyperlink the focus does not return to the command window.