Since this is one of the top hits on google ill provide the ruby solution if you cant use the http://username:password@url.

you can use system input but doing it on windows and on mac are different. Here is the solution on a mac:

You would have to detect if the test is running on windows or mac first and then do the corresponding.

  t1=Thread.new{
    @browser.get 'url';

  }
  t2=Thread.new{
    sleep (10)
    #replace these lines with the windows corresponding if on windows.
    %x(osascript -e 'tell application "System Events" to keystroke "username"')
    %x(osascript -e 'tell application "System Events" to keystroke tab')
    %x(osascript -e 'tell application "System Events" to keystroke "password"')
    %x(osascript -e 'tell application "System Events" to keystroke return')

  }
  t1.join()
  t2.join()

Since this is one of the top hits on google ill provide the ruby solution if you cant use the http://username:password@url.

you can use system input but doing it on windows and on mac are different. Here is the solution on a mac:

You would have to detect if the test is running on windows or mac first and then do the corresponding.

  t1=Thread.new{
    @browser.get 'url';

  }
  t2=Thread.new{
    sleep (10)
    #replace these lines with the windows corresponding if on windows.
    %x(osascript -e 'tell application "System Events" to keystroke "username"')
    %x(osascript -e 'tell application "System Events" to keystroke tab')
    %x(osascript -e 'tell application "System Events" to keystroke "password"')
    %x(osascript -e 'tell application "System Events" to keystroke return')

  }
  t1.join()
  t2.join()

Here is the windows solution:

t1=Thread.new{
    @browser.get 'url'  

}
t2=Thread.new{
    sleep (5)
    wsh = WIN32OLE.new('Wscript.Shell')
    wsh.AppActivate('browser') #fx. firefox
    wsh.SendKeys('username{TAB}password{ENTER}')
}
t1.join()
t2.join()