Getting a syntax error in Sessions#controller

I am trying to use the same code that I used in rails 3 for sessions.

 def create
   user = User.find_by_name(params[:name])

   if user && user.authenticate(params[:password])
     session[:user_id] = user.id    #stores the id in the session
     redirect_to user       #displays the user/show view
   else             
     flash.now[:error] = "Invalid name/password combination."
     render 'new'                   
   end
 end

I have adjusted it to

def create
  user = User.find_by_username(params[:username])

  if user && user.authenticate(params[:password])
    session[:user_id] = user.id #stores the id in the session 
    redirect_to user #displays the user/show view
  else              
    flash.now[:error] = "Invalid name/password combination."
    render 'new' #shows the signin page again 
  end
end

But I am now getting the error:

"SyntaxError in SessionsController#new" 
 /sessions_controller.rb:5: syntax error, unexpected tIDENTIFIER, expecting keyword_then or ';' or '\n' ...te(params[:password]) session[:user_id] = user.id

I'm sure it is to do with the fact I am using rails 4 now and not 3 and there is some syntax that is not compatible with 4, but I can't seem to work it out.