Support handle sudo password

lib/serverspec.rb

@@ -17,6 +17,7 @@
   c.include(Serverspec::Helper::Debian,  :os => :debian)
   c.include(Serverspec::Helper::Gentoo,  :os => :gentoo)
   c.include(Serverspec::Helper::Solaris, :os => :solaris)
-  c.add_setting :host, :default => nil
-  c.add_setting :ssh,  :default => nil
+  c.add_setting :host,          :default => nil
+  c.add_setting :ssh,           :default => nil
+  c.add_setting :sudo_password, :default => nil
 end

lib/serverspec/backend/ssh.rb

@@ -22,15 +22,22 @@ def ssh_exec!(command)
           end
           channel.exec("#{command}") do |ch, success|
             abort "FAILED: couldn't execute command (ssh.channel.exec)" if !success
-            channel.on_data do |ch,data|
-              stdout_data += data
+            channel.on_data do |ch, data|
+              if data =~ /^\[sudo\] password for/
+                channel.send_data "#{RSpec.configuration.sudo_password}\n"
+                channel.on_data do |ch, data|
+                  stdout_data += data
+                end
+              else
+                stdout_data += data
+              end
             end
 
-            channel.on_extended_data do |ch,type,data|
+            channel.on_extended_data do |ch, type, data|
               stderr_data += data
             end
 
-            channel.on_request("exit-status") do |ch,data|
+            channel.on_request("exit-status") do |ch, data|
               exit_code = data.read_long
             end