title: Sencha build failed compass process exited with non-zero code 1
body: <p>I am trying to build my Sencha app at windows OS but getting this error.
  I am trying to use sencha command - sencha app build package, but build is failed.
  I already installed ant and compass</p>
  
  <pre><code>C:\xampp\htdocs\WhatsUnderMe&gt;sencha app build package
  Sencha Cmd v3.1.0.256
  [INF]
  [INF] init-plugin:
  [INF]
  [INF] init-plugin:
  [INF] Invoking plugin (C:\xampp\htdocs\WhatsUnderMe\.sencha\app\plugin.xml) - supported targets: -before-app-build
  [INF]
  [INF] -before-app-build:
  [INF] Invoking plugin (C:\xampp\htdocs\WhatsUnderMe\.sencha\app\plugin.xml) - supported targets: app-build
  [INF]
  [INF] cmd-root-plugin.init-properties:
  [INF]
  [INF] init-properties:
  [INF]
  [INF] init-sencha-command:
  [INF]
  [INF] init:
  [INF]
  [INF] -before-app-build:
  [INF]
  [INF] app-build-impl:
  [INF]
  [INF] package:
  [INF]
  [INF] -before-init-local:
  [INF]
  [INF] -init-local:
  [INF]
  [INF] -after-init-local:
  [INF]
  [INF] init-local:
  [INF]
  [INF] find-cmd:
  [INF]
  [INF] -before-init:
  [INF]
  [INF] -init:
  [INF] Initializing Sencha Cmd ant environment
  [INF] Adding antlib taskdef for com/sencha/command/compass/ant/antlib.xml
  [INF]
  [INF] -after-init:
  [INF]
  [INF] init:
  [INF]
  [INF] -before-build:
  [INF]
  [INF] sass:
  [INF]
  [INF] -before-sass:
  [INF]
  [INF] -sass:
  [INF] executing compass using system installed ruby runtime
  NoMethodError on line ["23"] of C: undefined method `empty?' for nil:NilClass
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/sass-3.1.7/lib/sass/engine.rb:293:in `_render'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/sass-3.1.7/lib/sass/engine.rb:240:in `render'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/compiler.rb:140:in `block (2 leve
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/compiler.rb:126:in `timed'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/compiler.rb:139:in `block in comp
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/logger.rb:45:in `red'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/compiler.rb:138:in `compile'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/compiler.rb:118:in `compile_if_re
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/compiler.rb:103:in `block (2 leve
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/compiler.rb:101:in `each'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/compiler.rb:101:in `block in run'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/compiler.rb:126:in `timed'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/compiler.rb:100:in `run'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/commands/update_project.rb:45:in
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/commands/base.rb:18:in `execute'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/commands/project_base.rb:19:in `e
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/exec/sub_command_ui.rb:43:in `per
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/lib/compass/exec/sub_command_ui.rb:15:in `run
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/bin/compass:30:in `block in &lt;top (required)&gt;'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/bin/compass:44:in `call'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/gems/compass-0.12.2/bin/compass:44:in `&lt;top (required)&gt;'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/bin/compass:23:in `load'
    C:/Users/Ido Tsuk/bin/Sencha/Cmd/3.1.0.256/extensions/sencha-compass/gems/bin/compass:23:in `&lt;main&gt;'
  [ERR]
  [ERR] BUILD FAILED
  [ERR] com.sencha.exceptions.ExProcess: compass process exited with non-zero code : 1
  [ERR]
  [ERR] Total time: 0 seconds
  [ERR]
  [ERR] BUILD FAILED
  [ERR] com.sencha.exceptions.BasicException: The following error occurred while executing this line:
  [ERR] C:\xampp\htdocs\WhatsUnderMe\.sencha\app\build-impl.xml:223: com.sencha.exceptions.ExProcess: compass process exited with non-zero code
  [ERR]
  [ERR] Total time: 1 second
  [ERR] com.sencha.exceptions.BasicException: The following error occurred while executing this line:
  C:\xampp\htdocs\WhatsUnderMe\.sencha\app\build-impl.xml:223: com.sencha.exceptions.ExProcess: compass process exited with non-zero code : 1
  </code></pre>
  
  <p>What can i do to solve it?</p>