getThemeConfig.js

module.exports = function getThemeConfig(grunt, prop) {
  "use strict";

  var happyplan = grunt.config.getRaw('happyplan')
    , theme = happyplan
    , finalValue = grunt.util.namespace.get(theme, grunt.config.getPropString(prop))
    , value
    , stupidityLimit = 20
    , stupidityChecker = 0

  while(theme.parent) {
    if (!happyplan.theme[theme.parent]) {
      grunt.fail.warn("Specified parent theme '" + theme.parent + "' doesn't exist")
    }
    theme = happyplan.theme[theme.parent]
    value = grunt.util.namespace.get(theme, grunt.config.getPropString(prop))
    if (finalValue instanceof Array) {
      if (value instanceof Array) {
        finalValue = value.concat(finalValue);
      }
      else {
        finalValue.unshift(value);
      }
    }
    else if (finalValue instanceof Object) {
      if (value instanceof Object) {
        for(i in value) {
          if(value.hasOwnProperty(i)) {
            theme[i] = custom[i]
          }
        }
        finalValue = value.concat(finalValue);
      }
      else {
        grunt.fail.warn("Can't append a simple typed value into an object, check your configuration to match parent one")
      }
    }
    else {
      if (value instanceof Array) {
        value.push(finalValue);
      }
      else {
        grunt.fail.warn("Can't append a simple typed value into an object or an array, check your configuration to match parent one")
      }
    }

    // prevent stupid infinite loop
    if (++stupidityChecker>stupidityLimit) {
      grunt.fail.warn("Your theme tree is deeper than " + stupidityLimit + ", stupidity limit reached.")
    }
  }

  return finalValue
}