docs: private static String reduceVariant(final String variant){
  		if (isEmpty(variant))
  			throw new AssertionError("Shouldn't happen, can't reduce non existent variant");
  		
  		int indexOfUnderscore = variant.lastIndexOf('_');
  		if (indexOfUnderscore==-1)
  			return "";
  		return variant.substring(0, indexOfUnderscore);
  	}