wro4j-extensions/src/main/java/ro/isdc/wro/extensions/processor/support/sass/RubySassEngine.java
public String process(final String content) {
    if (isEmpty(content)) {
      return StringUtils.EMPTY;
    }
    try {
      synchronized(this) {
        return engineInitializer.get().eval(buildUpdateScript(content)).toString();
      }
    } catch (final ScriptException e) {
      throw new WroRuntimeException(e.getMessage(), e);
    }
  }
public String process(final String content) {
    if (isEmpty(content)) {
      return StringUtils.EMPTY;
    }
    try {
      synchronized(this) {
        return engineInitializer.get().eval(buildUpdateScript(content)).toString();
      }
    } catch (final ScriptException e) {
      throw new WroRuntimeException(e.getMessage(), e);
    }
  }
Transforms a sass content into css using Sass ruby engine. This method is synchronized because the engine itself is
not thread-safe.

@param content
the Sass content to process.