Function flatten

code/styling/public/app.js:19853–19880

(chunks, executionContext)

};

var flatten = function flatten(chunks, executionContext) {
  return chunks.reduce(function (ruleSet, chunk) {
    /* Remove falsey values */
    if (chunk === undefined || chunk === null || chunk === false || chunk === '') {
      return ruleSet;
    }
    /* Flatten ruleSet */
    if (Array.isArray(chunk)) {
      return [].concat(ruleSet, flatten(chunk, executionContext));
    }

    /* Handle other components */
    if (chunk.hasOwnProperty('styledComponentId')) {
      // $FlowFixMe not sure how to make this pass
      return [].concat(ruleSet, ['.' + chunk.styledComponentId]);
    }

    /* Either execute or defer the function */
    if (typeof chunk === 'function') {
      return executionContext ? ruleSet.concat.apply(ruleSet, flatten([chunk(executionContext)], executionContext)) : ruleSet.concat(chunk);
    }

    /* Handle objects */
    return ruleSet.concat(
    // $FlowFixMe have to add %checks somehow to isPlainObject
    isPlainObject(chunk) ? objToCss(chunk) : chunk.toString());
  }, []);
};

// 
// NOTE: This stylis instance is only used to split rules from SSR'd style tags