StorableConfigBase::castValue

protected StorableConfigBase::castValue($key, $value)

protected function castValue($key, $value) {
  $element = $this->getSchemaWrapper()->get($key);
  // Do not cast value if it is unknown or defined to be ignored.
  if ($element && ($element instanceof Undefined || $element instanceof Ignore)) {
    // Do validate the value (may throw UnsupportedDataTypeConfigException)
    // to ensure unsupported types are not supported in this case either.
    $this->validateValue($key, $value);
    return $value;
  }
  if (is_scalar($value) || $value === NULL) {
    if ($element && $element instanceof PrimitiveInterface) {
      // Special handling for integers and floats since the configuration
      // system is primarily concerned with saving values from the Form API
      // we have to special case the meaning of an empty string for numeric
      // types. In PHP this would be casted to a 0 but for the purposes of
      // configuration we need to treat this as a NULL.
      $empty_value = $value === '' && ($element instanceof IntegerInterface || $element instanceof FloatInterface);

      if ($value === NULL || $empty_value) {
        $value = NULL;
      }
      else {
        $value = $element->getCastedValue();
      }
    }
  }
  else {
    // Throw exception on any non-scalar or non-array value.
    if (!is_array($value)) {
      throw new UnsupportedDataTypeConfigException("Invalid data type for config element {$this->getName()}:$key");
    }
    // Recurse into any nested keys.
    foreach ($value as $nested_value_key => $nested_value) {
      $value[$nested_value_key] = $this->castValue($key . '.' . $nested_value_key, $nested_value);
    }
  }
  return $value;
}