src/elements/Button/ButtonGroup.js
function ButtonGroup(props) {
  const {
    attached,
    basic,
    buttons,
    children,
    className,
    color,
    compact,
    content,
    floated,
    fluid,
    icon,
    inverted,
    labeled,
    negative,
    positive,
    primary,
    secondary,
    size,
    toggle,
    vertical,
    widths,
  } = props

  const classes = cx(
    'ui',
    color,
    size,
    useKeyOnly(basic, 'basic'),
    useKeyOnly(compact, 'compact'),
    useKeyOnly(fluid, 'fluid'),
    useKeyOnly(icon, 'icon'),
    useKeyOnly(inverted, 'inverted'),
    useKeyOnly(labeled, 'labeled'),
    useKeyOnly(negative, 'negative'),
    useKeyOnly(positive, 'positive'),
    useKeyOnly(primary, 'primary'),
    useKeyOnly(secondary, 'secondary'),
    useKeyOnly(toggle, 'toggle'),
    useKeyOnly(vertical, 'vertical'),
    useKeyOrValueAndKey(attached, 'attached'),
    useValueAndKey(floated, 'floated'),
    useWidthProp(widths),
    'buttons',
    className,
  )
  const rest = getUnhandledProps(ButtonGroup, props)
  const ElementType = getElementType(ButtonGroup, props)

  if (_.isNil(buttons)) {
    return (
      <ElementType {...rest} className={classes}>
        {childrenUtils.isNil(children) ? content : children}
      </ElementType>
    )
  }

  return (
    <ElementType {...rest} className={classes}>
      {_.map(buttons, button => Button.create(button))}
    </ElementType>
  )
}
function ButtonGroup(props) {
  const {
    attached,
    basic,
    buttons,
    children,
    className,
    color,
    compact,
    content,
    floated,
    fluid,
    icon,
    inverted,
    labeled,
    negative,
    positive,
    primary,
    secondary,
    size,
    toggle,
    vertical,
    widths,
  } = props

  const classes = cx(
    'ui',
    color,
    size,
    useKeyOnly(basic, 'basic'),
    useKeyOnly(compact, 'compact'),
    useKeyOnly(fluid, 'fluid'),
    useKeyOnly(icon, 'icon'),
    useKeyOnly(inverted, 'inverted'),
    useKeyOnly(labeled, 'labeled'),
    useKeyOnly(negative, 'negative'),
    useKeyOnly(positive, 'positive'),
    useKeyOnly(primary, 'primary'),
    useKeyOnly(secondary, 'secondary'),
    useKeyOnly(toggle, 'toggle'),
    useKeyOnly(vertical, 'vertical'),
    useKeyOrValueAndKey(attached, 'attached'),
    useValueAndKey(floated, 'floated'),
    useWidthProp(widths),
    'buttons',
    className,
  )
  const rest = getUnhandledProps(ButtonGroup, props)
  const ElementType = getElementType(ButtonGroup, props)

  if (_.isNil(buttons)) {
    return (
      <ElementType {...rest} className={classes}>
        {childrenUtils.isNil(children) ? content : children}
      </ElementType>
    )
  }

  return (
    <ElementType {...rest} className={classes}>
      {_.map(buttons, button => Button.create(button))}
    </ElementType>
  )
}
Buttons can be grouped.