old_contents: import React from 'react'
  import { Link } from 'react-router-dom'
  
  import cn from 'utils/cn'
  
  import './button.css'
  
  const Button = ({
    children,
    to,
    href,
    small,
    ghost,
    disabled,
  }) => {
    const Tag = to ? Link
      : href ? 'a'
      : 'button'
  
    return (
      <Tag
        to={to}
        href={href}
        disabled={disabled}
        className={cn(
          'button',
          small && 'button--small',
          ghost && 'button--ghost',
        )}
        >
        {children}
      </Tag>
    )
  }
  
  export default Button
  
new_contents: import React from 'react'
  import { Link } from 'react-router-dom'
  
  import cn from 'utils/cn'
  
  import './button.css'
  
  const Button = ({
    children,
    to,
    href,
    small,
    ghost,
    disabled,
    onClick,
  }) => {
    const Tag = to ? Link
      : href ? 'a'
      : 'button'
  
    return (
      <Tag
        to={to}
        href={href}
        disabled={disabled}
        className={cn(
          'button',
          small && 'button--small',
          ghost && 'button--ghost',
        )}
        onClick={onClick}
        >
        {children}
      </Tag>
    )
  }
  
  export default Button
  
subject: add onClick prop