storybook/code/renderers/react/src/__test__/Button.tsx

import React from 'react';
import './button.css';

export interface ButtonProps {
  /**
   * Is this the principal call to action on the page?
   */
  primary?: boolean;
  /**
   * What background color to use
   */
  backgroundColor?: string;
  /**
   * How large should the button be?
   */
  size?: 'small' | 'medium' | 'large';
  /**
   * Button contents
   */
  children: React.ReactNode;
  /**
   * Optional click handler
   */
  onClick?: () => void;
}

/**
 * Primary UI component for user interaction
 */
export const Button: React.FC<ButtonProps> = (props) => {
  const { primary = false, size = 'medium', backgroundColor, children, onClick } = props;
  const mode = primary ? 'storybook-button--primary' : 'storybook-button--secondary';
  return (
    <button
      type="button"
      className={['storybook-button', `storybook-button--${size}`, mode].join(' ')}
      style={{ backgroundColor }}
      onClick={onClick}
    >
      {children}
    </button>
  );
};