@material-ui/lab/es/Skeleton/Skeleton.js

import _extends from "@babel/runtime/helpers/esm/extends";
import _objectWithoutPropertiesLoose from "@babel/runtime/helpers/esm/objectWithoutPropertiesLoose";
import * as React from 'react';
import clsx from 'clsx';
import PropTypes from 'prop-types';
import { alpha, withStyles } from '@material-ui/core/styles';
export const styles = theme => ({
  /* Styles applied to the root element. */
  root: {
    display: 'block',
    // Create a "on paper" color with sufficient contrast retaining the color
    backgroundColor: alpha(theme.palette.text.primary, theme.palette.type === 'light' ? 0.11 : 0.13),
    height: '1.2em'
  },

  /* Styles applied to the root element if `variant="text"`. */
  text: {
    marginTop: 0,
    marginBottom: 0,
    height: 'auto',
    transformOrigin: '0 60%',
    transform: 'scale(1, 0.60)',
    borderRadius: theme.shape.borderRadius,
    '&:empty:before': {
      content: '"\\00a0"'
    }
  },

  /* Styles applied to the root element if `variant="rect"`. */
  rect: {},

  /* Styles applied to the root element if `variant="circle"`. */
  circle: {
    borderRadius: '50%'
  },

  /* Styles applied to the root element if `animation="pulse"`. */
  pulse: {
    animation: '$pulse 1.5s ease-in-out 0.5s infinite'
  },
  '@keyframes pulse': {
    '0%': {
      opacity: 1
    },
    '50%': {
      opacity: 0.4
    },
    '100%': {
      opacity: 1
    }
  },

  /* Styles applied to the root element if `animation="wave"`. */
  wave: {
    position: 'relative',
    overflow: 'hidden',
    '&::after': {
      animation: '$wave 1.6s linear 0.5s infinite',
      background: `linear-gradient(90deg, transparent, ${theme.palette.action.hover}, transparent)`,
      content: '""',
      position: 'absolute',
      transform: 'translateX(-100%)',
      // Avoid flash during server-side hydration
      bottom: 0,
      left: 0,
      right: 0,
      top: 0
    }
  },
  '@keyframes wave': {
    '0%': {
      transform: 'translateX(-100%)'
    },
    '60%': {
      // +0.5s of delay between each loop
      transform: 'translateX(100%)'
    },
    '100%': {
      transform: 'translateX(100%)'
    }
  },

  /* Styles applied when the component is passed children. */
  withChildren: {
    '& > *': {
      visibility: 'hidden'
    }
  },

  /* Styles applied when the component is passed children and no width. */
  fitContent: {
    maxWidth: 'fit-content'
  },

  /* Styles applied when the component is passed children and no height. */
  heightAuto: {
    height: 'auto'
  }
});
const Skeleton = /*#__PURE__*/React.forwardRef(function Skeleton(props, ref) {
  const {
    animation = 'pulse',
    classes,
    className,
    component: Component = 'span',
    height,
    variant = 'text',
    width
  } = props,
        other = _objectWithoutPropertiesLoose(props, ["animation", "classes", "className", "component", "height", "variant", "width"]);

  const hasChildren = Boolean(other.children);
  return /*#__PURE__*/React.createElement(Component, _extends({
    ref: ref,
    className: clsx(classes.root, classes[variant], className, hasChildren && [classes.withChildren, !width && classes.fitContent, !height && classes.heightAuto], animation !== false && classes[animation])
  }, other, {
    style: _extends({
      width,
      height
    }, other.style)
  }));
});
process.env.NODE_ENV !== "production" ? Skeleton.propTypes = {
  /**
   * The animation.
   * If `false` the animation effect is disabled.
   */
  animation: PropTypes.oneOf(['pulse', 'wave', false]),

  /**
   * Optional children to infer width and height from.
   */
  children: PropTypes.node,

  /**
   * Override or extend the styles applied to the component.
   * See [CSS API](#css) below for more details.
   */
  classes: PropTypes.object.isRequired,

  /**
   * @ignore
   */
  className: PropTypes.string,

  /**
   * The component used for the root node.
   * Either a string to use a HTML element or a component.
   */
  component: PropTypes
  /* @typescript-to-proptypes-ignore */
  .elementType,

  /**
   * Height of the skeleton.
   * Useful when you don't want to adapt the skeleton to a text element but for instance a card.
   */
  height: PropTypes.oneOfType([PropTypes.number, PropTypes.string]),

  /**
   * The type of content that will be rendered.
   */
  variant: PropTypes.oneOf(['text', 'rect', 'circle']),

  /**
   * Width of the skeleton.
   * Useful when the skeleton is inside an inline element with no width of its own.
   */
  width: PropTypes.oneOfType([PropTypes.number, PropTypes.string])
} : void 0;
export default withStyles(styles, {
  name: 'MuiSkeleton'
})(Skeleton);