@material-ui/core/esm/styles/createBreakpoints.js

React components that implement Google's Material Design.

import _extends from "@babel/runtime/helpers/esm/extends";
import _objectWithoutProperties from "@babel/runtime/helpers/esm/objectWithoutProperties";
// Sorted ASC by size. That's important.
// It can't be configured as it's used statically for propTypes.
export var keys = ['xs', 'sm', 'md', 'lg', 'xl']; // Keep in mind that @media is inclusive by the CSS specification.

export default function createBreakpoints(breakpoints) {
  var _breakpoints$values = breakpoints.values,
      values = _breakpoints$values === void 0 ? {
    xs: 0,
    sm: 600,
    md: 960,
    lg: 1280,
    xl: 1920
  } : _breakpoints$values,
      _breakpoints$unit = breakpoints.unit,
      unit = _breakpoints$unit === void 0 ? 'px' : _breakpoints$unit,
      _breakpoints$step = breakpoints.step,
      step = _breakpoints$step === void 0 ? 5 : _breakpoints$step,
      other = _objectWithoutProperties(breakpoints, ["values", "unit", "step"]);

  function up(key) {
    var value = typeof values[key] === 'number' ? values[key] : key;
    return "@media (min-width:".concat(value).concat(unit, ")");
  }

  function down(key) {
    var endIndex = keys.indexOf(key) + 1;
    var upperbound = values[keys[endIndex]];

    if (endIndex === keys.length) {
      // xl down applies to all sizes
      return up('xs');
    }

    var value = typeof upperbound === 'number' && endIndex > 0 ? upperbound : key;
    return "@media (max-width:".concat(value - step / 100).concat(unit, ")");
  }

  function between(start, end) {
    var endIndex = keys.indexOf(end);

    if (endIndex === keys.length - 1) {
      return up(start);
    }

    return "@media (min-width:".concat(typeof values[start] === 'number' ? values[start] : start).concat(unit, ") and ") + "(max-width:".concat((endIndex !== -1 && typeof values[keys[endIndex + 1]] === 'number' ? values[keys[endIndex + 1]] : end) - step / 100).concat(unit, ")");
  }

  function only(key) {
    return between(key, key);
  }

  var warnedOnce = false;

  function width(key) {
    if (process.env.NODE_ENV !== 'production') {
      if (!warnedOnce) {
        warnedOnce = true;
        console.warn(["Material-UI: The `theme.breakpoints.width` utility is deprecated because it's redundant.", 'Use the `theme.breakpoints.values` instead.'].join('\n'));
      }
    }

    return values[key];
  }

  return _extends({
    keys: keys,
    values: values,
    up: up,
    down: down,
    between: between,
    only: only,
    width: width
  }, other);
}