@parcel/transformer-babel/lib/utils.js

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.enginesToBabelTargets = enginesToBabelTargets;
exports.getMinSemver = getMinSemver;

var _assert = _interopRequireDefault(require("assert"));

var _semver = _interopRequireDefault(require("semver"));

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

// List of browsers to exclude when the esmodule target is specified.
// Based on https://caniuse.com/#feat=es6-module
const ESMODULE_BROWSERS = ['not ie <= 11', 'not edge < 16', 'not firefox < 60', 'not chrome < 61', 'not safari < 11', 'not opera < 48', 'not ios_saf < 11', 'not op_mini all', 'not android < 76', 'not blackberry > 0', 'not op_mob > 0', 'not and_chr < 76', 'not and_ff < 68', 'not ie_mob > 0', 'not and_uc > 0', 'not samsung < 8.2', 'not and_qq > 0', 'not baidu > 0', 'not kaios > 0'];

function enginesToBabelTargets(env) {
  // "Targets" is the name @babel/preset-env uses for what Parcel calls engines.
  // This should not be confused with Parcel's own targets.
  // Unlike Parcel's engines, @babel/preset-env expects to work with minimum
  // versions, not semver ranges, of its targets.
  let targets = {};

  for (let engineName of Object.keys(env.engines)) {
    let engineValue = env.engines[engineName]; // if the engineValue is a string, it might be a semver range. Use the minimum
    // possible version instead.

    if (engineName === 'browsers') {
      targets[engineName] = engineValue;
    } else {
      var _minVersion;

      (0, _assert.default)(typeof engineValue === 'string');
      let minVersion = getMinSemver(engineValue);
      targets[engineName] = (_minVersion = minVersion) !== null && _minVersion !== void 0 ? _minVersion : engineValue;
    }
  }

  if (env.outputFormat === 'esmodule' && env.isBrowser()) {
    // If there is already a browsers target, add a blacklist to exclude
    // instead of using babel's esmodules target. This allows specifying
    // a newer set of browsers than the baseline esmodule support list.
    // See https://github.com/babel/babel/issues/8809.
    if (targets.browsers) {
      let browsers = Array.isArray(targets.browsers) ? targets.browsers : [targets.browsers];
      targets.browsers = [...browsers, ...ESMODULE_BROWSERS];
    } else {
      targets.esmodules = true;
    }
  }

  return targets;
} // TODO: Replace with `minVersion` (https://github.com/npm/node-semver#ranges-1)
//       once semver has been upgraded across Parcel.


function getMinSemver(version) {
  try {
    let range = new _semver.default.Range(version);
    let sorted = range.set.sort((a, b) => a[0].semver.compare(b[0].semver));
    return sorted[0][0].semver.version;
  } catch (err) {
    return null;
  }
}