jmd-scripts/dist/config/babelrc.js

CLI for common scripts for my projects

"use strict";

const browserslist = require('browserslist');

const semver = require('semver');

const {
  ifAnyDep,
  parseEnv,
  appDirectory,
  pkg
} = require('../utils');

const isTest = (process.env.BABEL_ENV || process.env.NODE_ENV) === 'test';
const isPreact = parseEnv('BUILD_PREACT', false);
const isRollup = parseEnv('BUILD_ROLLUP', false);
const isUMD = process.env.BUILD_FORMAT === 'umd';
const isWebpack = parseEnv('BUILD_WEBPACK', false);
const treeshake = parseEnv('BUILD_TREESHAKE', isRollup || isWebpack);
const alias = parseEnv('BUILD_ALIAS', isPreact ? {
  react: 'preact'
} : null);
/**
 * use the strategy declared by browserslist to load browsers configuration.
 * fallback to the default if don't found custom configuration
 * @see https://github.com/browserslist/browserslist/blob/master/node.js#L139
 */

const browsersConfig = browserslist.loadConfig({
  path: appDirectory
}) || ['ie 10', 'ios 7'];
const envTargets = isTest ? {
  node: 'current'
} : isWebpack || isRollup ? {
  browsers: browsersConfig
} : {
  node: getNodeVersion(pkg)
};
const envOptions = {
  modules: false,
  loose: true,
  targets: envTargets
};

module.exports = () => ({
  presets: [[require.resolve('@babel/preset-env'), envOptions], ifAnyDep(['react', 'preact'], [require.resolve('@babel/preset-react'), {
    pragma: isPreact ? 'React.h' : undefined
  }])].filter(Boolean),
  plugins: [require.resolve('babel-plugin-macros'), alias ? [require.resolve('babel-plugin-module-resolver'), {
    root: ['./src'],
    alias
  }] : null, [require.resolve('babel-plugin-transform-react-remove-prop-types'), isPreact ? {
    removeImport: true
  } : {
    mode: 'unsafe-wrap'
  }], isUMD ? require.resolve('babel-plugin-transform-inline-environment-variables') : null, [require.resolve('@babel/plugin-proposal-class-properties'), {
    loose: true
  }], require.resolve('@babel/plugin-proposal-object-rest-spread'), require.resolve('babel-plugin-minify-dead-code-elimination'), treeshake ? null : require.resolve('@babel/plugin-transform-modules-commonjs')].filter(Boolean)
});

function getNodeVersion({
  engines: {
    node: nodeVersion = '8'
  } = {}
}) {
  const oldestVersion = semver.validRange(nodeVersion).replace(/[>=<|]/g, ' ').split(' ').filter(Boolean).sort(semver.compare)[0];

  if (!oldestVersion) {
    throw new Error(`Unable to determine the oldest version in the range in your package.json at engines.node: "${nodeVersion}". Please attempt to make it less ambiguous.`);
  }

  return oldestVersion;
}