babel-core/lib/babel/tools/build-external-helpers.js

Turn ES6 code into readable vanilla ES5 with source maps

"use strict";

var _interopRequireWildcard = function (obj) { return obj && obj.__esModule ? obj : { "default": obj }; };

var _interopRequire = function (obj) { return obj && obj.__esModule ? obj["default"] : obj; };

var generator = _interopRequire(require("../generation"));

var messages = _interopRequireWildcard(require("../messages"));

var util = _interopRequireWildcard(require("../util"));

var File = _interopRequire(require("../transformation/file"));

var each = _interopRequire(require("lodash/collection/each"));

var t = _interopRequireWildcard(require("../types"));

function buildGlobal(namespace, builder) {
  var body = [];
  var container = t.functionExpression(null, [t.identifier("global")], t.blockStatement(body));
  var tree = t.program([t.expressionStatement(t.callExpression(container, [util.template("helper-self-global")]))]);

  body.push(t.variableDeclaration("var", [t.variableDeclarator(namespace, t.assignmentExpression("=", t.memberExpression(t.identifier("global"), namespace), t.objectExpression([])))]));

  builder(body);

  return tree;
}

function buildUmd(namespace, builder) {
  var body = [];
  body.push(t.variableDeclaration("var", [t.variableDeclarator(namespace, t.identifier("global"))]));

  builder(body);

  var container = util.template("umd-commonjs-strict", {
    FACTORY_PARAMETERS: t.identifier("global"),
    BROWSER_ARGUMENTS: t.assignmentExpression("=", t.memberExpression(t.identifier("root"), namespace), t.objectExpression({})),
    COMMON_ARGUMENTS: t.identifier("exports"),
    AMD_ARGUMENTS: t.arrayExpression([t.literal("exports")]),
    FACTORY_BODY: body,
    UMD_ROOT: t.identifier("this")
  });
  return t.program([container]);
}

function buildVar(namespace, builder) {
  var body = [];
  body.push(t.variableDeclaration("var", [t.variableDeclarator(namespace, t.objectExpression({}))]));
  builder(body);
  return t.program(body);
}

function buildHelpers(body, namespace, whitelist) {
  each(File.helpers, function (name) {
    if (whitelist && whitelist.indexOf(name) === -1) return;

    var key = t.identifier(t.toIdentifier(name));
    body.push(t.expressionStatement(t.assignmentExpression("=", t.memberExpression(namespace, key), util.template("helper-" + name))));
  });
}

module.exports = function (whitelist) {
  var outputType = arguments[1] === undefined ? "global" : arguments[1];

  var namespace = t.identifier("babelHelpers");

  var builder = function builder(body) {
    return buildHelpers(body, namespace, whitelist);
  };

  var tree;

  var build = ({
    global: buildGlobal,
    umd: buildUmd,
    "var": buildVar
  })[outputType];

  if (build) {
    tree = build(namespace, builder);
  } else {
    throw new Error(messages.get("unsupportedOutputType", outputType));
  }

  return generator(tree).code;
};