index.js #1

"use strict";

exports.__esModule = true;

exports.default = function (path, file, helpers) {
  if (!helpers) {
    helpers = { wrapAsync: file };
    file = null;
  }
  path.traverse(awaitVisitor, {
    file: file,
    wrapAwait: helpers.wrapAwait
  });

  if (path.isClassMethod() || path.isObjectMethod()) {
    classOrObjectMethod(path, helpers.wrapAsync);
  } else {
    plainFunction(path, helpers.wrapAsync);
  }
};

var _babelHelperFunctionName = require("babel-helper-function-name");

var _babelHelperFunctionName2 = _interopRequireDefault(_babelHelperFunctionName);

var _babelTemplate = require("babel-template");

var _babelTemplate2 = _interopRequireDefault(_babelTemplate);

var _babelTypes = require("babel-types");

var t = _interopRequireWildcard(_babelTypes);

var _forAwait = require("./for-await");

var _forAwait2 = _interopRequireDefault(_forAwait);

function _interopRequireWildcard(obj) { if (obj && obj.__esModule) { return obj; } else { var newObj = {}; if (obj != null) { for (var key in obj) { if (Object.prototype.hasOwnProperty.call(obj, key)) newObj[key] = obj[key]; } } newObj.default = obj; return newObj; } }

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

var buildWrapper = (0, _babelTemplate2.default)("\n  (() => {\n    var REF = FUNCTION;\n    return function NAME(PARAMS) {\n      return REF.apply(this, arguments);\n    };\n  })\n");

var namedBuildWrapper = (0, _babelTemplate2.default)("\n  (() => {\n    var REF = FUNCTION;\n    function NAME(PARAMS) {\n      return REF.apply(this, arguments);\n    }\n    return NAME;\n  })\n");

var awaitVisitor = {
  Function: function Function(path) {
    if (path.isArrowFunctionExpression() && !path.node.async) {
      path.arrowFunctionToShadowed();
      return;
    }
    path.skip();
  },
  AwaitExpression: function AwaitExpression(_ref, _ref2) {
    var node = _ref.node;
    var wrapAwait = _ref2.wrapAwait;

    node.type = "YieldExpression";
    if (wrapAwait) {
      node.argument = t.callExpression(wrapAwait, [node.argument]);
    }
  },
  ForAwaitStatement: function ForAwaitStatement(path, _ref3) {
    var file = _ref3.file,
        wrapAwait = _ref3.wrapAwait;
    var node = path.node;


    var build = (0, _forAwait2.default)(path, {
      getAsyncIterator: file.addHelper("asyncIterator"),
      wrapAwait: wrapAwait
    });

    var declar = build.declar,
        loop = build.loop;

    var block = loop.body;

    path.ensureBlock();

    if (declar) {
      block.body.push(declar);
    }

    block.body = block.body.concat(node.body.body);

    t.inherits(loop, node);
    t.inherits(loop.body, node.body);

    if (build.replaceParent) {
      path.parentPath.replaceWithMultiple(build.node);
      path.remove();
    } else {
      path.replaceWithMultiple(build.node);
    }
  }
};

function classOrObjectMethod(path, callId) {
  var node = path.node;
  var body = node.body;

  node.async = false;

  var container = t.functionExpression(null, [], t.blockStatement(body.body), true);
  container.shadow = true;
  body.body = [t.returnStatement(t.callExpression(t.callExpression(callId, [container]), []))];

  node.generator = false;
}

function plainFunction(path, callId) {
  var node = path.node;
  var isDeclaration = path.isFunctionDeclaration();
  var asyncFnId = node.id;
  var wrapper = buildWrapper;

  if (path.isArrowFunctionExpression()) {
    path.arrowFunctionToShadowed();
  } else if (!isDeclaration && asyncFnId) {
    wrapper = namedBuildWrapper;
  }

  node.async = false;
  node.generator = true;

  node.id = null;

  if (isDeclaration) {
    node.type = "FunctionExpression";
  }

  var built = t.callExpression(callId, [node]);
  var container = wrapper({
    NAME: asyncFnId,
    REF: path.scope.generateUidIdentifier("ref"),
    FUNCTION: built,
    PARAMS: node.params.reduce(function (acc, param) {
      acc.done = acc.done || t.isAssignmentPattern(param) || t.isRestElement(param);

      if (!acc.done) {
        acc.params.push(path.scope.generateUidIdentifier("x"));
      }

      return acc;
    }, {
      params: [],
      done: false
    }).params
  }).expression;

  if (isDeclaration) {
    var declar = t.variableDeclaration("let", [t.variableDeclarator(t.identifier(asyncFnId.name), t.callExpression(container, []))]);
    declar._blockHoist = true;

    path.replaceWith(declar);
  } else {
    var retFunction = container.body.body[1].argument;
    if (!asyncFnId) {
      (0, _babelHelperFunctionName2.default)({
        node: retFunction,
        parent: path.parent,
        scope: path.scope
      });
    }

    if (!retFunction || retFunction.id || node.params.length) {
      path.replaceWith(t.callExpression(container, []));
    } else {
      path.replaceWith(built);
    }
  }
}

module.exports = exports["default"];