only require imports that are necessary in selfContained

lib/6to5/transformation/modules/amd.js

@@ -87,7 +87,7 @@ AMDFormatter.prototype.importSpecifier = function (specifier, node, nodes) {
   var key = t.getSpecifierName(specifier);
   var ref = this._push(node);
 
-  if (_.contains(this.file.dynamicImports, node)) {
+  if (_.contains(this.file.dynamicImported, node)) {
     // Prevent unnecessary renaming of dynamic imports.
     this.ids[node.source.value] = key;
     return;

lib/6to5/transformation/modules/common.js

@@ -33,7 +33,7 @@ CommonJSFormatter.prototype.importSpecifier = function (specifier, node, nodes)
     var ref = util.template("require", {
       MODULE_NAME: node.source
     });
-    if (!_.contains(this.file.dynamicImports, node)) {
+    if (!_.contains(this.file.dynamicImported, node)) {
       ref = t.callExpression(this.file.addHelper("interop-require"), [ref]);
     }
     nodes.push(t.variableDeclaration("var", [t.variableDeclarator(variableName, ref)]));

lib/6to5/transformation/transformers/_module-formatter.js

@@ -1,11 +1,16 @@
 "use strict";
 
+var useStrict = require("../helpers/use-strict");
 var transform = require("../transform");
 
 exports.ast = {
   exit: function (ast, file) {
     if (!transform.transformers["es6.modules"].canRun(file)) return;
 
+    useStrict.wrap(ast.program, function () {
+      ast.program.body = file.dynamicImports.concat(ast.program.body);
+    });
+
     if (file.moduleFormatter.transform) {
       file.moduleFormatter.transform(ast);
     }

lib/6to5/transformation/transformers/es6/modules.js

@@ -2,12 +2,6 @@
 
 var t = require("../../../types");
 
-exports.ast = {
-  before: function (ast, file) {
-    ast.program.body = file.dynamicImports.concat(ast.program.body);
-  }
-};
-
 exports.ImportDeclaration = function (node, parent, scope, context, file) {
   var nodes = [];
 
@@ -20,8 +14,7 @@ exports.ImportDeclaration = function (node, parent, scope, context, file) {
   }
 
   if (nodes.length === 1) {
-    // inherit `_blockHoist`
-    // this for `_blockHoist` in File.prototype.addImport
+    // inherit `_blockHoist` - this is for `_blockHoist` in File.prototype.addImport
     nodes[0]._blockHoist = node._blockHoist;
   }
 
@@ -40,7 +33,7 @@ exports.ExportDeclaration = function (node, parent, scope, context, file) {
     }
 
     file.moduleFormatter.exportDeclaration(node, nodes, parent);
-  } else {
+  } else if (node.specifiers) {
     for (var i = 0; i < node.specifiers.length; i++) {
       file.moduleFormatter.exportSpecifier(node.specifiers[i], node, nodes, parent);
     }

lib/6to5/transformation/transformers/optional/self-contained.js

@@ -62,12 +62,20 @@ exports.optional = true;
 
 exports.ast = {
   enter: function (ast, file) {
-    file.set("runtimeIdentifier", file.addImport("6to5-runtime/helpers", "to5Runtime"));
-    file.set("coreIdentifier", file.addImport("6to5-runtime/core-js", "core"));
-    file.set("regeneratorIdentifier", file.addImport("6to5-runtime/regenerator", "regeneratorRuntime"));
+    file.setDynamic("runtimeIdentifier", function () {
+      return file.addImport("6to5-runtime/helpers", "to5Helpers");
+    });
+
+    file.setDynamic("coreIdentifier", function () {
+      return file.addImport("6to5-runtime/core-js", "core");
+    });
+
+    file.setDynamic("regeneratorIdentifier", function () {
+      return file.addImport("6to5-runtime/regenerator", "regeneratorRuntime");
+    });
   },
 
-  exit: function (ast, file) {
+  after: function (ast, file) {
     traverse(ast, astVisitor, null, file);
   }
 };

lib/6to5/transformation/transformers/optional/undeclared-variable-check.js

@@ -2,6 +2,6 @@ exports.optional = true;
 
 exports.Identifier = function (node, parent, scope, context, file) {
   if (!scope.has(node.name, true)) {
-    throw file.errorWithNode(node, "Reference to undeclared variable");
+    throw file.errorWithNode(node, "Reference to undeclared variable", ReferenceError);
   }
 };

test/fixtures/transformation/optional-self-contained/aliased-constructors/expected.js

@@ -1,11 +1,7 @@
 "use strict";
 
-var _to5Runtime = require("6to5-runtime/helpers");
-
 var _core = require("6to5-runtime/core-js");
 
-var _regeneratorRuntime = require("6to5-runtime/regenerator");
-
 obj.constructor === Object;
 obj.constructor === _core.Promise;
 

test/fixtures/transformation/optional-self-contained/es6-for-of/expected.js

@@ -1,11 +1,7 @@
 "use strict";
 
-var _to5Runtime = require("6to5-runtime/helpers");
-
 var _core = require("6to5-runtime/core-js");
 
-var _regeneratorRuntime = require("6to5-runtime/regenerator");
-
 for (var _iterator = _core.$for.getIterator(arr), _step; !(_step = _iterator.next()).done;) {
   var i = _step.value;
 }

test/fixtures/transformation/optional-self-contained/es7-array-comprehensions/expected.js

@@ -1,11 +1,7 @@
 "use strict";
 
-var _to5Runtime = require("6to5-runtime/helpers");
-
 var _core = require("6to5-runtime/core-js");
 
-var _regeneratorRuntime = require("6to5-runtime/regenerator");
-
 var arr = (function () {
   var _arr = [];
 

test/fixtures/transformation/optional-self-contained/full/expected.js

@@ -1,11 +1,11 @@
 "use strict";
 
-var _to5Runtime = require("6to5-runtime/helpers");
-
-var _core = require("6to5-runtime/core-js");
+var _to5Helpers = require("6to5-runtime/helpers");
 
 var _regeneratorRuntime = require("6to5-runtime/regenerator");
 
+var _core = require("6to5-runtime/core-js");
+
 var giveWord = _regeneratorRuntime.mark(function giveWord() {
   return _regeneratorRuntime.wrap(function giveWord$(context$1$0) {
     while (1) switch (context$1$0.prev = context$1$0.next) {
@@ -20,8 +20,8 @@ var giveWord = _regeneratorRuntime.mark(function giveWord() {
 });
 
 exports.giveWord = giveWord;
-var foo = _to5Runtime.interopRequire(require("someModule"));
+var foo = _to5Helpers.interopRequire(require("someModule"));
 
-var bar = _to5Runtime.interopRequireWildcard(require("someModule"));
+var bar = _to5Helpers.interopRequireWildcard(require("someModule"));
 
 var myWord = exports.myWord = _core.Symbol("abc");

test/fixtures/transformation/optional-self-contained/runtime-amd/expected.js

@@ -1,5 +1,5 @@
-define(["exports", "6to5-runtime/helpers", "6to5-runtime/core-js", "6to5-runtime/regenerator", "someModule"], function (exports, _to5Runtime, _core, _regeneratorRuntime, _someModule) {
+define(["exports", "someModule", "6to5-runtime/helpers"], function (exports, _someModule, _to5Helpers) {
   "use strict";
 
-  var foo = _to5Runtime.interopRequire(_someModule);
+  var foo = _to5Helpers.interopRequire(_someModule);
 });

test/fixtures/transformation/optional-self-contained/runtime-commonjs/expected.js

@@ -1,9 +1,5 @@
 "use strict";
 
-var _to5Runtime = require("6to5-runtime/helpers");
+var _to5Helpers = require("6to5-runtime/helpers");
 
-var _core = require("6to5-runtime/core-js");
-
-var _regeneratorRuntime = require("6to5-runtime/regenerator");
-
-var foo = _to5Runtime.interopRequireWildcard(require("someModule"));
+var foo = _to5Helpers.interopRequireWildcard(require("someModule"));