From e8237910e89218d86225233493a74e75664da2a6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alu=C3=ADsio=20Augusto=20Silva=20Gon=C3=A7alves?=
 <aluisio@aasg.name>
Date: Wed, 14 Jan 2015 01:39:37 -0200
Subject: [PATCH 1/4] Add a transformer to import the runtime from a file

The `externalRuntime` optional transformer can be used in conjunction
with the `runtime` option to import and use the runtime from a module
instead of polluting the global environment.
---
 lib/6to5/transformation/modules/amd.js               |  2 +-
 lib/6to5/transformation/modules/common.js            | 12 +++++-------
 lib/6to5/transformation/transform.js                 |  1 +
 .../transformers/optional-external-runtime.js        | 11 +++++++++++
 4 files changed, 18 insertions(+), 8 deletions(-)
 create mode 100644 lib/6to5/transformation/transformers/optional-external-runtime.js

diff --git a/lib/6to5/transformation/modules/amd.js b/lib/6to5/transformation/modules/amd.js
index 3940c9d18d..d97ba66118 100644
--- a/lib/6to5/transformation/modules/amd.js
+++ b/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 (t.isImportBatchSpecifier(specifier)) {
+  if (t.isImportBatchSpecifier(specifier) || node._noInteropRequire) {
     // import * as bar from "foo";
   } else if (t.isSpecifierDefault(specifier) && !this.noInteropRequire) {
     // import foo from "foo";
diff --git a/lib/6to5/transformation/modules/common.js b/lib/6to5/transformation/modules/common.js
index 8e6044f2e9..c44f34078f 100644
--- a/lib/6to5/transformation/modules/common.js
+++ b/lib/6to5/transformation/modules/common.js
@@ -26,13 +26,11 @@ CommonJSFormatter.prototype.importSpecifier = function (specifier, node, nodes)
 
   // import foo from "foo";
   if (t.isSpecifierDefault(specifier)) {
-    nodes.push(t.variableDeclaration("var", [
-      t.variableDeclarator(variableName,
-        t.callExpression(this.file.addHelper("interop-require"), [util.template("require", {
-          MODULE_NAME: node.source
-        })])
-      )
-    ]));
+    var ref = util.template("require", {MODULE_NAME: node.source});
+    if (!node._noInteropRequire) {
+      ref = t.callExpression(this.file.addHelper("interop-require"), [ref]);
+    }
+    nodes.push(t.variableDeclaration("var", [t.variableDeclarator(variableName, ref)]));
   } else {
     if (specifier.type === "ImportBatchSpecifier") {
       // import * as bar from "foo";
diff --git a/lib/6to5/transformation/transform.js b/lib/6to5/transformation/transform.js
index 2a5cbb26a2..a1c7a104ac 100644
--- a/lib/6to5/transformation/transform.js
+++ b/lib/6to5/transformation/transform.js
@@ -95,6 +95,7 @@ _.each({
   _moduleFormatter:          require("./transformers/_module-formatter"),
 
   typeofSymbol:              require("./transformers/optional-typeof-symbol"),
+  externalRuntime:           require("./transformers/optional-external-runtime"),
   coreAliasing:              require("./transformers/optional-core-aliasing"),
   undefinedToVoid:           require("./transformers/optional-undefined-to-void"),
 
diff --git a/lib/6to5/transformation/transformers/optional-external-runtime.js b/lib/6to5/transformation/transformers/optional-external-runtime.js
new file mode 100644
index 0000000000..a2f52667cf
--- /dev/null
+++ b/lib/6to5/transformation/transformers/optional-external-runtime.js
@@ -0,0 +1,11 @@
+exports.optional = true;
+
+// In theory, it would be more appropriate to do this in `manipulateOptions`,
+// but we need an identifier for the import and we can't get that before the
+// AST is built.
+exports.ast = {
+  enter: function (ast, file) {
+    file.opts.runtime = file.addImport(file.opts.runtime, "to5Runtime").name;
+    file.dynamicImports[file.dynamicImports.length - 1]._noInteropRequire = true;
+  }
+};

From e9a024e58a14c8fdc452425714c8adec83b01544 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alu=C3=ADsio=20Augusto=20Silva=20Gon=C3=A7alves?=
 <aluisio@aasg.name>
Date: Wed, 14 Jan 2015 02:38:31 -0200
Subject: [PATCH 2/4] Add simple test for externalRuntime transformer

Just import a module namespace and see what happens.
---
 .../transformation/optional-external-runtime/basic/actual.js | 1 +
 .../optional-external-runtime/basic/expected.js              | 5 +++++
 .../transformation/optional-external-runtime/options.json    | 4 ++++
 3 files changed, 10 insertions(+)
 create mode 100644 test/fixtures/transformation/optional-external-runtime/basic/actual.js
 create mode 100644 test/fixtures/transformation/optional-external-runtime/basic/expected.js
 create mode 100644 test/fixtures/transformation/optional-external-runtime/options.json

diff --git a/test/fixtures/transformation/optional-external-runtime/basic/actual.js b/test/fixtures/transformation/optional-external-runtime/basic/actual.js
new file mode 100644
index 0000000000..9e9515cece
--- /dev/null
+++ b/test/fixtures/transformation/optional-external-runtime/basic/actual.js
@@ -0,0 +1 @@
+import * as foo from "someModule";
diff --git a/test/fixtures/transformation/optional-external-runtime/basic/expected.js b/test/fixtures/transformation/optional-external-runtime/basic/expected.js
new file mode 100644
index 0000000000..b10bbe6f09
--- /dev/null
+++ b/test/fixtures/transformation/optional-external-runtime/basic/expected.js
@@ -0,0 +1,5 @@
+"use strict";
+
+var _to5Runtime = require("6to5-runtime");
+
+var foo = _to5Runtime.interopRequireWildcard(require("someModule"));
diff --git a/test/fixtures/transformation/optional-external-runtime/options.json b/test/fixtures/transformation/optional-external-runtime/options.json
new file mode 100644
index 0000000000..44c5164a67
--- /dev/null
+++ b/test/fixtures/transformation/optional-external-runtime/options.json
@@ -0,0 +1,4 @@
+{
+  "runtime": "6to5-runtime",
+  "optional": ["externalRuntime"]
+}

From 84ee0efe32c1ad17b869c2f7a52d451c09734379 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alu=C3=ADsio=20Augusto=20Silva=20Gon=C3=A7alves?=
 <aluisio@aasg.name>
Date: Wed, 14 Jan 2015 12:13:08 -0200
Subject: [PATCH 3/4] Add test for externalRuntime with AMD modules

---
 .../transformation/optional-external-runtime/amd/actual.js  | 1 +
 .../optional-external-runtime/amd/expected.js               | 6 ++++++
 .../optional-external-runtime/amd/options.json              | 3 +++
 .../optional-external-runtime/{basic => commonjs}/actual.js | 0
 .../{basic => commonjs}/expected.js                         | 0
 5 files changed, 10 insertions(+)
 create mode 100644 test/fixtures/transformation/optional-external-runtime/amd/actual.js
 create mode 100644 test/fixtures/transformation/optional-external-runtime/amd/expected.js
 create mode 100644 test/fixtures/transformation/optional-external-runtime/amd/options.json
 rename test/fixtures/transformation/optional-external-runtime/{basic => commonjs}/actual.js (100%)
 rename test/fixtures/transformation/optional-external-runtime/{basic => commonjs}/expected.js (100%)

diff --git a/test/fixtures/transformation/optional-external-runtime/amd/actual.js b/test/fixtures/transformation/optional-external-runtime/amd/actual.js
new file mode 100644
index 0000000000..09493dc9be
--- /dev/null
+++ b/test/fixtures/transformation/optional-external-runtime/amd/actual.js
@@ -0,0 +1 @@
+import foo from "someModule";
diff --git a/test/fixtures/transformation/optional-external-runtime/amd/expected.js b/test/fixtures/transformation/optional-external-runtime/amd/expected.js
new file mode 100644
index 0000000000..20e759af12
--- /dev/null
+++ b/test/fixtures/transformation/optional-external-runtime/amd/expected.js
@@ -0,0 +1,6 @@
+define(["exports", "6to5-runtime", "someModule"], function (exports, _to5Runtime2, _someModule) {
+  "use strict";
+
+  var _to5Runtime = _to5Runtime2;
+  var foo = _to5Runtime.interopRequire(_someModule);
+});
diff --git a/test/fixtures/transformation/optional-external-runtime/amd/options.json b/test/fixtures/transformation/optional-external-runtime/amd/options.json
new file mode 100644
index 0000000000..b76b119f33
--- /dev/null
+++ b/test/fixtures/transformation/optional-external-runtime/amd/options.json
@@ -0,0 +1,3 @@
+{
+  "modules": "amd"
+}
diff --git a/test/fixtures/transformation/optional-external-runtime/basic/actual.js b/test/fixtures/transformation/optional-external-runtime/commonjs/actual.js
similarity index 100%
rename from test/fixtures/transformation/optional-external-runtime/basic/actual.js
rename to test/fixtures/transformation/optional-external-runtime/commonjs/actual.js
diff --git a/test/fixtures/transformation/optional-external-runtime/basic/expected.js b/test/fixtures/transformation/optional-external-runtime/commonjs/expected.js
similarity index 100%
rename from test/fixtures/transformation/optional-external-runtime/basic/expected.js
rename to test/fixtures/transformation/optional-external-runtime/commonjs/expected.js

From e985d8b25de9f3b281a8a700c34c64099acc74b6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alu=C3=ADsio=20Augusto=20Silva=20Gon=C3=A7alves?=
 <aluisio@aasg.name>
Date: Wed, 14 Jan 2015 14:00:33 -0200
Subject: [PATCH 4/4] Don't use interopRequire for dynamic imports

They don't need it at all and this also allows use of `externalRuntime`
without fear of the runtime ending up being loaded after it's used.
---
 lib/6to5/transformation/modules/amd.js                      | 2 +-
 lib/6to5/transformation/modules/common.js                   | 3 ++-
 .../transformers/optional-external-runtime.js               | 1 -
 .../optional-bluebird-coroutines/expression/expected.js     | 6 +-----
 .../optional-bluebird-coroutines/statement/expected.js      | 6 +-----
 .../optional-core-aliasing/aliased-constructors/expected.js | 6 +-----
 .../optional-core-aliasing/es6-destructuring/expected.js    | 6 +-----
 .../optional-core-aliasing/es6-for-of/expected.js           | 6 +-----
 .../optional-core-aliasing/es6-spread/expected.js           | 6 +-----
 .../es7-array-comprehensions/expected.js                    | 6 +-----
 10 files changed, 10 insertions(+), 38 deletions(-)

diff --git a/lib/6to5/transformation/modules/amd.js b/lib/6to5/transformation/modules/amd.js
index d97ba66118..0eb61407b2 100644
--- a/lib/6to5/transformation/modules/amd.js
+++ b/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 (t.isImportBatchSpecifier(specifier) || node._noInteropRequire) {
+  if (t.isImportBatchSpecifier(specifier) || _.contains(this.file.dynamicImports, node)) {
     // import * as bar from "foo";
   } else if (t.isSpecifierDefault(specifier) && !this.noInteropRequire) {
     // import foo from "foo";
diff --git a/lib/6to5/transformation/modules/common.js b/lib/6to5/transformation/modules/common.js
index c44f34078f..950b35790e 100644
--- a/lib/6to5/transformation/modules/common.js
+++ b/lib/6to5/transformation/modules/common.js
@@ -6,6 +6,7 @@ var DefaultFormatter = require("./_default");
 var traverse         = require("../../traverse");
 var util             = require("../../util");
 var t                = require("../../types");
+var _                = require("lodash");
 
 function CommonJSFormatter(file) {
   DefaultFormatter.apply(this, arguments);
@@ -27,7 +28,7 @@ CommonJSFormatter.prototype.importSpecifier = function (specifier, node, nodes)
   // import foo from "foo";
   if (t.isSpecifierDefault(specifier)) {
     var ref = util.template("require", {MODULE_NAME: node.source});
-    if (!node._noInteropRequire) {
+    if (!_.contains(this.file.dynamicImports, node)) {
       ref = t.callExpression(this.file.addHelper("interop-require"), [ref]);
     }
     nodes.push(t.variableDeclaration("var", [t.variableDeclarator(variableName, ref)]));
diff --git a/lib/6to5/transformation/transformers/optional-external-runtime.js b/lib/6to5/transformation/transformers/optional-external-runtime.js
index a2f52667cf..ff39454e4d 100644
--- a/lib/6to5/transformation/transformers/optional-external-runtime.js
+++ b/lib/6to5/transformation/transformers/optional-external-runtime.js
@@ -6,6 +6,5 @@ exports.optional = true;
 exports.ast = {
   enter: function (ast, file) {
     file.opts.runtime = file.addImport(file.opts.runtime, "to5Runtime").name;
-    file.dynamicImports[file.dynamicImports.length - 1]._noInteropRequire = true;
   }
 };
diff --git a/test/fixtures/transformation/optional-bluebird-coroutines/expression/expected.js b/test/fixtures/transformation/optional-bluebird-coroutines/expression/expected.js
index 13943a98de..ed68858b19 100644
--- a/test/fixtures/transformation/optional-bluebird-coroutines/expression/expected.js
+++ b/test/fixtures/transformation/optional-bluebird-coroutines/expression/expected.js
@@ -1,10 +1,6 @@
 "use strict";
 
-var _interopRequire = function (obj) {
-  return obj && (obj["default"] || obj);
-};
-
-var _bluebird = _interopRequire(require("bluebird"));
+var _bluebird = require("bluebird");
 
 var foo = _bluebird.coroutine(function* () {
   var wat = yield bar();
diff --git a/test/fixtures/transformation/optional-bluebird-coroutines/statement/expected.js b/test/fixtures/transformation/optional-bluebird-coroutines/statement/expected.js
index 9b200b29f0..c5dbaaf5d1 100644
--- a/test/fixtures/transformation/optional-bluebird-coroutines/statement/expected.js
+++ b/test/fixtures/transformation/optional-bluebird-coroutines/statement/expected.js
@@ -1,10 +1,6 @@
 "use strict";
 
-var _interopRequire = function (obj) {
-  return obj && (obj["default"] || obj);
-};
-
-var _bluebird = _interopRequire(require("bluebird"));
+var _bluebird = require("bluebird");
 
 var foo = _bluebird.coroutine(function* foo() {
   var wat = yield bar();
diff --git a/test/fixtures/transformation/optional-core-aliasing/aliased-constructors/expected.js b/test/fixtures/transformation/optional-core-aliasing/aliased-constructors/expected.js
index 7c6e3f9ba2..8c6ff60ed1 100644
--- a/test/fixtures/transformation/optional-core-aliasing/aliased-constructors/expected.js
+++ b/test/fixtures/transformation/optional-core-aliasing/aliased-constructors/expected.js
@@ -1,10 +1,6 @@
 "use strict";
 
-var _interopRequire = function (obj) {
-  return obj && (obj["default"] || obj);
-};
-
-var _core = _interopRequire(require("core-js/library"));
+var _core = require("core-js/library");
 
 obj.constructor === Object;
 obj.constructor === _core.Promise;
diff --git a/test/fixtures/transformation/optional-core-aliasing/es6-destructuring/expected.js b/test/fixtures/transformation/optional-core-aliasing/es6-destructuring/expected.js
index fc43ff5423..15e3ce78b9 100644
--- a/test/fixtures/transformation/optional-core-aliasing/es6-destructuring/expected.js
+++ b/test/fixtures/transformation/optional-core-aliasing/es6-destructuring/expected.js
@@ -16,11 +16,7 @@ var _slicedToArray = function (arr, i) {
   }
 };
 
-var _interopRequire = function (obj) {
-  return obj && (obj["default"] || obj);
-};
-
-var _core = _interopRequire(require("core-js/library"));
+var _core = require("core-js/library");
 
 var _ref = ["hello", [", ", "junk"], ["world"]];
 
diff --git a/test/fixtures/transformation/optional-core-aliasing/es6-for-of/expected.js b/test/fixtures/transformation/optional-core-aliasing/es6-for-of/expected.js
index 3bf1f53a05..2669fd4d0c 100644
--- a/test/fixtures/transformation/optional-core-aliasing/es6-for-of/expected.js
+++ b/test/fixtures/transformation/optional-core-aliasing/es6-for-of/expected.js
@@ -1,10 +1,6 @@
 "use strict";
 
-var _interopRequire = function (obj) {
-  return obj && (obj["default"] || obj);
-};
-
-var _core = _interopRequire(require("core-js/library"));
+var _core = require("core-js/library");
 
 for (var _iterator = _core.$for.getIterator(arr), _step; !(_step = _iterator.next()).done;) {
   var i = _step.value;
diff --git a/test/fixtures/transformation/optional-core-aliasing/es6-spread/expected.js b/test/fixtures/transformation/optional-core-aliasing/es6-spread/expected.js
index 4d00347582..2a41ccd997 100644
--- a/test/fixtures/transformation/optional-core-aliasing/es6-spread/expected.js
+++ b/test/fixtures/transformation/optional-core-aliasing/es6-spread/expected.js
@@ -4,10 +4,6 @@ var _toArray = function (arr) {
   return Array.isArray(arr) ? arr : _core.Array.from(arr);
 };
 
-var _interopRequire = function (obj) {
-  return obj && (obj["default"] || obj);
-};
-
-var _core = _interopRequire(require("core-js/library"));
+var _core = require("core-js/library");
 
 var lyrics = ["head", "and", "toes"].concat(_toArray(parts));
diff --git a/test/fixtures/transformation/optional-core-aliasing/es7-array-comprehensions/expected.js b/test/fixtures/transformation/optional-core-aliasing/es7-array-comprehensions/expected.js
index 01333ca8f9..0bf67a612a 100644
--- a/test/fixtures/transformation/optional-core-aliasing/es7-array-comprehensions/expected.js
+++ b/test/fixtures/transformation/optional-core-aliasing/es7-array-comprehensions/expected.js
@@ -1,10 +1,6 @@
 "use strict";
 
-var _interopRequire = function (obj) {
-  return obj && (obj["default"] || obj);
-};
-
-var _core = _interopRequire(require("core-js/library"));
+var _core = require("core-js/library");
 
 var arr = (function () {
   var _arr = [];