From 4fdcf685d3d6d4164d5e8556beb7bda5ea468682 Mon Sep 17 00:00:00 2001
From: Christopher Monsanto <chris@monsan.to>
Date: Tue, 13 Jan 2015 14:48:31 -0500
Subject: [PATCH] add loose transform for tagged template literals

---
 lib/6to5/file.js                                      |  1 +
 .../templates/tagged-template-literal-loose.js        |  4 ++++
 .../transformers/es6-template-literals.js             | 11 +++++++----
 3 files changed, 12 insertions(+), 4 deletions(-)
 create mode 100644 lib/6to5/transformation/templates/tagged-template-literal-loose.js

diff --git a/lib/6to5/file.js b/lib/6to5/file.js
index 2757dcb1e2..66c86d7fce 100644
--- a/lib/6to5/file.js
+++ b/lib/6to5/file.js
@@ -24,6 +24,7 @@ File.helpers = [
   "prototype-properties",
   "apply-constructor",
   "tagged-template-literal",
+  "tagged-template-literal-loose",
   "interop-require",
   "to-array",
   "sliced-to-array",
diff --git a/lib/6to5/transformation/templates/tagged-template-literal-loose.js b/lib/6to5/transformation/templates/tagged-template-literal-loose.js
new file mode 100644
index 0000000000..d8dd44bb7a
--- /dev/null
+++ b/lib/6to5/transformation/templates/tagged-template-literal-loose.js
@@ -0,0 +1,4 @@
+(function (strings, raw) {
+  strings.raw = raw;
+  return strings;
+});
diff --git a/lib/6to5/transformation/transformers/es6-template-literals.js b/lib/6to5/transformation/transformers/es6-template-literals.js
index 4be21d4269..81872a7766 100644
--- a/lib/6to5/transformation/transformers/es6-template-literals.js
+++ b/lib/6to5/transformation/transformers/es6-template-literals.js
@@ -17,11 +17,14 @@ exports.TaggedTemplateExpression = function (node, parent, file) {
     raw.push(t.literal(elem.value.raw));
   }
 
-  args.push(t.callExpression(file.addHelper("tagged-template-literal"), [
-    t.arrayExpression(strings),
-    t.arrayExpression(raw)
-  ]));
+  strings = t.arrayExpression(strings);
+  raw = t.arrayExpression(raw);
 
+  var template = file.isLoose("templateLiterals") ?
+      "tagged-template-literal-loose" :
+      "tagged-template-literal";
+
+  args.push(t.callExpression(file.addHelper(template), [strings, raw]));
   args = args.concat(quasi.expressions);
 
   return t.callExpression(node.tag, args);