use acorns preserveParens

lib/6to5/generation/generators/expressions.js

@@ -17,6 +17,12 @@ exports.UnaryExpression = function (node, print) {
   print(node.argument);
 };
 
+exports.ParenthesizedExpression = function (node, print) {
+  this.push("(");
+  print(node.expression);
+  this.push(")");
+};
+
 exports.UpdateExpression = function (node, print) {
   if (node.prefix) {
     this.push(node.operator);
@@ -35,7 +41,7 @@ exports.ConditionalExpression = function (node, print) {
   print(node.alternate);
 };
 
-exports.NewExpression = function (node, print, parent) {
+exports.NewExpression = function (node, print) {
   this.push("new ");
   print(node.callee);
   this.push("(");

lib/6to5/transformation/transformers/array-comprehension.js

@@ -25,7 +25,7 @@ var multiple = function (node, file) {
   });
   container._aliasFunction = true;
 
-  var block = container.callee.body;
+  var block = container.callee.expression.body;
   var body  = block.body;
 
   var returnStatement = body.pop();

lib/6to5/transformation/transformers/classes.js

@@ -40,7 +40,7 @@ var buildClass = function (node, file, scope) {
     CLASS_NAME: className
   });
 
-  var block       = container.callee.body;
+  var block       = container.callee.expression.body;
   var body        = block.body;
   var constructor = body[0].declarations[0].init;
 
@@ -52,7 +52,7 @@ var buildClass = function (node, file, scope) {
     body.push(t.expressionStatement(t.callExpression(file.addDeclaration("extends"), [className, superName])));
 
     container.arguments.push(superClassArgument);
-    container.callee.params.push(superClassCallee);
+    container.callee.expression.params.push(superClassCallee);
   }
 
   buildClassBody({
@@ -180,8 +180,7 @@ var superIdentifier = function (superName, methodNode, node, parent) {
 };
 
 var replaceInstanceSuperReferences = function (superName, methodNode) {
-  var methodName = methodNode.key;
-  var method     = methodNode.value;
+  var method = methodNode.value;
 
   superName = superName || t.identifier("Function");
 

lib/6to5/transformation/transformers/computed-property-names.js

@@ -26,7 +26,7 @@ exports.ObjectExpression = function (node, parent, file) {
     OBJECT: node
   });
 
-  var containerCallee = container.callee;
+  var containerCallee = container.callee.expression;
   var containerBody = containerCallee.body.body;
 
   containerCallee._aliasFunction = "arrows";

lib/6to5/transformation/transformers/template-literals.js

@@ -28,7 +28,10 @@ exports.TemplateLiteral = function (node) {
     nodes.push(t.literal(elem.value.raw));
 
     var expr = node.expressions.shift();
-    if (expr) nodes.push(expr);
+    if (expr) {
+      if (t.isBinary(expr)) expr = t.parenthesizedExpression(expr);
+      nodes.push(expr);
+    }
   });
 
   if (nodes.length > 1) {

lib/6to5/types/visitor-keys.json

@@ -41,6 +41,7 @@
   "NewExpression":            ["callee", "arguments"],
   "ObjectExpression":         ["properties"],
   "ObjectPattern":            ["properties"],
+  "ParenthesizedExpression":  ["expression"],
   "Program":                  ["body"],
   "Property":                 ["key", "value"],
   "ReturnStatement":          ["argument"],

lib/6to5/util.js

@@ -1,3 +1,5 @@
+require("./patch");
+
 var estraverse = require("estraverse");
 var traverse   = require("./traverse");
 var acorn      = require("acorn-6to5");
@@ -7,8 +9,6 @@ var fs         = require("fs");
 var t          = require("./types");
 var _          = require("lodash");
 
-_.extend(estraverse.VisitorKeys, t.VISITOR_KEYS);
-
 exports.inherits = util.inherits;
 
 exports.resolve = function (loc) {
@@ -136,6 +136,8 @@ exports.template = function (name, nodes, keepExpression) {
 
   if (!keepExpression && t.isExpressionStatement(node)) {
     node = node.expression;
+
+    if (t.isParenthesizedExpression(node)) node = node.expression;
   }
 
   if (inherits) {
@@ -190,23 +192,24 @@ exports.parse = function (opts, code, callback) {
     var tokens   = [];
 
     var ast = acorn.parse(code, {
-      ecmaVersion: Infinity,
-      strictMode:  true,
-      onComment:   comments,
-      locations:   true,
-      onToken:     tokens,
-      ranges:      true
+      preserveParens: true,
+      ecmaVersion:    Infinity,
+      strictMode:     true,
+      onComment:      comments,
+      locations:      true,
+      onToken:        tokens,
+      ranges:         true
     });
 
     estraverse.attachComments(ast, comments, tokens);
 
     ast = {
-      type: "File",
-      program: ast
-    };
+      type:    "File",
+      program: ast,
 
-    ast.comments = comments;
-    ast.tokens   = tokens;
+      comments: comments,
+      tokens:   tokens,
+    };
 
     if (callback) {
       return callback(ast);
@@ -238,36 +241,36 @@ exports.parseNoProperties = function (loc, code) {
 };
 
 var loadTemplates = function () {
-  try {
-    return require("../../templates.json");
-  } catch (err) {
-    if (err.code !== "MODULE_NOT_FOUND") throw err;
+  var templates = {};
 
-    var templates = {};
-
-    var templatesLoc = __dirname + "/templates";
-    if (!fs.existsSync(templatesLoc)) {
-      throw new Error("no templates directory - this is most likely the " +
-                      "result of a broken `npm publish`. Please report to " +
-                      "https://githut.com/sebmck/6to5/issues");
-    }
-
-    _.each(fs.readdirSync(templatesLoc), function (name) {
-      if (name[0] === ".") return;
-
-      var key  = path.basename(name, path.extname(name));
-      var loc  = templatesLoc + "/" + name;
-      var code = fs.readFileSync(loc, "utf8");
-
-      templates[key] = exports.parseNoProperties(loc, code);
-    });
-
-    return templates;
+  var templatesLoc = __dirname + "/templates";
+  if (!fs.existsSync(templatesLoc)) {
+    throw new Error("no templates directory - this is most likely the " +
+                    "result of a broken `npm publish`. Please report to " +
+                    "https://githut.com/sebmck/6to5/issues");
   }
+
+  _.each(fs.readdirSync(templatesLoc), function (name) {
+    if (name[0] === ".") return;
+
+    var key  = path.basename(name, path.extname(name));
+    var loc  = templatesLoc + "/" + name;
+    var code = fs.readFileSync(loc, "utf8");
+
+    templates[key] = exports.parseNoProperties(loc, code);
+  });
+
+  return templates;
 };
 
-Object.defineProperty(exports, "templates", {
-  get: function () {
-    return exports.templates = loadTemplates();
-  }
-});
+try {
+  return require("../../templates.json");
+} catch (err) {
+  if (err.code !== "MODULE_NOT_FOUND") throw err;
+
+  Object.defineProperty(exports, "templates", {
+    get: function () {
+      return exports.templates = loadTemplates();
+    }
+  });
+}