nicen up util methods

lib/6to5/util.js

@@ -4,30 +4,37 @@ var esprima    = require("esprima");
 var path       = require("path");
 var fs         = require("fs");
 var _          = require("lodash");
+var b          = require("ast-types").builders;
 
 _.each(esprima.Syntax, function (name) {
   estraverse.VisitorKeys[name] = estraverse.VisitorKeys[name] || [];
 });
 
-exports.parse = function (code, opts) {
-  opts = _.defaults(opts || {}, {
-    comment: true,
-    tokens:  true,
-    range:   true,
-    loc:     true
-  });
-
-  code = [].concat(code).join("");
+exports.parse = function (filename, code, callback, opts) {
+  opts = opts || {};
+  if (opts === true) {
+    opts =  {
+      comment: true,
+      tokens:  true,
+      range:   true,
+      loc:     true
+    };
+  }
 
   try {
-    var tree = esprima.parse(code, opts);
+    var ast = esprima.parse(code, opts);
 
-    if (tree.tokens && tree.comments) {
-      estraverse.attachComments(tree, tree.comments, tree.tokens);
+    if (ast.tokens && ast.comments) {
+      estraverse.attachComments(ast, ast.comments, ast.tokens);
     }
 
-    return tree;
+    if (callback) {
+      return callback(ast);
+    } else {
+      return ast;
+    }
   } catch (err) {
+    err.message = filename + ": " + err.message;
     if (err.lineNumber) {
       var frame = exports.codeFrame(code, err.lineNumber, err.column);
       err.message = err.message + frame;
@@ -37,14 +44,18 @@ exports.parse = function (code, opts) {
 };
 
 exports.errorWithNode = function (node, msg) {
-  var err = new SyntaxError(msg);
-  err.lineNumber = node.loc.start.line;
-  err.column = node.loc.start.column;
+  var line = node.loc.start.line;
+  var col  = node.loc.start.column;
+
+  var err = new SyntaxError("Line " + line + ": " + msg);
+  err.lineNumber = line;
+  err.column = col;
   return err;
 };
 
 exports.canCompile = function (filename) {
-  return path.extname(filename) === ".js";
+  var ext = path.extname(filename);
+  return ext === ".js" || ext === ".es6";
 };
 
 exports.buildUidGenerator = function () {
@@ -76,38 +87,16 @@ exports.pushMutatorMap = function (mutatorMap, key, kind, method) {
 };
 
 exports.buildDefineProperties = function (mutatorMap, keyNode) {
-  var objExpr = {
-    type: "ObjectExpression",
-    properties: []
-  };
+  var objExpr = b.objectExpression([]);
 
   _.each(mutatorMap, function (map, key) {
-    var mapNode = {
-      type: "ObjectExpression",
-      properties: []
-    };
+    var mapNode = b.objectExpression([]);
 
-    var propNode = {
-      type: "Property",
-      key: {
-        type: "Identifier",
-        name: key
-      },
-      value: mapNode,
-      kind: "init"
-    };
+    var propNode = b.property("init", b.identifier(key), mapNode);
 
     _.each(map, function (methodNode, type) {
       if (methodNode.type === "MethodDefinition") methodNode = methodNode.value;
-      mapNode.properties.push({
-        type: "Property",
-        key: {
-          type: "Identifier",
-          name: type
-        },
-        value: methodNode,
-        kind: "init"
-      });
+      mapNode.properties.push(b.property("init", b.identifier(type), methodNode));
     });
 
     objExpr.properties.push(propNode);
@@ -197,14 +186,12 @@ if (fs.existsSync(templatesCacheLoc)) {
   var templatesLoc = __dirname + "/templates";
 
   _.each(fs.readdirSync(templatesLoc), function (name) {
-    var key = path.basename(name, path.extname(name));
+    var key  = path.basename(name, path.extname(name));
+    var loc  = templatesLoc + "/" + name;
+    var code = fs.readFileSync(loc, "utf8");
 
-    var code = fs.readFileSync(templatesLoc + "/" + name, "utf8");
-    exports.templates[key] = exports.parse(code, {
-      comment: false,
-      tokens:  false,
-      range:   false,
-      loc:     false
-    });
+    var template = exports.parse(loc, code);
+    exports.removeLoc(template);
+    exports.templates[key] = template;
   });
 }