small cleanup

lib/ace/mode/javascript_worker.js

@@ -47,7 +47,7 @@ var errorsRe = startRegex([
     "Unexpected",
     "Expected ",
     "Confusing (plus|minus)",
-    "{a} unterminated regular expression",
+    "\\{a\\} unterminated regular expression",
     "Unclosed ",
     "Unmatched ",
     "Unbegun comment",
@@ -61,6 +61,7 @@ var infoRe = startRegex([
     "Unexpected comma",
     "Unexpected space",
     "Missing radix parameter.",
+    "\\['\\{a\\}'\\] is better written in dot notation."
 ]);
 
 var JavaScriptWorker = exports.JavaScriptWorker = function(sender) {
@@ -76,24 +77,40 @@ oop.inherits(JavaScriptWorker, Mirror);
         this.options = options || {
             // undef: true,
             // unused: true,
+            es5: true,
+            esnext: true,
             devel: true,
             browser: true,
             node: true,
             laxcomma: true,
             laxbreak: true,
+            lastsemic: true,
             onevar: false,
             passfail: false,
             maxerr: 100,
-            expr: true
+            expr: true,
+            multistr: true,
+            globalstrict: true
         };
         this.doc.getValue() && this.deferredUpdate.schedule(100);
     };
-    
+
     this.changeOptions = function(newOptions) {
         oop.mixin(this.options, newOptions);
         this.doc.getValue() && this.deferredUpdate.schedule(100);
     };
 
+    this.isValidJS = function(str) {
+        try {
+            // evaluated code can only create variables in this function
+            eval("throw 0;" + str);
+        } catch(e) {
+            if (e === 0)
+                return true;
+        }
+        return false
+    };
+
     this.onUpdate = function() {
         var value = this.doc.getValue();
         value = value.replace(/^#!.*\n/, "\n");
@@ -105,14 +122,7 @@ oop.inherits(JavaScriptWorker, Mirror);
 
         // jshint reports many false errors
         // report them as error only if code is actually invalid
-        var maxErrorLevel = "warning";
-        try {
-            eval("throw 0;" + value);
-        } catch(e) {
-            if (e != 0) {
-                maxErrorLevel = "error";
-            }
-        }
+        var maxErrorLevel = this.isValidJS(value) ? "warning" : "error";
 
         // var start = new Date();
         lint(value, this.options);
@@ -129,7 +139,7 @@ oop.inherits(JavaScriptWorker, Mirror);
             if (raw == "Missing semicolon.") {
                 var str = error.evidence.substr(error.character);
                 str = str.charAt(str.search(/\S/));
-                if (maxErrorLevel == "error" && str && /[\w\d{([]/.test(str)) {
+                if (maxErrorLevel == "error" && str && /[\w\d{(['"]/.test(str)) {
                     error.reason = 'Missing ";" before statement';
                     type = "error";
                 } else