Fix the "test for nothing was streamed" so it doesn't add empty elements -- but only when there wasn't already something there.

IPython/frontend/html/notebook/static/js/codecell.js

@@ -623,12 +623,8 @@ var IPython = (function (IPython) {
         if (json.stream == undefined){
             json.stream = 'stdout';
         }
+
         var text = utils.fixConsole(json.text);
-        if (!text){
-            // fixConsole gives nothing (empty string, \r, etc.)
-            // so don't append any elements, which might add undesirable space
-            return;
-        }
         var subclass = "output_"+json.stream;
         if (this.outputs.length > 0){
             // have at least one output to consider
@@ -644,6 +640,12 @@ var IPython = (function (IPython) {
             }
         }
 
+        if (!text.replace("\r", "")) {
+            // text is nothing (empty string, \r, etc.)
+            // so don't append any elements, which might add undesirable space
+            return;
+        }
+
         // If we got here, attach a new div
         var toinsert = this.create_output_area();
         this.append_text(text, toinsert, "output_stream "+subclass);

IPython/frontend/html/notebook/static/js/utils.js

@@ -57,7 +57,6 @@ IPython.utils = (function (IPython) {
         var cmds = [];
         var opener = "";
         var closer = "";
-        // \r does nothing, so shouldn't be included
         while (re.test(txt)) {
             var cmds = txt.match(re)[1].split(";");
             closer = opened?"</span>":"";