From c0f0ef0cd2fea7dcd18aa7a150f143d17207a4cd Mon Sep 17 00:00:00 2001
From: cahrens <christina@edx.org>
Date: Wed, 27 Feb 2013 17:34:08 -0500
Subject: [PATCH] Bug fix for #214.

https://edx.lighthouseapp.com/projects/102637-studio/tickets/214-Via-Tender-Numerical-Input-answer-0-a-tolerance-is-not-accepted#ticket-214-4
---
 .../xmodule/js/spec/problem/edit_spec.coffee  | 20 ++++++++++++++++---
 .../xmodule/js/src/problem/edit.coffee        |  9 +++++----
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/common/lib/xmodule/xmodule/js/spec/problem/edit_spec.coffee b/common/lib/xmodule/xmodule/js/spec/problem/edit_spec.coffee
index 9b8062d60d..cf7d6bef94 100644
--- a/common/lib/xmodule/xmodule/js/spec/problem/edit_spec.coffee
+++ b/common/lib/xmodule/xmodule/js/spec/problem/edit_spec.coffee
@@ -119,13 +119,13 @@ describe 'MarkdownEditingDescriptor', ->
         <p>The answer is correct if it is within a specified numerical tolerance of the expected answer.</p>
         
         <p>Enter the numerical value of Pi:</p>
-        <numericalresponse answer="3.14159 ">
+        <numericalresponse answer="3.14159">
           <responseparam type="tolerance" default=".02" />
           <textline />
         </numericalresponse>
         
         <p>Enter the approximate value of 502*9:</p>
-        <numericalresponse answer="4518 ">
+        <numericalresponse answer="4518">
           <responseparam type="tolerance" default="15%" />
           <textline />
         </numericalresponse>
@@ -147,6 +147,20 @@ describe 'MarkdownEditingDescriptor', ->
 
         </div>
         </solution>
+        </problem>""")
+    it 'will convert 0 as a numerical response (instead of string response)', ->
+      data =  MarkdownEditingDescriptor.markdownToXml("""
+        Enter 0 with a tolerance:
+        = 0 +- .02
+        """)
+      expect(data).toEqual("""<problem>
+        <p>Enter 0 with a tolerance:</p>
+        <numericalresponse answer="0">
+          <responseparam type="tolerance" default=".02" />
+          <textline />
+        </numericalresponse>
+
+
         </problem>""")
     it 'converts multiple choice to xml', ->
       data = MarkdownEditingDescriptor.markdownToXml("""A multiple choice problem presents radio buttons for student input. Students can only select a single option presented. Multiple Choice questions have been the subject of many areas of research due to the early invention and adoption of bubble sheets.
@@ -369,4 +383,4 @@ describe 'MarkdownEditingDescriptor', ->
         <p>bad tests require drivel</p>
         </div>
         </problem>""")
-    # failure tests
+    # failure tests here
diff --git a/common/lib/xmodule/xmodule/js/src/problem/edit.coffee b/common/lib/xmodule/xmodule/js/src/problem/edit.coffee
index 2bfe483a7f..b723f230e9 100644
--- a/common/lib/xmodule/xmodule/js/src/problem/edit.coffee
+++ b/common/lib/xmodule/xmodule/js/src/problem/edit.coffee
@@ -231,13 +231,14 @@ class @MarkdownEditingDescriptor extends XModule.Descriptor
       // replace string and numerical
       xml = xml.replace(/^\=\s*(.*?$)/gm, function(match, p) {
         var string;
-        var params = /(.*?)\+\-\s*(.*?$)/.exec(p);
-        if(parseFloat(p)) {
+        var floatValue = parseFloat(p);
+        if(!isNaN(floatValue)) {
+          var params = /(.*?)\+\-\s*(.*?$)/.exec(p);
           if(params) {
-            string = '<numericalresponse answer="' + params[1] + '">\n';
+            string = '<numericalresponse answer="' + floatValue + '">\n';
             string += '  <responseparam type="tolerance" default="' + params[2] + '" />\n';
           } else {
-            string = '<numericalresponse answer="' + p + '">\n';
+            string = '<numericalresponse answer="' + floatValue + '">\n';
           }
           string += '  <textline />\n';
           string += '</numericalresponse>\n\n';