BLD-474: Allow multiple answers for string response.

CHANGELOG.rst

@@ -5,6 +5,8 @@ These are notable changes in edx-platform.  This is a rolling list of changes,
 in roughly chronological order, most recent first.  Add your entries at or near
 the top.  Include a label indicating the component affected.
 
+Blades: Allow multiple strings as the correct answer to a string response question. BLD-474.
+
 Blades: a11y - Videos will alert screenreaders when the video is over.
 
 LMS: Trap focus on the loading element when a user loads more threads

cms/templates/widgets/problem-edit.html

@@ -75,7 +75,9 @@
                     <img src="${static.url("img/string-example.png")}" />
                 </div>
                 <div class="col">
-                    <pre><code>= dog</code></pre>
+                    <pre><code>= dog
+or= cat
+or= mouse</code></pre>
                 </div>
             </div>
             <div class="row">

common/lib/capa/capa/responsetypes.py

@@ -946,17 +946,34 @@ class NumericalResponse(LoncapaResponse):
 
 
 class StringResponse(LoncapaResponse):
+    '''
+    This response type allows one or more answers. Use `_or_` separator to set
+    more than 1 answer.
+
+    Example:
+
+        # One answer
+        <stringresponse answer="Michigan">
+          <textline size="20" />
+        </stringresponse >
+
+        # Multiple answers
+        <stringresponse answer="Martin Luther King_or_Dr. Martin Luther King Jr.">
+          <textline size="20" />
+        </stringresponse >
 
+    '''
     response_tag = 'stringresponse'
     hint_tag = 'stringhint'
     allowed_inputfields = ['textline']
     required_attributes = ['answer']
     max_inputfields = 1
-    correct_answer = None
+    correct_answer = []
+    SEPARATOR = '_or_'
 
     def setup_response(self):
-        self.correct_answer = contextualize_text(
-            self.xml.get('answer'), self.context).strip()
+        self.correct_answer = [contextualize_text(answer, self.context).strip()
+            for answer in self.xml.get('answer').split(self.SEPARATOR)]
 
     def get_score(self, student_answers):
         '''Grade a string response '''
@@ -966,23 +983,25 @@ class StringResponse(LoncapaResponse):
 
     def check_string(self, expected, given):
         if self.xml.get('type') == 'ci':
-            return given.lower() == expected.lower()
-        return given == expected
+            return given.lower() in [i.lower() for i in expected]
+        return given in expected
 
     def check_hint_condition(self, hxml_set, student_answers):
         given = student_answers[self.answer_id].strip()
         hints_to_show = []
         for hxml in hxml_set:
             name = hxml.get('name')
-            correct_answer = contextualize_text(
-                hxml.get('answer'), self.context).strip()
+
+            correct_answer = [contextualize_text(answer, self.context).strip()
+            for answer in hxml.get('answer').split(self.SEPARATOR)]
+
             if self.check_string(correct_answer, given):
                 hints_to_show.append(name)
         log.debug('hints_to_show = %s', hints_to_show)
         return hints_to_show
 
     def get_answers(self):
-        return {self.answer_id: self.correct_answer}
+        return {self.answer_id: ' <b>or</b> '.join(self.correct_answer)}
 
 #-----------------------------------------------------------------------------
 

common/lib/capa/capa/tests/test_responsetypes.py

@@ -500,6 +500,7 @@ class StringResponseTest(ResponseTest):
     xml_factory_class = StringResponseXMLFactory
 
     def test_case_sensitive(self):
+        # Test single answer
         problem = self.build_problem(answer="Second", case_sensitive=True)
 
         # Exact string should be correct
@@ -509,7 +510,20 @@ class StringResponseTest(ResponseTest):
         self.assert_grade(problem, "Other String", "incorrect")
         self.assert_grade(problem, "second", "incorrect")
 
+        # Test multiple answers
+        answers = ["Second", "Third", "Fourth"]
+        problem = self.build_problem(answer="_or_".join(answers), case_sensitive=True)
+
+        for answer in answers:
+            # Exact string should be correct
+            self.assert_grade(problem, answer, "correct")
+
+        # Other strings and the lowercase version of the string are incorrect
+        self.assert_grade(problem, "Other String", "incorrect")
+        self.assert_grade(problem, "second", "incorrect")
+
     def test_case_insensitive(self):
+        # Test single answer
         problem = self.build_problem(answer="Second", case_sensitive=False)
 
         # Both versions of the string should be allowed, regardless
@@ -520,9 +534,28 @@ class StringResponseTest(ResponseTest):
         # Other strings are not allowed
         self.assert_grade(problem, "Other String", "incorrect")
 
+        # Test multiple answers
+        answers = ["Second", "Third", "Fourth"]
+        problem = self.build_problem(answer="_or_".join(answers), case_sensitive=False)
+
+        for answer in answers:
+            # Exact string should be correct
+            self.assert_grade(problem, answer, "correct")
+            self.assert_grade(problem, answer.lower(), "correct")
+
+        # Other strings and the lowercase version of the string are incorrect
+        self.assert_grade(problem, "Other String", "incorrect")
+
     def test_hints(self):
+        multiple_answers = [
+            "Martin Luther King Junior",
+            "Doctor Martin Luther King Junior",
+            "Dr. Martin Luther King Jr.",
+            "Martin Luther King"
+        ]
         hints = [("wisconsin", "wisc", "The state capital of Wisconsin is Madison"),
-                 ("minnesota", "minn", "The state capital of Minnesota is St. Paul")]
+                 ("minnesota", "minn", "The state capital of Minnesota is St. Paul"),
+                 ("_or_".join(multiple_answers), "mlk", "He lead the civil right movement in the United States of America.")]
 
         problem = self.build_problem(answer="Michigan",
                                      case_sensitive=False,
@@ -550,6 +583,14 @@ class StringResponseTest(ResponseTest):
         correct_map = problem.grade_answers(input_dict)
         self.assertEquals(correct_map.get_hint('1_2_1'), "")
 
+        # We should get the same hint for each answer
+        for answer in multiple_answers:
+            input_dict = {'1_2_1': answer}
+            correct_map = problem.grade_answers(input_dict)
+            self.assertEquals(correct_map.get_hint('1_2_1'),
+                              "He lead the civil right movement in the United States of America.")
+
+
     def test_computed_hints(self):
         problem = self.build_problem(
             answer="Michigan",

common/lib/xmodule/xmodule/js/src/problem/edit.coffee

@@ -228,11 +228,13 @@ class @MarkdownEditingDescriptor extends XModule.Descriptor
       });
 
       // replace string and numerical
-      xml = xml.replace(/^\=\s*(.*?$)/gm, function(match, p) {
-        var string;
-        var floatValue = parseFloat(p);
+      xml = xml.replace(/(^\=\s*(.*?$)(\n*or\=\s*(.*?$))*)+/gm, function(match, p) {
+        var string,
+            answersList = p.replace(/^(or)?=\s*/gm, '').split('\n'),
+            floatValue = parseFloat(answersList[0]);
+
         if(!isNaN(floatValue)) {
-          var params = /(.*?)\+\-\s*(.*?$)/.exec(p);
+          var params = /(.*?)\+\-\s*(.*?$)/.exec(answersList[0]);
           if(params) {
             string = '<numericalresponse answer="' + floatValue + '">\n';
             string += '  <responseparam type="tolerance" default="' + params[2] + '" />\n';
@@ -242,10 +244,16 @@ class @MarkdownEditingDescriptor extends XModule.Descriptor
           string += '  <formulaequationinput />\n';
           string += '</numericalresponse>\n\n';
         } else {
-          string = '<stringresponse answer="' + p + '" type="ci">\n  <textline size="20"/>\n</stringresponse>\n\n';
+            var answers = [];
+
+            for(var i = 0; i < answersList.length; i++) {
+                answers.push(answersList[i])
+            }
+
+            string = '<stringresponse answer="' + answers.join('_or_') + '" type="ci">\n  <textline size="20"/>\n</stringresponse>\n\n';
         }
         return string;
-      });
+    });
 
       // replace selects
       xml = xml.replace(/\[\[(.+?)\]\]/g, function(match, p) {
@@ -262,13 +270,13 @@ class @MarkdownEditingDescriptor extends XModule.Descriptor
         selectString += '</optionresponse>\n\n';
         return selectString;
       });
-      
+
       // replace explanations
       xml = xml.replace(/\[explanation\]\n?([^\]]*)\[\/?explanation\]/gmi, function(match, p1) {
           var selectString = '<solution>\n<div class="detailed-solution">\nExplanation\n\n' + p1 + '\n</div>\n</solution>';
           return selectString;
       });
-      
+
       // replace code blocks
       xml = xml.replace(/\[code\]\n?([^\]]*)\[\/?code\]/gmi, function(match, p1) {
           var selectString = '<pre><code>\n' + p1 + '</code></pre>';
@@ -293,7 +301,7 @@ class @MarkdownEditingDescriptor extends XModule.Descriptor
 
       // rid white space
       xml = xml.replace(/\n\n\n/g, '\n');
-      
+
       // surround w/ problem tag
       xml = '<problem>\n' + xml + '\n</problem>';