Merge pull request #1843 from MITx/feature/diana/textline-trailing

Add the ability to add trailing text to textlines

common/lib/capa/capa/inputtypes.py

@@ -457,8 +457,21 @@ class TextLine(InputTypeBase):
     """
     A text line input.  Can do math preview if "math"="1" is specified.
 
-    If the hidden attribute is specified, the textline is hidden and the input id is stored in a div with name equal
-    to the value of the hidden attribute.  This is used e.g. for embedding simulations turned into questions.
+    If "trailing_text" is set to a value, then the textline will be shown with 
+    the value after the text input, and before the checkmark or any input-specific 
+    feedback. HTML will not work, but properly escaped HTML characters will. This 
+    feature is useful if you would like to specify a specific type of units for the 
+    text input.
+
+    If the hidden attribute is specified, the textline is hidden and the input id 
+    is stored in a div with name equal to the value of the hidden attribute.  This 
+    is used e.g. for embedding simulations turned into questions.
+
+    Example:
+        <texline math="1" trailing_text="m/s" />
+
+    This example will render out a text line with a math preview and the text 'm/s' 
+    after the end of the text line.
     """
 
     template = "textline.html"
@@ -483,6 +496,7 @@ class TextLine(InputTypeBase):
             Attribute('dojs', None, render=False),
             Attribute('preprocessorClassName', None, render=False),
             Attribute('preprocessorSrc', None, render=False),
+            Attribute('trailing_text', ''),
         ]
 
     def setup(self):

common/lib/capa/capa/templates/textline.html

@@ -31,6 +31,7 @@
             style="display:none;"
         % endif
    />
+   ${trailing_text | h}
 
       <p class="status">
         % if status == 'unsubmitted':

common/lib/capa/capa/tests/test_html_render.py

@@ -156,6 +156,7 @@ class CapaHtmlRenderTest(unittest.TestCase):
                                         'hidden': False,
                                         'do_math': False,
                                         'id': '1_2_1',
+                                        'trailing_text': '',
                                         'size': None}
 
         expected_solution_context = {'id': '1_solution_1'}

common/lib/capa/capa/tests/test_inputtypes.py

@@ -182,6 +182,7 @@ class TextLineTest(unittest.TestCase):
                     'hidden': False,
                     'inline': False,
                     'do_math': False,
+                    'trailing_text': '',
                     'preprocessor': None}
         self.assertEqual(context, expected)
 
@@ -209,11 +210,49 @@ class TextLineTest(unittest.TestCase):
                     'msg': '',
                     'hidden': False,
                     'inline': False,
+                    'trailing_text': '',
                     'do_math': True,
                     'preprocessor': {'class_name': preprocessorClass,
                                      'script_src': script}}
         self.assertEqual(context, expected)
 
+    def test_trailing_text_rendering(self):
+        size = "42"
+        # store (xml_text, expected)
+        trailing_text = []
+        # standard trailing text
+        trailing_text.append(('m/s', 'm/s'))
+        # unicode trailing text
+        trailing_text.append((u'\xc3', u'\xc3'))
+        # html escaped trailing text
+        # this is the only one we expect to change
+        trailing_text.append(('a &lt; b','a < b'))
+
+        for xml_text, expected_text in trailing_text:
+            xml_str = u"""<textline id="prob_1_2" 
+                            size="{size}" 
+                            trailing_text="{tt}"
+                            />""".format(size=size, tt=xml_text)
+
+            element = etree.fromstring(xml_str)
+
+            state = {'value': 'BumbleBee', }
+            the_input = lookup_tag('textline')(test_system, element, state)
+
+            context = the_input._get_render_context()
+
+            expected = {'id': 'prob_1_2',
+                        'value': 'BumbleBee',
+                        'status': 'unanswered',
+                        'size': size,
+                        'msg': '',
+                        'hidden': False,
+                        'inline': False,
+                        'do_math': False,
+                        'trailing_text': expected_text,
+                        'preprocessor': None}
+            self.assertEqual(context, expected)
+
 
 class FileSubmissionTest(unittest.TestCase):
     '''