Addressed review notes:

* Added tests for `problem_types` CapaDescriptor property
* Improved indentation in tests
* Improved validation messages

common/lib/capa/capa/responsetypes.py

@@ -441,7 +441,7 @@ class JavascriptResponse(LoncapaResponse):
     Javascript using Node.js.
     """
 
-    human_name = _('Javascript Input')
+    human_name = _('JavaScript Input')
     tags = ['javascriptresponse']
     max_inputfields = 1
     allowed_inputfields = ['javascriptinput']

common/lib/xmodule/xmodule/library_content_module.py

@@ -6,6 +6,7 @@ from bson.objectid import ObjectId, InvalidId
 from collections import namedtuple
 from copy import copy
 from capa.responsetypes import registry
+from gettext import ngettext
 
 from .mako_module import MakoModuleDescriptor
 from opaque_keys import InvalidKeyError
@@ -359,7 +360,8 @@ class LibraryContentDescriptor(LibraryContentFields, MakoModuleDescriptor, XmlDe
                         # TODO: change this to action_runtime_event='...' once the unit page supports that feature.
                         # See https://openedx.atlassian.net/browse/TNL-993
                         action_class='library-update-btn',
-                        action_label=_(u"↻ Update now")
+                        # Translators: ↻ is an UTF icon symbol, no need translating it.
+                        action_label=_(u"↻ Update now.")
                     )
                 )
                 return False
@@ -369,7 +371,7 @@ class LibraryContentDescriptor(LibraryContentFields, MakoModuleDescriptor, XmlDe
                     StudioValidationMessage.ERROR,
                     _(u'Library is invalid, corrupt, or has been deleted.'),
                     action_class='edit-button',
-                    action_label=_(u"Edit Library List")
+                    action_label=_(u"Edit Library List.")
                 )
             )
             return False
@@ -395,7 +397,7 @@ class LibraryContentDescriptor(LibraryContentFields, MakoModuleDescriptor, XmlDe
                     StudioValidationMessage.NOT_CONFIGURED,
                     _(u"A library has not yet been selected."),
                     action_class='edit-button',
-                    action_label=_(u"Select a Library")
+                    action_label=_(u"Select a Library.")
                 )
             )
             return validation
@@ -418,7 +420,7 @@ class LibraryContentDescriptor(LibraryContentFields, MakoModuleDescriptor, XmlDe
                     StudioValidationMessage.WARNING,
                     _(u'There are no matching problem types in the specified libraries.'),
                     action_class='edit-button',
-                    action_label=_(u"Select another problem type")
+                    action_label=_(u"Select another problem type.")
                 )
             )
 
@@ -427,11 +429,20 @@ class LibraryContentDescriptor(LibraryContentFields, MakoModuleDescriptor, XmlDe
                 validation,
                 StudioValidationMessage(
                     StudioValidationMessage.WARNING,
-                    _(u'The specified libraries are configured to fetch {count} problems, '
-                      u'but there are only {actual} matching problems.')
-                    .format(actual=matching_children_count, count=self.max_count),
+                    (
+                        ngettext(
+                            u'The specified libraries are configured to fetch {count} problem, ',
+                            u'The specified libraries are configured to fetch {count} problems, ',
+                            self.max_count
+                        ) +
+                        ngettext(
+                            u'but there are only {actual} matching problem.',
+                            u'but there are only {actual} matching problems.',
+                            matching_children_count
+                        )
+                    ).format(count=self.max_count, actual=matching_children_count),
                     action_class='edit-button',
-                    action_label=_(u"Edit configuration")
+                    action_label=_(u"Edit the library configuration.")
                 )
             )
 

common/lib/xmodule/xmodule/tests/test_capa_module.py

@@ -19,10 +19,11 @@ from webob.multidict import MultiDict
 
 import xmodule
 from xmodule.tests import DATA_DIR
+from capa import responsetypes
 from capa.responsetypes import (StudentInputError, LoncapaProblemError,
                                 ResponseError)
 from capa.xqueue_interface import XQueueInterface
-from xmodule.capa_module import CapaModule, ComplexEncoder
+from xmodule.capa_module import CapaModule, CapaDescriptor, ComplexEncoder
 from opaque_keys.edx.locations import Location
 from xblock.field_data import DictFieldData
 from xblock.fields import ScopeIds
@@ -1660,6 +1661,62 @@ class CapaModuleTest(unittest.TestCase):
                               ('answerpool', ['choice_1', 'choice_3', 'choice_2', 'choice_0']))
             self.assertEquals(event_info['success'], 'incorrect')
 
+@ddt.ddt
+class CapaDescriptorTest(unittest.TestCase):
+    def _create_descriptor(self, xml):
+        """ Creates a CapaDescriptor to run test against """
+        descriptor = CapaDescriptor(get_test_system(), scope_ids=1)
+        descriptor.data = xml
+        return descriptor
+
+    @ddt.data(*responsetypes.registry.registered_tags())
+    def test_all_response_types(self, response_tag):
+        """ Tests that every registered response tag is correctly returned """
+        xml = "<problem><{response_tag}></{response_tag}></problem>".format(response_tag=response_tag)
+        descriptor = self._create_descriptor(xml)
+        self.assertEquals(descriptor.problem_types, {response_tag})
+
+    def test_response_types_ignores_non_response_tags(self):
+        xml = textwrap.dedent("""
+            <problem>
+            <p>Label</p>
+            <div>Some comment</div>
+            <multiplechoiceresponse>
+              <choicegroup type="MultipleChoice" answer-pool="4">
+                <choice correct="false">Apple</choice>
+                <choice correct="false">Banana</choice>
+                <choice correct="false">Chocolate</choice>
+                <choice correct ="true">Donut</choice>
+              </choicegroup>
+            </multiplechoiceresponse>
+            </problem>
+        """)
+        descriptor = self._create_descriptor(xml)
+        self.assertEquals(descriptor.problem_types, {"multiplechoiceresponse"})
+
+    def test_response_types_multiple_tags(self):
+        xml = textwrap.dedent("""
+            <problem>
+                <p>Label</p>
+                <div>Some comment</div>
+                <multiplechoiceresponse>
+                  <choicegroup type="MultipleChoice" answer-pool="1">
+                    <choice correct ="true">Donut</choice>
+                  </choicegroup>
+                </multiplechoiceresponse>
+                <multiplechoiceresponse>
+                  <choicegroup type="MultipleChoice" answer-pool="1">
+                    <choice correct ="true">Buggy</choice>
+                  </choicegroup>
+                </multiplechoiceresponse>
+                <optionresponse>
+                    <optioninput label="Option" options="('1','2')" correct="2"></optioninput>
+                </optionresponse>
+            </problem>
+        """)
+        descriptor = self._create_descriptor(xml)
+        self.assertEquals(descriptor.problem_types, {"multiplechoiceresponse", "optionresponse"})
+
 
 class ComplexEncoderTest(unittest.TestCase):
     def test_default(self):
@@ -1690,18 +1747,10 @@ class TestProblemCheckTracking(unittest.TestCase):
               <p>Which piece of furniture is built for sitting?</p>
               <multiplechoiceresponse>
                 <choicegroup type="MultipleChoice">
-                  <choice correct="false">
-                    <text>a table</text>
-                  </choice>
-                  <choice correct="false">
-                    <text>a desk</text>
-                  </choice>
-                  <choice correct="true">
-                    <text>a chair</text>
-                  </choice>
-                  <choice correct="false">
-                    <text>a bookshelf</text>
-                  </choice>
+                  <choice correct="false"><text>a table</text></choice>
+                  <choice correct="false"><text>a desk</text></choice>
+                  <choice correct="true"><text>a chair</text></choice>
+                  <choice correct="false"><text>a bookshelf</text></choice>
                 </choicegroup>
               </multiplechoiceresponse>
               <p>Which of the following are musical instruments?</p>

common/test/acceptance/tests/lms/test_library.py

@@ -293,7 +293,7 @@ class StudioLibraryContainerCapaFilterTest(LibraryContentTestBase):
         # Choice group test
         children_headers = self._set_library_content_settings(count=2, capa_type="Dropdown")
         self.assertEqual(len(children_headers), 2)
-        self.assertLessEqual(
+        self.assertEqual(
             children_headers,
             set([header.upper() for header in ["Problem Select 1", "Problem Select 2"]])
         )

common/test/acceptance/tests/studio/test_studio_library_container.py

 """
 Acceptance tests for Library Content in LMS
 """
+import textwrap
 import ddt
 from .base_studio_test import StudioLibraryTest
 from ...fixtures.course import CourseFixture
@@ -45,11 +46,13 @@ class StudioLibraryContainerTest(StudioLibraryTest, UniqueCourseTest):
 
             XBlockFixtureDesc(
                 "problem", "Dropdown",
-                data="""
-<problem>
-    <p>Dropdown</p>
-    <optionresponse><optioninput label="Dropdown" options="('1', '2')" correct="'2'"></optioninput></optionresponse>
-</problem>""")
+                data=textwrap.dedent("""
+                    <problem>
+                        <p>Dropdown</p>
+                        <optionresponse><optioninput label="Dropdown" options="('1', '2')" correct="'2'"></optioninput></optionresponse>
+                    </problem>
+                    """)
+            )
         )
 
     def populate_course_fixture(self, course_fixture):