Add acceptance test of the Graphical Slider Tool [LMS-1641]

lms/djangoapps/courseware/features/gst.feature

+@shard_2
+Feature: LMS.Graphical Slider Tool Module
+  As a student, I want to view a Graphical Slider Tool Component
+
+  Scenario: The slider changes values on the page
+    Given that I have a course with a Graphical Slider Tool
+    When I view the Graphical Slider Tool
+    Then the displayed value should be 0
+    And I move the slider to the right
+    Then the displayed value should be 10
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lms/djangoapps/courseware/features/gst.py

+
+from lettuce import world, steps
+from nose.tools import assert_in, assert_equals, assert_true
+
+from common import i_am_registered_for_the_course, visit_scenario_item
+from problems_setup import add_problem_to_course, answer_problem
+
+
+DEFAULT_DATA = """\
+<render>
+    <p>Test of the graphical slider tool</p>
+    <div class='gst-value'>
+        <span id="value-display" style="width:50px; float:left; margin-left:10px;"/>
+    </div>
+    <div class='gst-input'>
+        <slider var="a" style="width:400px;float:left;margin-left:10px;"/>
+    </div>
+</render>
+<configuration>
+    <parameters>
+        <param var="a" min="0" max="10" step="1" initial="0"/>
+    </parameters>
+    <functions>
+        <function output="element" el_id="value-display">a</function>
+    </functions>
+</configuration>
+"""
+
+@steps
+class GraphicalSliderToolSteps(object):
+    COURSE_NUM = 'test_course'
+
+    def setup_gst(self, step):
+        r'that I have a course with a Graphical Slider Tool$'
+
+        i_am_registered_for_the_course(step, self.COURSE_NUM)
+
+        world.scenario_dict['GST'] = world.ItemFactory(
+            parent_location=world.scenario_dict['SECTION'].location,
+            category='graphical_slider_tool',
+            display_name="Test GST",
+            data=DEFAULT_DATA
+        )
+
+    def view_gst(self, step):
+        r'I view the Graphical Slider Tool$'
+        visit_scenario_item('GST')
+        world.wait_for_js_variable_truthy('$(".xblock-student_view[data-type=GraphicalSliderTool]").data("initialized")')
+        world.wait_for_ajax_complete()
+
+    def check_value(self, step, value):
+        r'the displayed value should be (?P<value>\d+)$'
+
+        assert_equals(world.css_text('.gst-value'), value)
+
+    def move_slider(self, step):
+        r'I move the slider to the right$'
+
+        handle_selector = '.gst-input .ui-slider-handle'
+        world.wait_for_visible(handle_selector)
+        world.wait_for_visible('.gst-value #value-display')
+
+        def try_move():
+            handle = world.css_find(handle_selector).first
+            slider = world.css_find('.gst-input .ui-slider').first
+            (handle.action_chains
+                .click_and_hold(handle._element)
+                .move_by_offset(
+                    int(handle._element.location['x'] + 400),
+                    0
+                ).release().perform())
+
+        world.retry_on_exception(try_move)
+
+
+GraphicalSliderToolSteps()
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