Add Unit & Nested blocks to breadcrumbs

hide links that has no url

Hide sequence nav in nested pages

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cms/djangoapps/contentstore/views/component.py

@@ -122,10 +122,36 @@ def container_handler(request, usage_key_string):
 
             component_templates = get_component_templates(course)
             ancestor_xblocks = []
+            parent = get_parent_xblock(xblock)
             action = request.GET.get('action', 'view')
 
             is_unit_page = is_unit(xblock)
-            unit = xblock if is_unit_page else get_parent_xblock(xblock)
+            unit = xblock if is_unit_page else None
+
+            is_first = True
+            block = xblock
+
+            # Build the breadcrumbs and find the ``Unit`` ancestor
+            # if it is not the immediate parent.
+            while parent:
+
+                if unit is None and is_unit(block):
+                    unit = block
+
+                # add all to nav except current xblock page
+                if xblock != block:
+                    current_block = {
+                        'title': block.display_name_with_default,
+                        'children': parent.get_children(),
+                        'is_last': is_first
+                    }
+                    is_first = False
+                    ancestor_xblocks.append(current_block)
+
+                block = parent
+                parent = get_parent_xblock(parent)
+
+            ancestor_xblocks.reverse()
 
             assert unit is not None, "Could not determine unit page"
             subsection = get_parent_xblock(unit)
@@ -134,15 +160,6 @@ def container_handler(request, usage_key_string):
             section = get_parent_xblock(subsection)
             assert section is not None, "Could not determine ancestor section from unit " + six.text_type(unit.location)
 
-            # build the breadcrumbs
-            for block in (section, subsection):
-                parent = get_parent_xblock(block)
-                ancestor_xblocks.append({
-                    'title': block.display_name_with_default,
-                    'children': parent.get_children(),
-                    'is_last': block.category == 'sequential'
-                })
-
             # for the sequence navigator
             prev_url, next_url = get_sibling_urls(subsection)
             # these are quoted here because they'll end up in a query string on the page,