feat: make stepper bubbles collapse and refine css working

proposals/utils/stepper.py

@@ -36,6 +36,9 @@ def __init__(
         # which item is current
         self.request = request
         self.items = []
+        self.current_item = None
+        self.current_item_parent = None
+
         self.check_all(self.starting_checkers)
 
     def get_context_data(self):
@@ -84,8 +87,17 @@ def build_stepper(
             raise RuntimeError(
                 "Base layout was never defined for this stepper",
             )
-        # First, insert all items into the layout
+        # First, insert all items into the layout & let them figure out their 
+        #own styling
         for item in self.items:
+            #Only check item.is_current until there is a current item found
+            while not self.current_item:
+                if item.is_current(self.request):
+                    self.current_item = item
+                    self.current_item_ancestor = item.get_ancestor()
+                else:
+                    break
+            item.get_css_classes()
             self._insert_item(layout, item)
         # Second, replace all remaining empty slots in the layout
         # by PlaceholderItems
@@ -96,12 +108,18 @@ def _insert_item(self, layout, new_item):
         """
         Inserts a stepper item into a layout, in-place.
         """
-        # We're only concerned with top-level items, children can sort
-        # themselves out
-        if new_item.parent:
-            return new_item.parent.children.append(
-                new_item,
-            )
+        if not self.current_item:
+            # We're only concerned with top-level items, children can sort
+            # themselves out
+            if new_item.parent:
+                return new_item.parent.children.append(
+                    new_item,
+                )
+        elif new_item.get_ancestor() == self.current_item_ancestor:
+            if new_item.parent:
+                return new_item.parent.children.append(
+                    new_item,
+                )
         # Step through the layout looking for empty slots, which are
         # represented by tuples of locations and titles
         for index, slot in enumerate(layout):
@@ -120,6 +138,8 @@ def _insert_placeholders(self, layout):
         for index, slot in enumerate(layout):
             # Skip slots that are already items
             if isinstance(slot, StepperItem):
+                if slot != self.current_item_ancestor:
+                    slot.children = []
                 continue
             # Remaining empty slots are replaced by placeholders
             placeholder = PlaceholderItem(

proposals/utils/stepper_helpers.py

@@ -50,6 +50,7 @@ def __init__(self, stepper, parent=None, title=None, location=None):
         self.children = []
         self.parent = parent
         self.available = False
+        self.css_classes = ""
         # Don't override default location if not provided explicitly
         if location:
             self.location = location
@@ -70,30 +71,48 @@ def get_url(self):
 
     def get_errors(self):
         return []
-
-    def css_classes(
-        self,
-    ):
-        classes = []
-        if self.is_current(self.stepper.request):
-            classes.append(
-                "active",
-            )
-        return " ".join(classes)
+
+    def get_ancestor(self):
+        """
+        Returns the top level parent, or ancestor
+        """
+        ancestor = self
+        while ancestor.parent:
+            ancestor = ancestor.parent
+        return ancestor
+
+    def get_family(self):
+        """
+        Returns all items with the same ancestor
+        """
+        family = []
+        if not self.parent:
+            return family
+
 
     def is_current(self, request):
         """
         Returns True if this item represents the page the user
-        is currently on.
+        is currently on and appends the active class to the item's
+        css_classes attribute. This gets called when building the stepper,
+        until is_current returns True.
         """
         if request.path == self.get_url():
+            self.css_classes += "active "
             return True
         return False
 
     def is_disabled(self):
         if not self.get_url():
             return True
         return False
+
+    def get_css_classes(self):
+        """
+        A method to be overwritten by child classes to append to an item's
+        self.css_classes attribute. This gets called when building the stepper.
+        """
+        pass
 
 
 class PlaceholderItem(StepperItem):
@@ -129,16 +148,14 @@ def is_current(self, request):
         """
         return False
 
-    def css_classes(self):
-        css_classes = super().css_classes()
+    def get_css_classes(self):
         child_errors = []
         for child in self.children:
             child_errors += child.get_errors()
         if child_errors != []:
-            css_classes += "incomplete"
+            self.css_classes += "incomplete"
         else:
-            css_classes += " complete"
-        return css_classes
+            self.css_classes += " complete"
 
 
 class ModelFormChecker(
@@ -261,14 +278,11 @@ def get_errors(self):
             return self.get_checker_errors() or self.model_form.errors
         return self.model_form.errors
 
-    def css_classes(self):
-        css_classes = super().css_classes()
-
+    def get_css_classes(self):
         if self.get_errors():
-            css_classes += " incomplete"
+            self.css_classes += " incomplete"
         else:
-            css_classes += " complete"
-        return css_classes
+            self.css_classes += " complete"
 
 
 class UpdateOrCreateChecker(