Merge pull request #3061 from HyphaApp/fix/groups-page-issue

Fix permission view for wagtail user groups

hypha/core/wagtail/admin/options.py

+from django.contrib.auth.models import Permission
 from django.core.exceptions import ImproperlyConfigured
+from wagtail.contrib.modeladmin.helpers import PagePermissionHelper, PermissionHelper
 from wagtail.contrib.modeladmin.options import WagtailRegisterable
 from wagtail.contrib.settings.models import BaseSetting
 from wagtail.contrib.settings.registry import SettingMenuItem
+from wagtail.models import Page
 
 
 class SettingModelAdmin(WagtailRegisterable):
@@ -15,6 +18,8 @@ class SettingModelAdmin(WagtailRegisterable):
     """
 
     model = None
+    inspect_view_enabled = False
+    permission_helper_class = None
 
     def __init__(self, parent=None):
         """
@@ -27,8 +32,40 @@ class SettingModelAdmin(WagtailRegisterable):
             )
         self.parent = parent
 
+        self.is_pagemodel = issubclass(self.model, Page)
+        self.permission_helper = self.get_permission_helper_class()(
+            self.model, self.inspect_view_enabled
+        )
+
     def get_menu_item(self, order=None):
         return SettingMenuItem(self.model)
 
     def get_admin_urls_for_registration(self):
         return ()
+
+    def get_permission_helper_class(self):
+        """
+        Returns a permission_helper class to help with permission-based logic
+        for the given model.
+
+        **Copied from the wagtail's ModelAdmin**
+        """
+        if self.permission_helper_class:
+            return self.permission_helper_class
+        if self.is_pagemodel:
+            return PagePermissionHelper
+        return PermissionHelper
+
+    def get_permissions_for_registration(self):
+        """
+        Utilised by Wagtail's 'register_permissions' hook to allow permissions
+        for a model to be assigned to groups in settings. This is only required
+        if the model isn't a Page model, and isn't registered as a Snippet
+
+        **Copied from the wagtail's ModelAdmin**
+        """
+        from wagtail.snippets.models import SNIPPET_MODELS
+
+        if not self.is_pagemodel and self.model not in SNIPPET_MODELS:
+            return self.permission_helper.get_all_model_permissions()
+        return Permission.objects.none()