fix: _remove_element failing silently when child objects left over

Author: iisakkirotko

reacton/core.py

@@ -1476,7 +1476,7 @@ def format(reason: RerenderReason):
                         for el in self._shared_elements_next:
                             logger.debug("\t%r %x", el, id(el))
 
-                        logger.debug("Current elements:")
+                        logger.debug("Current elements: %r", self._shared_elements)
                         for el in self._shared_elements:
                             logger.debug("\t %r %x", el, id(el))
                         if self.context_root.exceptions_children:
@@ -1564,7 +1564,10 @@ def format(reason: RerenderReason):
 
                     value = html.escape(error)
                 from . import ipywidgets as w
+                from pprint import pprint
 
+                print("EXCEPTION FROM REACTON", value, "\n")
+                pprint(self.container)
                 return self.render(w.HTML(value="<pre>" + value + "</pre>", layout=w.Layout(overflow="auto")), self.container)
             else:
                 raise exc
@@ -2129,6 +2132,17 @@ def _remove_element(self, el: Element, default_key: str, parent_key):
                 new_parent_key = join_key(parent_key, key)
                 self._remove_element(self.context.root_element, "/", parent_key=new_parent_key)
             finally:
+                try:
+                    assert not child_context.elements, f"left over elements {child_context.elements}"
+                    assert not child_context.element_to_widget, f"left over element_to_widget {child_context.element_to_widget}"
+                    assert not child_context.widgets, f"left over widgets {child_context.widgets}"
+                    assert not child_context.children, f"left over children {child_context.children}"
+                    assert not child_context.owns, f"left over owns {child_context.owns}"
+                    # TODO: this is not the case when an exception occurs
+                    # assert not child_context.children_next, f"left over children {child_context.children_next}"
+                except Exception as e:
+                    child_context.exceptions_self.append(e)
+
                 # restore context
                 self.context = context
             if child_context.exceptions_self or child_context.exceptions_children and not child_context.exception_handler:
@@ -2163,14 +2177,6 @@ def _remove_element(self, el: Element, default_key: str, parent_key):
         if el in context.element_to_widget:
             del context.element_to_widget[el]
         del context.elements[key]
-        if isinstance(el.component, ComponentFunction):
-            assert not child_context.elements, f"left over elements {child_context.elements}"
-            assert not child_context.element_to_widget, f"left over element_to_widget {child_context.element_to_widget}"
-            assert not child_context.widgets, f"left over widgets {child_context.widgets}"
-            assert not child_context.children, f"left over children {child_context.children}"
-            assert not child_context.owns, f"left over owns {child_context.owns}"
-            # TODO: this is not the case when an exception occurs
-            # assert not child_context.children_next, f"left over children {child_context.children_next}"
 
     def _visit_children(self, el: Element, default_key: str, parent_key: str, f: Callable):
         assert self.context is not None