Implement undo for context and geometry operators. See #1475.

src/ifcopenshell-python/ifcopenshell/file.py

@@ -71,15 +71,19 @@ class Transaction:
         for inverse in self.file.get_inverse(element):
             inverse_references = []
             for i, attribute in enumerate(inverse):
-                if attribute == element:
-                    inverse_references.append((i, "single"))
-                elif isinstance(attribute, tuple) and element in attribute:
-                    inverse_references.append((i, "multiple"))
+                if self.has_element_reference(attribute, element):
+                    inverse_references.append((i, self.serialise_value(inverse, attribute)))
             inverses[inverse.id()] = inverse_references
         self.operations.append(
             {"action": "delete", "inverses": inverses, "value": self.serialise_entity_instance(element)}
         )
 
+    def has_element_reference(self, value, element):
+        if isinstance(value, (tuple, list)):
+            for v in value:
+                return self.has_element_reference(v, element)
+        return value == element
+
     def rollback(self):
         for operation in self.operations[::-1]:
             if operation["action"] == "create":
@@ -105,16 +109,8 @@ class Transaction:
                         pass
                 for inverse_id, data in operation["inverses"].items():
                     inverse = self.file.by_id(inverse_id)
-                    for index, data_type in data:
-                        if data_type == "single":
-                            inverse[index] = e
-                        elif data_type == "multiple":
-                            if inverse[index] is None:
-                                inverse[index] = e
-                            else:
-                                new = list(inverse[index])
-                                new.append(e)
-                                inverse[index] = new
+                    for index, value in data:
+                        inverse[index] = self.unserialise_value(inverse, value)
 
     def commit(self):
         for operation in self.operations:

src/ifcopenshell-python/ifcopenshell/util/element.py

@@ -91,14 +91,19 @@ def get_aggregate(element):
 
 def replace_attribute(element, old, new):
     for i, attribute in enumerate(element):
-        if attribute == old:
-            element[i] = new
-        elif isinstance(attribute, tuple):
-            new_attribute = list(attribute)
-            for j, item in enumerate(attribute):
-                if item == old:
-                    new_attribute[j] = new
-                    element[i] = new_attribute
+        if has_element_reference(attribute, old):
+            new_attribute = element.walk(lambda v: v == old, lambda v: new, attribute)
+            # TODO: make this unnecessary
+            if element.wrapped_data.file.transaction:
+                element.wrapped_data.file.transaction.store_edit(element, i, new_attribute)
+            element[i] = new_attribute
+
+
+def has_element_reference(value, element):
+    if isinstance(value, (tuple, list)):
+        for v in value:
+            return has_element_reference(v, element)
+    return value == element
 
 
 def remove_deep(ifc_file, element):