@@ -1134,6 +1136,121 @@ def test_edit_carddata_invalid_file_field(pub):
     assert carddata.data == {'0': 'new value', '4': None}
 
 
+def test_edit_carddata_partial_block_field(pub, admin_user):

@@ -1137,0 +1227,4 @@
+    assert carddata.data == {
+        '0': 'new value',
+        '1': {
+            'data': [{'123': 'new subfield value', '234': None}, {'123': 'new subfield value', '234': None}],

@@ -294,2 +294,4 @@
         elif value and not (isinstance(value, dict) and 'data' in value and 'schema' in value):
             raise SetValueError(_('invalid value for block (field id: %s)') % self.id)
+        elif value:
+            value = copy.deepcopy(value)

@@ -79,0 +78,4 @@
+        for field in formdef.get_widget_fields():
+            options.append((field.id, field.label, str(field.id)))
+            if field.key == 'block':
+                for subfield in field.block.get_widget_fields():

@@ -120,0 +128,4 @@
+        ranks = {}
+        i = 0
+        for field in self.to_formdef.get_widget_fields():
+            ranks[str(field.id)] = i

@@ -542,0 +557,4 @@
+            self.cached_field_labels = {}
+            for field in self.formdef.get_widget_fields():
+                if field.id in mapped_field_ids:
+                    self.cached_field_labels[field.id] = field.label

@@ -784,0 +808,4 @@
+        for field in self.formdef.get_widget_fields():
+            if field.key == 'block':
+                for subfield in field.block.get_widget_fields():
+                    to_id_fields[f'{field.id}${subfield.id}'] = subfield

@@ -834,0 +868,4 @@
+            if not formdata.data.get(parent_block_field.id):
+                formdata.data[parent_block_field.id] = BlockRowValue().make_value(
+                    block=parent_block_field.block, field=parent_block_field, data={}
+                )

@@ -834,0 +871,4 @@
+                )
+            for sub_data in formdata.data[parent_block_field.id]['data']:
+                field.set_value(sub_data, value)
+            formdata.data[f'{parent_block_field.id}_display'] = parent_block_field.store_display_value(