[IMP] - read may be harmful to performance

onchange_helper/__manifest__.py

@@ -4,7 +4,8 @@
 {
     'name': 'Onchange Helper',
     'version': '12.0.1.0.0',
-    'summary': 'Technical module that ease execution of onchange in Python code',
+    'summary': 'Technical module that ease execution'
+    ' of onchange in Python code',
     'author': 'Akretion,Camptocamp,Odoo Community Association (OCA)',
     'website': 'https://github.com/OCA/server-tools',
     'license': 'AGPL-3',

onchange_helper/models/base.py

@@ -31,7 +31,12 @@ class Base(models.AbstractModel):
         # If self is an empty record we will have an empty value
         if self:
             self.ensure_one()
-            record_values = self._convert_to_write(self.read()[0])
+            record_values = self._convert_to_write(
+                {
+                    field_name: self[field_name]
+                    for field_name, field in self._fields.items()
+                }
+            )
         else:
             record_values = {}
         for field in self._fields: