Prevent catalog/invoice cost edits if receiving batch is complete

tailbone/views/purchasing/receiving.py

@@ -737,14 +737,36 @@ class ReceivingBatchView(PurchasingBatchView):
         return breakdown
 
     def allow_edit_catalog_unit_cost(self, batch):
-        return (not batch.executed
-                and self.has_perm('edit_row')
-                and self.batch_handler.allow_receiving_edit_catalog_unit_cost())
+
+        # batch must not yet be frozen
+        if batch.executed or batch.complete:
+            return False
+
+        # user must have edit_row perm
+        if not self.has_perm('edit_row'):
+            return False
+
+        # config must allow this generally
+        if not self.batch_handler.allow_receiving_edit_catalog_unit_cost():
+            return False
+
+        return True
 
     def allow_edit_invoice_unit_cost(self, batch):
-        return (not batch.executed
-                and self.has_perm('edit_row')
-                and self.batch_handler.allow_receiving_edit_invoice_unit_cost())
+
+        # batch must not yet be frozen
+        if batch.executed or batch.complete:
+            return False
+
+        # user must have edit_row perm
+        if not self.has_perm('edit_row'):
+            return False
+
+        # config must allow this generally
+        if not self.batch_handler.allow_receiving_edit_invoice_unit_cost():
+            return False
+
+        return True
 
     def template_kwargs_view(self, **kwargs):
         kwargs = super(ReceivingBatchView, self).template_kwargs_view(**kwargs)