From 39a9f8671e71b8198b676edd60d0eb6aae91a197 Mon Sep 17 00:00:00 2001
From: Swen Kooij <swen@sectorlabs.ro>
Date: Wed, 24 Feb 2021 09:51:54 +0200
Subject: [PATCH] Apply converters to results return in upsert_and_get

---
 psqlextra/query.py   | 32 ++++++++++++++++++++++++++++----
 tests/test_upsert.py | 16 ++++++++++++++++
 2 files changed, 44 insertions(+), 4 deletions(-)

diff --git a/psqlextra/query.py b/psqlextra/query.py
index 02eaadf5..7369a0cc 100644
--- a/psqlextra/query.py
+++ b/psqlextra/query.py
@@ -3,7 +3,7 @@
 from typing import Dict, Iterable, List, Optional, Tuple, Union
 
 from django.core.exceptions import SuspiciousOperation
-from django.db import models, router
+from django.db import connections, models, router
 from django.db.models import Expression
 from django.db.models.fields import NOT_PROVIDED
 
@@ -389,14 +389,36 @@ def is_empty(r):
         )
         return self.bulk_insert(rows, return_model, using=using)
 
-    def _create_model_instance(self, field_values, using: Optional[str] = None):
+    def _create_model_instance(
+        self, field_values: dict, using: str, apply_converters: bool = True
+    ):
         """Creates a new instance of the model with the specified field.
 
         Use this after the row was inserted into the database. The new
         instance will marked as "saved".
         """
 
-        instance = self.model(**field_values)
+        converted_field_values = field_values.copy()
+
+        if apply_converters:
+            connection = connections[using]
+
+            for field in self.model._meta.local_concrete_fields:
+                if field.attname not in converted_field_values:
+                    continue
+
+                # converters can be defined on the field, or by
+                # the database back-end we're using
+                converters = field.get_db_converters(
+                    connection
+                ) + connection.ops.get_db_converters(field)
+
+                for converter in converters:
+                    converted_field_values[field.attname] = converter(
+                        converted_field_values[field.attname], field, connection
+                    )
+
+        instance = self.model(**converted_field_values)
         instance._state.db = using
         instance._state.adding = False
 
@@ -444,7 +466,9 @@ def _build_insert_compiler(
                     ).format(index)
                 )
 
-            objs.append(self._create_model_instance(row, using))
+            objs.append(
+                self._create_model_instance(row, using, apply_converters=False)
+            )
 
         # get the fields to be used during update/insert
         insert_fields, update_fields = self._get_upsert_fields(first_row)
diff --git a/tests/test_upsert.py b/tests/test_upsert.py
index 8cf94eb1..b04e09ea 100644
--- a/tests/test_upsert.py
+++ b/tests/test_upsert.py
@@ -106,6 +106,22 @@ def test_upsert_with_update_condition():
     assert not obj1.active
 
 
+def test_upsert_and_get_applies_converters():
+    """Tests that converters are properly applied when using upsert_and_get."""
+
+    class MyCustomField(models.TextField):
+        def from_db_value(self, value, expression, connection):
+            return value.replace("hello", "bye")
+
+    model = get_fake_model({"title": MyCustomField(unique=True)})
+
+    obj = model.objects.upsert_and_get(
+        conflict_target=["title"], fields=dict(title="hello")
+    )
+
+    assert obj.title == "bye"
+
+
 def test_upsert_bulk():
     """Tests whether bulk_upsert works properly."""