Fixed #31640 -- Made Trunc() truncate datetimes to Date/TimeField in a specific timezone.

1 files changed, 5 insertions, 3 deletions

diff --git a/django/db/backends/postgresql/operations.py b/django/db/backends/postgresql/operations.py
index 1ce5755bf5..8d19872bea 100644
--- a/django/db/backends/postgresql/operations.py
+++ b/django/db/backends/postgresql/operations.py
@@ -38,7 +38,8 @@ class DatabaseOperations(BaseDatabaseOperations):
         else:
             return "EXTRACT('%s' FROM %s)" % (lookup_type, field_name)
 
-    def date_trunc_sql(self, lookup_type, field_name):
+    def date_trunc_sql(self, lookup_type, field_name, tzname=None):
+        field_name = self._convert_field_to_tz(field_name, tzname)
         # https://www.postgresql.org/docs/current/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
         return "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
 
@@ -50,7 +51,7 @@ class DatabaseOperations(BaseDatabaseOperations):
         return tzname
 
     def _convert_field_to_tz(self, field_name, tzname):
-        if settings.USE_TZ:
+        if tzname and settings.USE_TZ:
             field_name = "%s AT TIME ZONE '%s'" % (field_name, self._prepare_tzname_delta(tzname))
         return field_name
 
@@ -71,7 +72,8 @@ class DatabaseOperations(BaseDatabaseOperations):
         # https://www.postgresql.org/docs/current/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
         return "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
 
-    def time_trunc_sql(self, lookup_type, field_name):
+    def time_trunc_sql(self, lookup_type, field_name, tzname=None):
+        field_name = self._convert_field_to_tz(field_name, tzname)
         return "DATE_TRUNC('%s', %s)::time" % (lookup_type, field_name)
 
     def deferrable_sql(self):