From 6f5e07a84d65496abcdb876170c513c4a3840760 Mon Sep 17 00:00:00 2001
From: Chris Jerdonek <chris.jerdonek@gmail.com>
Date: Thu, 29 Jul 2021 01:47:24 -0400
Subject: [PATCH] Refs #32966 -- Refactored out
 DateTimeCheckMixin._check_if_value_fixed().

---
 django/db/models/fields/__init__.py | 109 +++++++++++-----------------
 1 file changed, 42 insertions(+), 67 deletions(-)

diff --git a/django/db/models/fields/__init__.py b/django/db/models/fields/__init__.py
index 676a00acfd..1e8637d2f7 100644
--- a/django/db/models/fields/__init__.py
+++ b/django/db/models/fields/__init__.py
@@ -1144,6 +1144,42 @@ class DateTimeCheckMixin:
     def _check_fix_default_value(self):
         return []
 
+    # Concrete subclasses use this in their implementations of
+    # _check_fix_default_value().
+    def _check_if_value_fixed(self, value, now=None):
+        """
+        Check if the given value appears to have been provided as a "fixed"
+        time value, and include a warning in the returned list if it does. The
+        value argument must be a date object or aware/naive datetime object. If
+        now is provided, it must be a naive datetime object.
+        """
+        if now is None:
+            now = _get_naive_now()
+        offset = datetime.timedelta(seconds=10)
+        lower = now - offset
+        upper = now + offset
+        if isinstance(value, datetime.datetime):
+            value = _to_naive(value)
+        else:
+            assert isinstance(value, datetime.date)
+            lower = lower.date()
+            upper = upper.date()
+        if lower <= value <= upper:
+            return [
+                checks.Warning(
+                    'Fixed default value provided.',
+                    hint=(
+                        'It seems you set a fixed date / time / datetime '
+                        'value as default for this field. This may not be '
+                        'what you want. If you want to have the current date '
+                        'as default, use `django.utils.timezone.now`'
+                    ),
+                    obj=self,
+                    id='fields.W161',
+                )
+            ]
+        return []
+
 
 class DateField(DateTimeCheckMixin, Field):
     empty_strings_allowed = False
@@ -1175,30 +1211,12 @@ class DateField(DateTimeCheckMixin, Field):
         if isinstance(value, datetime.datetime):
             value = _to_naive(value).date()
         elif isinstance(value, datetime.date):
-            # Nothing to do, as dates don't have tz information
             pass
         else:
             # No explicit date / datetime value -- no checks necessary
             return []
         # At this point, value is a date object.
-        today = _get_naive_now().date()
-        offset = datetime.timedelta(days=1)
-        lower = today - offset
-        upper = today + offset
-        if lower <= value <= upper:
-            return [
-                checks.Warning(
-                    'Fixed default value provided.',
-                    hint='It seems you set a fixed date / time / datetime '
-                         'value as default for this field. This may not be '
-                         'what you want. If you want to have the current date '
-                         'as default, use `django.utils.timezone.now`',
-                    obj=self,
-                    id='fields.W161',
-                )
-            ]
-
-        return []
+        return self._check_if_value_fixed(value)
 
     def deconstruct(self):
         name, path, args, kwargs = super().deconstruct()
@@ -1309,35 +1327,9 @@ class DateTimeField(DateField):
             return []
 
         value = self.default
-        if isinstance(value, datetime.datetime):
-            value = _to_naive(value)
-            now = _get_naive_now()
-            offset = datetime.timedelta(seconds=10)
-            lower = now - offset
-            upper = now + offset
-        elif isinstance(value, datetime.date):
-            now = _get_naive_now()
-            offset = datetime.timedelta(seconds=10)
-            lower = now - offset
-            upper = now + offset
-            lower = lower.date()
-            upper = upper.date()
-        else:
-            # No explicit date / datetime value -- no checks necessary
-            return []
-        if lower <= value <= upper:
-            return [
-                checks.Warning(
-                    'Fixed default value provided.',
-                    hint='It seems you set a fixed date / time / datetime '
-                         'value as default for this field. This may not be '
-                         'what you want. If you want to have the current date '
-                         'as default, use `django.utils.timezone.now`',
-                    obj=self,
-                    id='fields.W161',
-                )
-            ]
-
+        if isinstance(value, (datetime.datetime, datetime.date)):
+            return self._check_if_value_fixed(value)
+        # No explicit date / datetime value -- no checks necessary.
         return []
 
     def get_internal_type(self):
@@ -2203,7 +2195,7 @@ class TimeField(DateTimeCheckMixin, Field):
 
         value = self.default
         if isinstance(value, datetime.datetime):
-            now = _get_naive_now()
+            now = None
         elif isinstance(value, datetime.time):
             now = _get_naive_now()
             # This will not use the right date in the race condition where now
@@ -2213,24 +2205,7 @@ class TimeField(DateTimeCheckMixin, Field):
             # No explicit time / datetime value -- no checks necessary
             return []
         # At this point, value is a datetime object.
-        offset = datetime.timedelta(seconds=10)
-        lower = now - offset
-        upper = now + offset
-        value = _to_naive(value)
-        if lower <= value <= upper:
-            return [
-                checks.Warning(
-                    'Fixed default value provided.',
-                    hint='It seems you set a fixed date / time / datetime '
-                         'value as default for this field. This may not be '
-                         'what you want. If you want to have the current date '
-                         'as default, use `django.utils.timezone.now`',
-                    obj=self,
-                    id='fields.W161',
-                )
-            ]
-
-        return []
+        return self._check_if_value_fixed(value, now=now)
 
     def deconstruct(self):
         name, path, args, kwargs = super().deconstruct()