Enforce validation on save for FieldPanels corresponding to non-null, non-text-type model fields

wagtail/admin/panels/field_panel.py

@@ -67,7 +67,10 @@ class FieldPanel(Panel):
             except FieldDoesNotExist:
                 required_on_save = False
             else:
-                required_on_save = getattr(db_field, "required_on_save", False)
+                required_on_save = getattr(db_field, "required_on_save", False) or (
+                    db_field.null is False
+                    and db_field.get_internal_type() not in ("CharField", "TextField")
+                )
 
         if not required_on_save:
             opts["defer_required_on_fields"] = [self.field_name]

wagtail/admin/tests/pages/test_create_page.py

@@ -672,6 +672,37 @@ class TestPageCreation(WagtailTestUtils, TestCase):
             ).exists()
         )
 
+    def test_cannot_create_page_with_blank_required_date(self):
+        """
+        A non-nullable, non-text field cannot be saved with a blank value, so we should
+        enforce requiredness even when saving as draft
+        """
+        post_data = {
+            "title": "Page with missing date",
+            "deadline": "",
+            "slug": "missing-date",
+        }
+        response = self.client.post(
+            reverse(
+                "wagtailadmin_pages:add",
+                args=("tests", "requireddatepage", self.root_page.id),
+            ),
+            post_data,
+        )
+        self.assertEqual(response.status_code, 200)
+
+        # Check that a form error was raised
+        self.assertFormError(
+            response.context["form"], "deadline", "This field is required."
+        )
+
+        # Page should not have been created
+        self.assertFalse(
+            Page.objects.filter(
+                path__startswith=self.root_page.path, slug="missing-date"
+            ).exists()
+        )
+
     def test_create_simplepage_scheduled(self):
         go_live_at = timezone.now() + datetime.timedelta(days=1)
         expire_at = timezone.now() + datetime.timedelta(days=2)

wagtail/test/testapp/migrations/0048_requireddatepage.py

@@ -0,0 +1,36 @@
+# Generated by Django 5.1.5 on 2025-02-28 00:28
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("tests", "0047_advertwithcustomuuidprimarykey_page"),
+        ("wagtailcore", "0094_alter_page_locale"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="RequiredDatePage",
+            fields=[
+                (
+                    "page_ptr",
+                    models.OneToOneField(
+                        auto_created=True,
+                        on_delete=django.db.models.deletion.CASCADE,
+                        parent_link=True,
+                        primary_key=True,
+                        serialize=False,
+                        to="wagtailcore.page",
+                    ),
+                ),
+                ("deadline", models.DateField()),
+            ],
+            options={
+                "abstract": False,
+            },
+            bases=("wagtailcore.page",),
+        ),
+    ]

wagtail/test/testapp/models.py

@@ -2487,3 +2487,12 @@ class CustomPermissionModel(models.Model):
 
 
 register_snippet(CustomPermissionModel)
+
+
+class RequiredDatePage(Page):
+    deadline = models.DateField()
+
+    content_panels = [
+        TitleFieldPanel("title", classname="title"),
+        FieldPanel("deadline"),
+    ]