--- /dev/null
+<?php
+
+namespace Drupal\datetime\Plugin\views\argument;
+
+/**
+ * Argument handler for a day.
+ *
+ * @ViewsArgument("datetime_day")
+ */
+class DayDate extends Date {
+
+ /**
+ * {@inheritdoc}
+ */
+ protected $argFormat = 'd';
+
+}