ext/date: Change return type to static

UPGRADING

@@ -602,6 +602,23 @@ PHP 8.6 UPGRADE NOTES
     directive when $details is true. It holds the built-in default value of the
     directive (or null if it has none), independent of values set in php.ini,
     on the command line, or at runtime.
+
+- Date:
+  . The following DateTime, DateTimeImmutable, DateTimeZone, DateInterval, and DatePeriod methods now have tentative static return types:
+    DateTime::createFromInterface()
+    DateTimeImmutable::__set_state()
+    DateTimeImmutable::modify()
+    DateTimeImmutable::add()
+    DateTimeImmutable::sub()
+    DateTimeImmutable::setTimezone()
+    DateTimeImmutable::setTime()
+    DateTimeImmutable::setDate()
+    DateTimeImmutable::setISODate()
+    DateTimeImmutable::setTimestamp()
+    DateTimeImmutable::createFromInterface()
+    DateTimeZone::__set_state()
+    DateInterval::__set_state()
+    DatePeriod::__set_state()
 
 ========================================
 6. New Functions

ext/date/php_date.stub.php

@@ -349,8 +349,8 @@ public static function __set_state(array $array): DateTime {}
     /** @tentative-return-type */
     public static function createFromImmutable(DateTimeImmutable $object): static {}
 
-    /** @return static */
-    public static function createFromInterface(DateTimeInterface $object): DateTime {} // TODO return type should be static
+    /** @tentative-return-type */
+    public static function createFromInterface(DateTimeInterface $object): static {}
 
     /**
      * @tentative-return-type
@@ -462,7 +462,7 @@ public function __unserialize(array $data): void {}
     public function __wakeup(): void {}
 
     /** @tentative-return-type */
-    public static function __set_state(array $array): DateTimeImmutable {}
+    public static function __set_state(array $array): static {}
 
     /**
      * @tentative-return-type
@@ -517,44 +517,44 @@ public function diff(DateTimeInterface $targetObject, bool $absolute = false): D
 
     /** @tentative-return-type */
     #[\NoDiscard(message: "as DateTimeImmutable::modify() does not modify the object itself")]
-    public function modify(string $modifier): DateTimeImmutable {}
+    public function modify(string $modifier): static {}
 
     /** @tentative-return-type */
     #[\NoDiscard(message: "as DateTimeImmutable::add() does not modify the object itself")]
-    public function add(DateInterval $interval): DateTimeImmutable {}
+    public function add(DateInterval $interval): static {}
 
     /** @tentative-return-type */
     #[\NoDiscard(message: "as DateTimeImmutable::sub() does not modify the object itself")]
-    public function sub(DateInterval $interval): DateTimeImmutable {}
+    public function sub(DateInterval $interval): static {}
 
     /** @tentative-return-type */
     #[\NoDiscard(message: "as DateTimeImmutable::setTimezone() does not modify the object itself")]
-    public function setTimezone(DateTimeZone $timezone): DateTimeImmutable {}
+    public function setTimezone(DateTimeZone $timezone): static {}
 
     /** @tentative-return-type */
     #[\NoDiscard(message: "as DateTimeImmutable::setTime() does not modify the object itself")]
-    public function setTime(int $hour, int $minute, int $second = 0, int $microsecond = 0): DateTimeImmutable {}
+    public function setTime(int $hour, int $minute, int $second = 0, int $microsecond = 0): static {}
 
     /** @tentative-return-type */
     #[\NoDiscard(message: "as DateTimeImmutable::setDate() does not modify the object itself")]
-    public function setDate(int $year, int $month, int $day): DateTimeImmutable {}
+    public function setDate(int $year, int $month, int $day): static {}
 
     /** @tentative-return-type */
     #[\NoDiscard(message: "as DateTimeImmutable::setISODate() does not modify the object itself")]
-    public function setISODate(int $year, int $week, int $dayOfWeek = 1): DateTimeImmutable {}
+    public function setISODate(int $year, int $week, int $dayOfWeek = 1): static {}
 
     /** @tentative-return-type */
     #[\NoDiscard(message: "as DateTimeImmutable::setTimestamp() does not modify the object itself")]
-    public function setTimestamp(int $timestamp): DateTimeImmutable {}
+    public function setTimestamp(int $timestamp): static {}
 
     #[\NoDiscard(message: "as DateTimeImmutable::setMicrosecond() does not modify the object itself")]
     public function setMicrosecond(int $microsecond): static {}
 
     /** @tentative-return-type */
     public static function createFromMutable(DateTime $object): static {}
 
-    /** @return static */
-    public static function createFromInterface(DateTimeInterface $object): DateTimeImmutable {} // TODO return type should be static
+    /** @tentative-return-type */
+    public static function createFromInterface(DateTimeInterface $object): static {}
 }
 
 class DateTimeZone
@@ -639,7 +639,7 @@ public function __unserialize(array $data): void {}
     public function __wakeup(): void {}
 
     /** @tentative-return-type */
-    public static function __set_state(array $array): DateTimeZone {}
+    public static function __set_state(array $array): static {}
 }
 
 class DateInterval
@@ -666,7 +666,7 @@ public function __unserialize(array $data): void;
     public function __wakeup(): void {}
 
     /** @tentative-return-type */
-    public static function __set_state(array $array): DateInterval {}
+    public static function __set_state(array $array): static {}
 }
 
 class DatePeriod implements IteratorAggregate
@@ -743,7 +743,7 @@ public function __unserialize(array $data): void;
     public function __wakeup(): void {}
 
     /** @tentative-return-type */
-    public static function __set_state(array $array): DatePeriod {}
+    public static function __set_state(array $array): static {}
 
     public function getIterator(): Iterator {}
 }