docs: add docs

Author: kenjis

user_guide_src/source/changelogs/v4.6.0.rst

@@ -57,14 +57,22 @@ Added check to prevent Auto-Discovery of Registrars from running twice. If it is
 executed twice, an exception will be thrown. See
 :ref:`upgrade-460-registrars-with-dirty-hack`.
 
-.. _v460-interface-changes:
+Time::createFromTimestamp()
+---------------------------
+
+``Time::createFromTimestamp()`` handles timezones differently. If ``$timezone``
+is not explicitly passed then the instance has timezone set to UTC unlike earlier
+where the currently set default timezone was used.
+See :ref:`Upgrading Guide <upgrade-460-time-create-from-timestamp>` for details.
 
 Time with Microseconds
 ----------------------
 
 Fixed bugs that some methods in ``Time`` to lose microseconds have been fixed.
 See :ref:`Upgrading Guide <upgrade-460-time-keeps-microseconds>` for details.
 
+.. _v460-interface-changes:
+
 Interface Changes
 =================
 

user_guide_src/source/installation/upgrade_460.rst

@@ -29,6 +29,26 @@ See :ref:`ChangeLog <v460-behavior-changes-exceptions>` for details.
 
 If you have code that catches these exceptions, change the exception classes.
 
+.. _upgrade-460-time-create-from-timestamp:
+
+Time::createFromTimestamp() Timezone Change
+===========================================
+
+When you do not explicitly pass a timezone, now
+:ref:`Time::createFromTimestamp() <time-createfromtimestamp>` returns a Time
+instance with **UTC**. In v4.4.6 to prior to v4.6.0, a Time instance with the
+currently set default timezone was returned.
+
+This behavior change normalizes behavior with changes in PHP 8.4 which adds a
+new ``DateTimeInterface::createFromTimestamp()`` method.
+
+If you want to keep the default timezone, you need to pass the timezone as the
+second parameter::
+
+    use CodeIgniter\I18n\Time;
+
+    $time = Time::createFromTimestamp(1501821586, date_default_timezone_get());
+
 .. _upgrade-460-time-keeps-microseconds:
 
 Time keeps Microseconds

user_guide_src/source/libraries/time.rst

@@ -126,8 +126,10 @@ This method takes a UNIX timestamp and, optionally, the timezone and locale, to
 
 .. literalinclude:: time/012.php
 
-.. note:: Due to a bug, prior to v4.4.6, this method returned a Time instance
-    in timezone UTC when you do not specify a timezone.
+If you do not explicitly pass a timezone, it returns a Time instance with **UTC**.
+
+.. note:: In v4.4.6 to prior to v4.6.0, this method returned a Time instance
+    with the default timezone when you do not specify a timezone.
 
 createFromInstance()
 ====================