docs: add user guide

Author: kenjis

user_guide_src/source/changelogs/v4.4.6.rst

@@ -14,6 +14,15 @@ Release Date: Unreleased
 BREAKING
 ********
 
+Time::createFromTimestamp()
+===========================
+
+A bug that caused :ref:`Time::createFromTimestamp() <time-createfromtimestamp>`
+to return a Time instance with a timezone of UTC has been fixed.
+
+Starting with this version, when you do not specify a timezone, a Time instance
+with the app's timezone is returned by default.
+
 ***************
 Message Changes
 ***************

user_guide_src/source/installation/upgrade_446.rst

@@ -20,6 +20,20 @@ Mandatory File Changes
 Breaking Changes
 ****************
 
+Time::createFromTimestamp() Timezone Change
+===========================================
+
+When you do not specify a timezone, now
+:ref:`Time::createFromTimestamp() <time-createfromtimestamp>` returns a Time
+instance with the app's timezone is returned.
+
+If you want to keep the timezone UTC, you need to call ``setTimezone('UTC')``::
+
+    use CodeIgniter\I18n\Time;
+
+    $time = Time::createFromTimestamp(1501821586)->setTimezone('UTC');
+
+
 *********************
 Breaking Enhancements
 *********************

user_guide_src/source/libraries/time.rst

@@ -114,13 +114,18 @@ and returns a ``Time`` instance, instead of DateTimeImmutable:
 
 .. literalinclude:: time/011.php
 
+.. _time-createfromtimestamp:
+
 createFromTimestamp()
 =====================
 
 This method takes a UNIX timestamp and, optionally, the timezone and locale, to create a new Time instance:
 
 .. 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.
+
 createFromInstance()
 ====================