From b91ac6c7f08465b36e9d1b38ebc9b223dc17dd4a Mon Sep 17 00:00:00 2001
From: Gary Jones <gary@gamajo.com>
Date: Thu, 20 Jun 2019 13:16:27 +0200
Subject: [PATCH 1/2] Docs: Add TimezoneChange XML doc

See #1722.
---
 WordPress/Docs/WP/TimezoneChangeStandard.xml | 22 ++++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 WordPress/Docs/WP/TimezoneChangeStandard.xml

diff --git a/WordPress/Docs/WP/TimezoneChangeStandard.xml b/WordPress/Docs/WP/TimezoneChangeStandard.xml
new file mode 100644
index 0000000000..08ed87f6b6
--- /dev/null
+++ b/WordPress/Docs/WP/TimezoneChangeStandard.xml
@@ -0,0 +1,22 @@
+<documentation title="Disallow the changing of timezone.">
+    <standard>
+    <![CDATA[
+      Using date_default_timezone_set() and similar isn't allowed, instead use WP internal timezone support.
+    ]]>
+    </standard>
+    <code_comparison>
+        <code title="Valid: Using WP internal timezone support.">
+        <![CDATA[
+$date = new DateTime();
+$date->setTimezone(
+    new DateTimeZone( 'America/Toronto' )
+);
+        ]]>
+        </code>
+        <code title="Invalid: date_default_timezone_set() is used.">
+        <![CDATA[
+date_default_timezone_set( 'Foo/Bar' );
+        ]]>
+        </code>
+    </code_comparison>
+</documentation>

From c6e560b272f442d74418b6f7ae5ac1e5bd81b47b Mon Sep 17 00:00:00 2001
From: Gary Jones <gary.jones@automattic.com>
Date: Mon, 28 Mar 2022 16:50:20 +0100
Subject: [PATCH 2/2] Docs: Refresh restricted datetime functions docs

Kept the descriptions for individual code comparisons simpler, and populated the <standard> element with more description instead.
---
 .../DateTime/RestrictedFunctionsStandard.xml  | 50 +++++++++++++++++++
 WordPress/Docs/WP/TimezoneChangeStandard.xml  | 22 --------
 2 files changed, 50 insertions(+), 22 deletions(-)
 create mode 100644 WordPress/Docs/DateTime/RestrictedFunctionsStandard.xml
 delete mode 100644 WordPress/Docs/WP/TimezoneChangeStandard.xml

diff --git a/WordPress/Docs/DateTime/RestrictedFunctionsStandard.xml b/WordPress/Docs/DateTime/RestrictedFunctionsStandard.xml
new file mode 100644
index 0000000000..c8cc932cc9
--- /dev/null
+++ b/WordPress/Docs/DateTime/RestrictedFunctionsStandard.xml
@@ -0,0 +1,50 @@
+<documentation title="Restricted Date and Time Functions">
+    <standard>
+    <![CDATA[
+    The restricted functions date_default_timezone_set() and date() should not be used.
+    ]]>
+    </standard>
+    <standard>
+    <![CDATA[
+    Using the PHP native date_default_timezone_set() function isn't allowed, because WordPress Core needs the default time zone to be set to UTC for timezone calculations using the WP Core API to work correctly.
+    ]]>
+    </standard>
+    <code_comparison>
+        <code title="Valid: Using DateTime object.">
+        <![CDATA[
+$date = new <em>DateTime()</em>;
+$date->setTimezone(
+    new DateTimeZone( 'Europe/Amsterdam' )
+);
+        ]]>
+        </code>
+        <code title="Invalid: Using date_default_timezone_set().">
+        <![CDATA[
+<em>date_default_timezone_set</em>( 'Europe/Amsterdam' );
+        ]]>
+        </code>
+    </code_comparison>
+    <standard>
+    <![CDATA[
+    Using the PHP native date() function isn't allowed, as it is affected by runtime timezone changes which can cause the date/time to be incorrectly displayed. Use gmdate() instead.
+    ]]>
+    </standard>
+    <code_comparison>
+        <code title="Valid: Using gmdate().">
+        <![CDATA[
+$last_updated = <em>gmdate</em>(
+    'Y-m-d\TH:i:s',
+    strtotime( $plugin['last_updated'] )
+);
+        ]]>
+        </code>
+        <code title="Invalid: Using date().">
+        <![CDATA[
+$last_updated = <em>date</em>(
+    'Y-m-d\TH:i:s',
+    strtotime( $plugin['last_updated'] )
+);
+        ]]>
+        </code>
+    </code_comparison>
+</documentation>
diff --git a/WordPress/Docs/WP/TimezoneChangeStandard.xml b/WordPress/Docs/WP/TimezoneChangeStandard.xml
deleted file mode 100644
index 08ed87f6b6..0000000000
--- a/WordPress/Docs/WP/TimezoneChangeStandard.xml
+++ /dev/null
@@ -1,22 +0,0 @@
-<documentation title="Disallow the changing of timezone.">
-    <standard>
-    <![CDATA[
-      Using date_default_timezone_set() and similar isn't allowed, instead use WP internal timezone support.
-    ]]>
-    </standard>
-    <code_comparison>
-        <code title="Valid: Using WP internal timezone support.">
-        <![CDATA[
-$date = new DateTime();
-$date->setTimezone(
-    new DateTimeZone( 'America/Toronto' )
-);
-        ]]>
-        </code>
-        <code title="Invalid: date_default_timezone_set() is used.">
-        <![CDATA[
-date_default_timezone_set( 'Foo/Bar' );
-        ]]>
-        </code>
-    </code_comparison>
-</documentation>