From e5f1a70a8783183e8997be4d35f677fae7ed2d4c Mon Sep 17 00:00:00 2001
From: Sergey Biryukov <sergeybiryukov.ru@gmail.com>
Date: Mon, 9 Dec 2019 19:02:04 +0000
Subject: [PATCH] Date/Time: When determining whether to decline the month name
 in `wp_maybe_decline_date()`, take word boundaries into account.

Add more unit tests.

Props Rarst, Clorith, timon33, Xendo, SergeyBiryukov.
Merges [46862] to the 5.3 branch.
Fixes #48606.
Built from https://develop.svn.wordpress.org/branches/5.3@46863


git-svn-id: http://core.svn.wordpress.org/branches/5.3@46663 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/functions.php | 21 +++++++++++++--------
 wp-includes/version.php   |  2 +-
 2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/wp-includes/functions.php b/wp-includes/functions.php
index 5fea050bdc..b80e85fe1f 100644
--- a/wp-includes/functions.php
+++ b/wp-includes/functions.php
@@ -335,24 +335,29 @@ function wp_maybe_decline_date( $date ) {
 		$months          = $wp_locale->month;
 		$months_genitive = $wp_locale->month_genitive;
 
-		// Match a format like 'j F Y' or 'j. F'
-		if ( preg_match( '#^\d{1,2}\.? [^\d ]+#u', $date ) ) {
-
+		/*
+		 * Match a format like 'j F Y' or 'j. F' (day of the month, followed by month name)
+		 * and decline the month.
+		 */
+		if ( preg_match( '#\b\d{1,2}\.? [^\d ]+\b#u', $date ) ) {
 			foreach ( $months as $key => $month ) {
-				$months[ $key ] = '# ' . $month . '( |$)#u';
+				$months[ $key ] = '# ' . preg_quote( $month, '#' ) . '\b#u';
 			}
 
 			foreach ( $months_genitive as $key => $month ) {
-				$months_genitive[ $key ] = ' ' . $month . '$1';
+				$months_genitive[ $key ] = ' ' . $month;
 			}
 
 			$date = preg_replace( $months, $months_genitive, $date );
 		}
 
-		// Match a format like 'F jS' or 'F j' and change it to 'j F'
-		if ( preg_match( '#^[^\d ]+ \d{1,2}(st|nd|rd|th)? #u', trim( $date ) ) ) {
+		/*
+		 * Match a format like 'F jS' or 'F j' (month name, followed by day with an optional ordinal suffix)
+		 * and change it to declined 'j F'.
+		 */
+		if ( preg_match( '#\b[^\d ]+ \d{1,2}(st|nd|rd|th)?\b#u', trim( $date ) ) ) {
 			foreach ( $months as $key => $month ) {
-				$months[ $key ] = '#' . $month . ' (\d{1,2})(st|nd|rd|th)?#u';
+				$months[ $key ] = '#\b' . preg_quote( $month, '#' ) . ' (\d{1,2})(st|nd|rd|th)?\b#u';
 			}
 
 			foreach ( $months_genitive as $key => $month ) {
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 12821ac9fd..5b853b154f 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.3.1-alpha-46861';
+$wp_version = '5.3.1-alpha-46863';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.