From 50f01f47e3ce17eba49a1ead86be8865635e908f Mon Sep 17 00:00:00 2001
From: Sergey Biryukov <sergeybiryukov@git.wordpress.org>
Date: Mon, 9 Dec 2019 18:48:50 +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.
Fixes #48606.

git-svn-id: https://develop.svn.wordpress.org/trunk@46862 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/functions.php                 | 21 ++++++++++++-------
 .../tests/functions/maybeDeclineDate.php      | 20 ++++++++++++++++++
 2 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/src/wp-includes/functions.php b/src/wp-includes/functions.php
index 0709a41d12..500aa35a0e 100644
--- a/src/wp-includes/functions.php
+++ b/src/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/tests/phpunit/tests/functions/maybeDeclineDate.php b/tests/phpunit/tests/functions/maybeDeclineDate.php
index d888a2d53c..04b5612223 100644
--- a/tests/phpunit/tests/functions/maybeDeclineDate.php
+++ b/tests/phpunit/tests/functions/maybeDeclineDate.php
@@ -37,6 +37,8 @@ class Tests_Functions_MaybeDeclineDate extends WP_UnitTestCase {
 
 	/**
 	 * @ticket 36790
+	 * @ticket 37411
+	 * @ticket 48606
 	 * @dataProvider data_wp_maybe_decline_date
 	 */
 	public function test_wp_maybe_decline_date( $test_locale, $input, $output ) {
@@ -71,11 +73,15 @@ class Tests_Functions_MaybeDeclineDate extends WP_UnitTestCase {
 			array( 'ru_RU', '1 Январь 2016', '1 января 2016' ),
 			array( 'ru_RU', 'Январь 1st 2016', '1 января 2016' ),
 			array( 'ru_RU', 'Январь 1 2016', '1 января 2016' ),
+			array( 'ru_RU', 'Январь 1 16', '1 января 16' ),
+			array( 'ru_RU', 'Суббота, 19 Январь 2019 10:50', 'Суббота, 19 января 2019 10:50' ),
 			array( 'pl_PL', '1 Styczeń', '1 stycznia' ),
 			array( 'hr', '1. Siječanj', '1. siječnja' ),
 			array( 'ca', '1 de abril', "1 d'abril" ),
 			array( 'cs_CZ', '1. Červen', '1. června' ),
 			array( 'cs_CZ', '1. Červenec', '1. července' ),
+			array( 'it_IT', 'Lundeì 11 Novembre 2019', 'Lundeì 11 Novembre 2019' ),
+			array( 'el', 'Σάββατο, 19 Ιανουάριος 2019 10:50', 'Σάββατο, 19 Ιανουαρίου 2019 10:50' ),
 		);
 	}
 
@@ -116,6 +122,20 @@ class Tests_Functions_MaybeDeclineDate extends WP_UnitTestCase {
 				);
 				break;
 
+			case 'it_IT':
+				$months = array(
+					'month'          => array( 'Gennaio', 'Febbraio', 'Marzo', 'Aprile', 'Maggio', 'Giugno', 'Luglio', 'Agosto', 'Settembre', 'Ottobre', 'Novembre', 'Dicembre' ),
+					'month_genitive' => array( 'Gennaio', 'Febbraio', 'Marzo', 'Aprile', 'Maggio', 'Giugno', 'Luglio', 'Agosto', 'Settembre', 'Ottobre', 'Novembre', 'Dicembre' ),
+				);
+				break;
+
+			case 'el':
+				$months = array(
+					'month'          => array( 'Ιανουάριος', 'Φεβρουάριος', 'Μάρτιος', 'Απρίλιος', 'Μάιος', 'Ιούνιος', 'Ιούλιος', 'Αύγουστος', 'Σεπτέμβριος', 'Οκτώβριος', 'Νοέμβριος', 'Δεκέμβριος' ),
+					'month_genitive' => array( 'Ιανουαρίου', 'Φεβρουαρίου', 'Μαρτίου', 'Απριλίου', 'Μαΐου', 'Ιουνίου', 'Ιουλίου', 'Αυγούστου', 'Σεπτεμβρίου', 'Οκτωβρίου', 'Νοεμβρίου', 'Δεκεμβρίου' ),
+				);
+				break;
+
 			default:
 				$months = array(
 					'month'          => array( 'January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December' ),