From c2c8a6848d861118f1ba8c42c798fe37a9a95021 Mon Sep 17 00:00:00 2001
From: Boone Gorges <boonebgorges@git.wordpress.org>
Date: Mon, 26 Aug 2019 15:18:40 +0000
Subject: [PATCH] Taxonomy: Fix unique-slug check for terms with parents.

`wp_unique_term_slug()` appends numeric suffixes when the requested slug is
already in use by a sibling term. Changes introduced in [32837] inadvertently
caused this suffixing to be skipped in cases where the requested slug is
suffixed with the parent slug, so that it became possible to have two terms
`childslug-parentslug` underneath to the same `parentslug`. We fix this
regression by ensuring that the numeric-suffix routine runs in all cases.

Props yashar_hv, saskak, dlh.
Fixes #46431.

git-svn-id: https://develop.svn.wordpress.org/trunk@45893 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/taxonomy.php                  | 30 ++++++-------
 tests/phpunit/tests/term/wpUniqueTermSlug.php | 45 +++++++++++++++++++
 2 files changed, 60 insertions(+), 15 deletions(-)

diff --git a/src/wp-includes/taxonomy.php b/src/wp-includes/taxonomy.php
index 2db5038ef1..dcfafb2cde 100644
--- a/src/wp-includes/taxonomy.php
+++ b/src/wp-includes/taxonomy.php
@@ -2745,22 +2745,22 @@ function wp_unique_term_slug( $slug, $term ) {
 	if ( apply_filters( 'wp_unique_term_slug_is_bad_slug', $needs_suffix, $slug, $term ) ) {
 		if ( $parent_suffix ) {
 			$slug .= $parent_suffix;
-		} else {
-			if ( ! empty( $term->term_id ) ) {
-				$query = $wpdb->prepare( "SELECT slug FROM $wpdb->terms WHERE slug = %s AND term_id != %d", $slug, $term->term_id );
-			} else {
-				$query = $wpdb->prepare( "SELECT slug FROM $wpdb->terms WHERE slug = %s", $slug );
-			}
+		}
 
-			if ( $wpdb->get_var( $query ) ) {
-				$num = 2;
-				do {
-					$alt_slug = $slug . "-$num";
-					$num++;
-					$slug_check = $wpdb->get_var( $wpdb->prepare( "SELECT slug FROM $wpdb->terms WHERE slug = %s", $alt_slug ) );
-				} while ( $slug_check );
-				$slug = $alt_slug;
-			}
+		if ( ! empty( $term->term_id ) ) {
+			$query = $wpdb->prepare( "SELECT slug FROM $wpdb->terms WHERE slug = %s AND term_id != %d", $slug, $term->term_id );
+		} else {
+			$query = $wpdb->prepare( "SELECT slug FROM $wpdb->terms WHERE slug = %s", $slug );
+		}
+
+		if ( $wpdb->get_var( $query ) ) { // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
+			$num = 2;
+			do {
+				$alt_slug = $slug . "-$num";
+				$num++;
+				$slug_check = $wpdb->get_var( $wpdb->prepare( "SELECT slug FROM $wpdb->terms WHERE slug = %s", $alt_slug ) );
+			} while ( $slug_check );
+			$slug = $alt_slug;
 		}
 	}
 
diff --git a/tests/phpunit/tests/term/wpUniqueTermSlug.php b/tests/phpunit/tests/term/wpUniqueTermSlug.php
index b81dca5b40..75501edab6 100644
--- a/tests/phpunit/tests/term/wpUniqueTermSlug.php
+++ b/tests/phpunit/tests/term/wpUniqueTermSlug.php
@@ -127,4 +127,49 @@ class Tests_Term_WpUniqueTermSlug extends WP_UnitTestCase {
 		$actual = wp_unique_term_slug( 'bar', $term2_object );
 		$this->assertEquals( 'bar-2', $actual );
 	}
+
+	/**
+	 * @ticket 46431
+	 */
+	public function test_duplicate_parent_suffixed_slug_should_get_numeric_suffix() {
+		$t1 = self::factory()->term->create(
+			array(
+				'taxonomy' => 'wptests_tax2',
+				'name'     => 'Animal',
+				'slug'     => 'animal',
+			)
+		);
+
+		$t2 = self::factory()->term->create(
+			array(
+				'taxonomy' => 'wptests_tax2',
+				'name'     => 'Dog',
+				'slug'     => 'dog',
+			)
+		);
+
+		$t3 = self::factory()->term->create(
+			array(
+				'taxonomy' => 'wptests_tax2',
+				'name'     => 'Cat',
+				'slug'     => 'dog-animal',
+				'parent'   => $t1,
+			)
+		);
+
+		$t4 = self::factory()->term->create(
+			array(
+				'taxonomy' => 'wptests_tax2',
+				'name'     => 'Giraffe',
+				'slug'     => 'giraffe',
+				'parent'   => $t1,
+			)
+		);
+
+		$term = get_term( $t4 );
+
+		$slug = wp_unique_term_slug( 'dog', $term );
+
+		$this->assertSame( 'dog-animal-2', $slug );
+	}
 }