From 6df24465f4b145080277fff3b7ca8c3d1b7db9d4 Mon Sep 17 00:00:00 2001
From: Boone Gorges <boonebgorges@git.wordpress.org>
Date: Tue, 28 Oct 2014 18:12:30 +0000
Subject: [PATCH] Introduce `orderby=include` support for `get_terms()`.

Props wpsmith.
Fixes #23261.

git-svn-id: https://develop.svn.wordpress.org/trunk@30052 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/taxonomy.php          |  3 +++
 tests/phpunit/tests/term/getTerms.php | 24 ++++++++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/src/wp-includes/taxonomy.php b/src/wp-includes/taxonomy.php
index fffc05f986..defc36cd8e 100644
--- a/src/wp-includes/taxonomy.php
+++ b/src/wp-includes/taxonomy.php
@@ -1712,6 +1712,9 @@ function get_terms( $taxonomies, $args = '' ) {
 		$orderby = 't.name';
 	} else if ( 'slug' == $_orderby ) {
 		$orderby = 't.slug';
+	} else if ( 'include' == $_orderby && ! empty( $args['include'] ) ) {
+		$include = implode( ',', array_map( 'absint', $args['include'] ) );
+		$orderby = "FIELD( t.term_id, $include )";
 	} else if ( 'term_group' == $_orderby ) {
 		$orderby = 't.term_group';
 	} else if ( 'none' == $_orderby ) {
diff --git a/tests/phpunit/tests/term/getTerms.php b/tests/phpunit/tests/term/getTerms.php
index 47780ebf2b..f386796dd0 100644
--- a/tests/phpunit/tests/term/getTerms.php
+++ b/tests/phpunit/tests/term/getTerms.php
@@ -796,6 +796,30 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 		$this->assertEqualSets( $expected, $found );
 	}
 
+	/**
+	 * @ticket 23261
+	 */
+	public function test_orderby_include() {
+		$tax = 'wptests_tax';
+		register_taxonomy( $tax, 'post' );
+
+		$t1 = $this->factory->term->create( array( 'taxonomy' => $tax ) );
+		$t2 = $this->factory->term->create( array( 'taxonomy' => $tax ) );
+		$t3 = $this->factory->term->create( array( 'taxonomy' => $tax ) );
+		$t4 = $this->factory->term->create( array( 'taxonomy' => $tax ) );
+
+		$found = get_terms( $tax, array(
+			'fields' => 'ids',
+			'include' => array( $t4, $t1, $t2 ),
+			'orderby' => 'include',
+			'hide_empty' => false,
+		) );
+
+		_unregister_taxonomy( 'wptests_tax' );
+
+		$this->assertEquals( array( $t4, $t1, $t2 ), $found );
+	}
+
 	protected function create_hierarchical_terms_and_posts() {
 
 		$terms = array();