From 9d3a6394fb35d062497844a42548538155d3d2e1 Mon Sep 17 00:00:00 2001
From: Boone Gorges <boonebgorges@git.wordpress.org>
Date: Mon, 26 Jan 2015 19:03:09 +0000
Subject: [PATCH] Ensure that 'hierarchical' is respected in `get_terms()` when
 multiple taxonomies are passed.

Previously, attempts to descend the family tree of each term were done using
the first taxonomy in the `$taxonomies` array, with the result that terms not
belonging to that taxonomy were not found and their children not properly
parsed. We fix this bug by fetching each term's taxonomy with the SQL query,
and then using that taxonomy to get the correct children for each term.

Fixes #31118.

git-svn-id: https://develop.svn.wordpress.org/trunk@31285 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/taxonomy.php          | 13 +++++----
 tests/phpunit/tests/term/getTerms.php | 42 +++++++++++++++++++++++++++
 2 files changed, 49 insertions(+), 6 deletions(-)

diff --git a/src/wp-includes/taxonomy.php b/src/wp-includes/taxonomy.php
index 0419e97424..16bdf26ae8 100644
--- a/src/wp-includes/taxonomy.php
+++ b/src/wp-includes/taxonomy.php
@@ -1887,10 +1887,10 @@ function get_terms( $taxonomies, $args = '' ) {
 			break;
 		case 'ids':
 		case 'id=>parent':
-			$selects = array( 't.term_id', 'tt.parent', 'tt.count' );
+			$selects = array( 't.term_id', 'tt.parent', 'tt.count', 'tt.taxonomy' );
 			break;
 		case 'names':
-			$selects = array( 't.term_id', 'tt.parent', 'tt.count', 't.name' );
+			$selects = array( 't.term_id', 'tt.parent', 'tt.count', 't.name', 'tt.taxonomy' );
 			break;
 		case 'count':
 			$orderby = '';
@@ -1898,10 +1898,10 @@ function get_terms( $taxonomies, $args = '' ) {
 			$selects = array( 'COUNT(*)' );
 			break;
 		case 'id=>name':
-			$selects = array( 't.term_id', 't.name', 'tt.count' );
+			$selects = array( 't.term_id', 't.name', 'tt.count', 'tt.taxonomy' );
 			break;
 		case 'id=>slug':
-			$selects = array( 't.term_id', 't.slug', 'tt.count' );
+			$selects = array( 't.term_id', 't.slug', 'tt.count', 'tt.taxonomy' );
 			break;
 	}
 
@@ -1974,14 +1974,15 @@ function get_terms( $taxonomies, $args = '' ) {
 			_pad_term_counts( $terms, $_tax );
 		}
 	}
+
 	// Make sure we show empty categories that have children.
 	if ( $hierarchical && $args['hide_empty'] && is_array( $terms ) ) {
 		foreach ( $terms as $k => $term ) {
 			if ( ! $term->count ) {
-				$children = get_term_children( $term->term_id, reset( $taxonomies ) );
+				$children = get_term_children( $term->term_id, $term->taxonomy );
 				if ( is_array( $children ) ) {
 					foreach ( $children as $child_id ) {
-						$child = get_term( $child_id, reset( $taxonomies ) );
+						$child = get_term( $child_id, $term->taxonomy );
 						if ( $child->count ) {
 							continue 2;
 						}
diff --git a/tests/phpunit/tests/term/getTerms.php b/tests/phpunit/tests/term/getTerms.php
index 7abc13d622..ae8e71d4b4 100644
--- a/tests/phpunit/tests/term/getTerms.php
+++ b/tests/phpunit/tests/term/getTerms.php
@@ -1069,6 +1069,48 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 		$this->assertEqualSetsWithIndex( $expected, $found );
 	}
 
+	/**
+	 * @ticket 31118
+	 */
+	public function test_hierarchical_should_recurse_properly_for_all_taxonomies() {
+		register_taxonomy( 'wptests_tax1', 'post', array( 'hierarchical' => true ) );
+		register_taxonomy( 'wptests_tax2', 'post', array( 'hierarchical' => true ) );
+
+		$t1 = $this->factory->term->create( array( 'taxonomy' => 'wptests_tax1' ) );
+		$t2 = $this->factory->term->create( array( 'taxonomy' => 'wptests_tax1', 'parent' => $t1 ) );
+		$t3 = $this->factory->term->create( array( 'taxonomy' => 'wptests_tax1', 'parent' => $t2 ) );
+
+		$t4 = $this->factory->term->create( array( 'taxonomy' => 'wptests_tax2' ) );
+		$t5 = $this->factory->term->create( array( 'taxonomy' => 'wptests_tax2', 'parent' => $t4 ) );
+		$t6 = $this->factory->term->create( array( 'taxonomy' => 'wptests_tax2', 'parent' => $t5 ) );
+
+		$p = $this->factory->post->create();
+
+		wp_set_object_terms( $p, $t3, 'wptests_tax1' );
+		wp_set_object_terms( $p, $t6, 'wptests_tax2' );
+
+		$found = get_terms( array( 'wptests_tax1', 'wptests_tax2' ), array(
+			'hierarchical' => true,
+			'hide_empty' => true,
+			'fields' => 'ids',
+		) );
+
+		/*
+		 * Should contain all terms, since they all have non-empty descendants.
+		 * To make the case clearer, test taxonomies separately.
+		 */
+
+		// First taxonomy.
+		$this->assertContains( $t1, $found );
+		$this->assertContains( $t2, $found );
+		$this->assertContains( $t3, $found );
+
+		// Second taxonomy.
+		$this->assertContains( $t4, $found );
+		$this->assertContains( $t5, $found );
+		$this->assertContains( $t6, $found );
+	}
+
 	/**
 	 * @ticket 23261
 	 */