From e8c7634e792b177fabec83079606fb1143cf3dc7 Mon Sep 17 00:00:00 2001
From: Scott Taylor <wonderboymusic@git.wordpress.org>
Date: Thu, 5 Sep 2013 17:14:54 +0000
Subject: [PATCH] Avoid database error when `include` or `exclude` is not
 really a `term_id`. Adds more unit tests.

Props kovshenin.
Fixes #11823.



git-svn-id: https://develop.svn.wordpress.org/trunk@25257 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/taxonomy.php          |  9 ++++++---
 tests/phpunit/tests/term/getTerms.php | 15 +++++++++++++--
 2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/src/wp-includes/taxonomy.php b/src/wp-includes/taxonomy.php
index c5af198cc7..fa32393b45 100644
--- a/src/wp-includes/taxonomy.php
+++ b/src/wp-includes/taxonomy.php
@@ -1310,9 +1310,10 @@ function get_terms($taxonomies, $args = '') {
 		$inclusions = implode( ',', wp_parse_id_list( $include ) );
 	}
 
-	if ( ! empty( $inclusions ) )
+	if ( ! empty( $inclusions ) ) {
 		$inclusions = ' AND t.term_id IN ( ' . $inclusions . ' )';
-	$where .= $inclusions;
+		$where .= $inclusions;
+	}
 
 	$exclusions = '';
 	if ( ! empty( $exclude_tree ) ) {
@@ -1339,7 +1340,9 @@ function get_terms($taxonomies, $args = '') {
 		$exclusions = ' AND t.term_id NOT IN (' . $exclusions . ')';
 
 	$exclusions = apply_filters( 'list_terms_exclusions', $exclusions, $args );
-	$where .= $exclusions;
+
+	if ( ! empty( $exclusions ) )
+		$where .= $exclusions;
 
 	if ( !empty($slug) ) {
 		$slug = sanitize_title($slug);
diff --git a/tests/phpunit/tests/term/getTerms.php b/tests/phpunit/tests/term/getTerms.php
index aec88e462c..05f771f70c 100644
--- a/tests/phpunit/tests/term/getTerms.php
+++ b/tests/phpunit/tests/term/getTerms.php
@@ -121,10 +121,11 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 	}
 
  	/**
-	 * @ti
-	 * cket 11823
+	 * @ticket 11823
  	 */
 	function test_get_terms_include_exclude() {
+		global $wpdb;
+
 		$term_id1 = $this->factory->tag->create();
 		$term_id2 = $this->factory->tag->create();
 		$inc_terms = get_terms( 'post_tag', array(
@@ -138,6 +139,16 @@ class Tests_Term_getTerms extends WP_UnitTestCase {
 			'hide_empty' => false
 		) );
 		$this->assertEquals( array(), wp_list_pluck( $exc_terms, 'term_id' ) );
+
+		// These should not generate query errors.
+		get_terms( 'post_tag', array( 'exclude' => array( 0 ), 'hide_empty' => false ) );
+		$this->assertEmpty( $wpdb->last_error );
+
+		get_terms( 'post_tag', array( 'exclude' => array( 'unexpected-string' ), 'hide_empty' => false ) );
+		$this->assertEmpty( $wpdb->last_error );
+
+		get_terms( 'post_tag', array( 'include' => array( 'unexpected-string' ), 'hide_empty' => false ) );
+		$this->assertEmpty( $wpdb->last_error );
 	}
 
 	/**