From 3b6ff031365b3ab34951682c8a63a4a102190901 Mon Sep 17 00:00:00 2001
From: Sergey Biryukov <sergeybiryukov@git.wordpress.org>
Date: Mon, 13 Apr 2015 01:20:57 +0000
Subject: [PATCH] `wp_update_term()` should check if `get_term()` returned
 null.

props dlh.
fixes #31954.

git-svn-id: https://develop.svn.wordpress.org/trunk@32117 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/taxonomy.php              | 14 ++++++++++----
 tests/phpunit/tests/term/wpUpdateTerm.php | 12 ++++++++++++
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/src/wp-includes/taxonomy.php b/src/wp-includes/taxonomy.php
index c1c3f99679..cce486786b 100644
--- a/src/wp-includes/taxonomy.php
+++ b/src/wp-includes/taxonomy.php
@@ -3365,16 +3365,22 @@ function wp_unique_term_slug($slug, $term) {
 function wp_update_term( $term_id, $taxonomy, $args = array() ) {
 	global $wpdb;
 
-	if ( ! taxonomy_exists($taxonomy) )
-		return new WP_Error('invalid_taxonomy', __('Invalid taxonomy'));
+	if ( ! taxonomy_exists( $taxonomy ) ) {
+		return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy' ) );
+	}
 
 	$term_id = (int) $term_id;
 
 	// First, get all of the original args
-	$term = get_term ($term_id, $taxonomy, ARRAY_A);
+	$term = get_term( $term_id, $taxonomy, ARRAY_A );
 
-	if ( is_wp_error( $term ) )
+	if ( is_wp_error( $term ) ) {
 		return $term;
+	}
+
+	if ( ! $term ) {
+		return new WP_Error( 'invalid_term', __( 'Empty Term' ) );
+	}
 
 	// Escape data pulled from DB.
 	$term = wp_slash($term);
diff --git a/tests/phpunit/tests/term/wpUpdateTerm.php b/tests/phpunit/tests/term/wpUpdateTerm.php
index 33d579b89c..b00bd67ffe 100644
--- a/tests/phpunit/tests/term/wpUpdateTerm.php
+++ b/tests/phpunit/tests/term/wpUpdateTerm.php
@@ -653,4 +653,16 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 
 		_unregister_taxonomy( 'wptests_tax' );
 	}
+
+	/**
+	 * @ticket 31954
+	 */
+	public function test_wp_update_term_with_null_get_term() {
+		$t = $this->factory->term->create( array( 'taxonomy' => 'category' ) );
+		$found = wp_update_term( $t, 'post_tag', array( 'slug' => 'foo' ) );
+
+		$this->assertWPError( $found );
+		$this->assertSame( 'invalid_term', $found->get_error_code() );
+	}
+
 }