From 2418711c475d3df788b9d1e1b36dbb57602bf64e Mon Sep 17 00:00:00 2001
From: Scott Taylor <wonderboymusic@git.wordpress.org>
Date: Wed, 1 Apr 2015 18:22:16 +0000
Subject: [PATCH] When updating the email address for an existing user, make
 sure the email address is not already in use.

Adds unit tests.

Props rittesh.patel, DrewAPicture.
Fixes #30647.


git-svn-id: https://develop.svn.wordpress.org/trunk@31963 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/user.php     | 10 +++++++++-
 tests/phpunit/tests/user.php | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/src/wp-includes/user.php b/src/wp-includes/user.php
index 3a03ea0425..adb134a148 100644
--- a/src/wp-includes/user.php
+++ b/src/wp-includes/user.php
@@ -1894,7 +1894,15 @@ function wp_insert_user( $userdata ) {
 	 */
 	$user_email = apply_filters( 'pre_user_email', $raw_user_email );
 
-	if ( ! $update && ! defined( 'WP_IMPORTING' ) && email_exists( $user_email ) ) {
+	/*
+	 * If there is no update, just check for `email_exists`. If there is an update,
+	 * check if current email and new email are the same, or not, and check `email_exists`
+	 * accordingly.
+	 */
+	if ( ( ! $update || ( ! empty( $old_user_data ) && $user_email !== $old_user_data->user_email ) )
+		&& ! defined( 'WP_IMPORTING' )
+		&& email_exists( $user_email )
+	) {
 		return new WP_Error( 'existing_user_email', __( 'Sorry, that email address is already used!' ) );
 	}
 	$nickname = empty( $userdata['nickname'] ) ? $user_login : $userdata['nickname'];
diff --git a/tests/phpunit/tests/user.php b/tests/phpunit/tests/user.php
index 8ba4f970d9..43edd3a1cf 100644
--- a/tests/phpunit/tests/user.php
+++ b/tests/phpunit/tests/user.php
@@ -618,6 +618,41 @@ class Tests_User extends WP_UnitTestCase {
 		$this->assertNotContains( 'key', $metas );
 	}
 
+	/**
+	 * @ticket 30647
+	 */
+	function test_user_update_email_error() {
+		$id1 = wp_insert_user( array(
+			'user_login' => rand_str(),
+			'user_pass'  => 'password',
+			'user_email' => 'blackburn@battlefield3.com',
+		) );
+		$this->assertEquals( $id1, email_exists( 'blackburn@battlefield3.com' ) );
+
+		$id2 = wp_insert_user( array(
+			'user_login' => rand_str(),
+			'user_pass'  => 'password',
+			'user_email' => 'miller@battlefield3.com',
+		) );
+		$this->assertEquals( $id2, email_exists( 'miller@battlefield3.com' ) );
+
+		if( ! is_wp_error( $id2 ) ){	
+			$return = wp_update_user( array(
+				'ID'         => $id2,
+				'user_email' => 'david@battlefield3.com',
+			) );
+			$this->assertEquals( $id2, email_exists( 'david@battlefield3.com' ) );
+
+			$return = wp_update_user( array(
+				'ID'         => $id2,
+				'user_email' => 'blackburn@battlefield3.com',
+			) );
+			if ( ! defined( 'WP_IMPORTING' ) ) {
+				$this->assertWPError( $return );
+			}			
+		}
+	}
+
 	/**
 	 * @ticket 29696
 	 */