Ticket #57394: patch-with-unit-test.diff

src/wp-includes/user.php

@@ -2123 +2123 @@
                 return new WP_Error( 'user_login_too_long', __( 'Username may not be longer than 60 characters.' ) );
         }
 
+        // Username must be unique.
         if ( ! $update && username_exists( $user_login ) ) {
                 return new WP_Error( 'existing_user_login', __( 'Sorry, that username already exists!' ) );
         }
 
+        // Username must not exist as an existing email.
+        if ( email_exists( $user_login ) ) {
+                return new WP_Error( 'existing_user_login_as_email', __( 'Sorry, that username is not available.' ) );
+        }
+
         /**
          * Filters the list of disallowed usernames.
          *
@@ -3340 +3346 @@
                 $sanitized_user_login = '';
         } elseif ( username_exists( $sanitized_user_login ) ) {
                 $errors->add( 'username_exists', __( '<strong>Error:</strong> This username is already registered. Please choose another one.' ) );
-
+        } elseif ( email_exists( $sanitized_user_login ) ) {
+                $errors->add( 'username_exists_as_email', __( '<strong>Error:</strong> This username is not available. Please choose another one.' ) );
         } else {
                 /** This filter is documented in wp-includes/user.php */
                 $illegal_user_logins = (array) apply_filters( 'illegal_user_logins', array() );

tests/phpunit/tests/user.php

@@ -934 +934 @@
                 $this->assertSame( $expected, $user->user_nicename );
         }
 
+        /**
+         * @ticket 57394
+         */
+        public function test_wp_insert_user_should_reject_username_that_matches_existing_user_email() {
+                $existing_email = get_option( 'admin_email' );
+                $user           = wp_insert_user(
+                        array(
+                                'user_login'    => $existing_email,
+                                'user_email'    => 'whatever@example.com',
+                                'user_pass'     => 'whatever',
+                                'user_nicename' => 'whatever',
+                        )
+                );
+
+                $this->assertWPError( $user );
+                $this->assertSame( 'existing_user_login_as_email', $user->get_error_code() );
+        }
+
         /**
          * @ticket 33793
          */