Ticket #41672: 41672.diff

src/wp-includes/user.php

@@ -1474 +1474 @@
                 return new WP_Error( 'user_login_too_long', __( 'Username may not be longer than 60 characters.' ) );
         }
 
+        $raw_user_email = empty( $userdata['user_email'] ) ? '' : $userdata['user_email'];
+
+        /**
+         * Filters a user's email before the user is created or updated.
+         *
+         * @since 2.0.3
+         *
+         * @param string $raw_user_email The user's email.
+         */
+        $user_email = apply_filters( 'pre_user_email', $raw_user_email );
+
         if ( ! $update && username_exists( $user_login ) ) {
-                return new WP_Error( 'existing_user_login', __( 'Sorry, that username already exists!' ) );
+                if ( email_exists( $user_email ) ) {
+                        return new WP_Error( 'existing_user_email', __( 'Sorry, that email address is already used!' ) );
+                } else {
+                        return new WP_Error( 'existing_user_login', __( 'Sorry, that username already exists!' ) );
+                }
         }
 
         /**
@@ -1529 +1544 @@
          */
         $user_url = apply_filters( 'pre_user_url', $raw_user_url );
 
-        $raw_user_email = empty( $userdata['user_email'] ) ? '' : $userdata['user_email'];
-
-        /**
-         * Filters a user's email before the user is created or updated.
-         *
-         * @since 2.0.3
-         *
-         * @param string $raw_user_email The user's email.
-         */
-        $user_email = apply_filters( 'pre_user_email', $raw_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`