Changeset 62688

Timestamp:

07/10/2026 05:01:47 PM (2 months ago)

Author:

joedolson

Message:

Users: Improve interfaces for deleting users.

Provide clearer guidance for reassigning or deleting content when deleting users in both single and multisite instances. Content assignment is handled on a per-user basis, rather than forcing all content to be assigned to a single user. Add validation to enforce making a selection. Add fieldsets and legends to improve form structure and accessibility. Move inline JS to common.js. Improve backend logic to process per-user content handling. Exclude users being deleted from dropdown forms.

Developed in ​https://github.com/WordPress/wordpress-develop/pull/10502, ​https://github.com/WordPress/wordpress-develop/pull/12467

Props stefan.velthuys, ocean90, hellofromTonya, akshat2802, hubersen, fakhriaz, ozgursar, sirlouen, realloc, audrasjb, joedolson, afercia, krokodok.
Fixes #56914.

Location:

trunk/src

Files:

• js/_enqueues/admin/common.js (modified) (1 diff)
• wp-admin/css/common.css (modified) (1 diff)
• wp-admin/includes/deprecated.php (modified) (1 diff)
• wp-admin/includes/ms.php (modified) (7 diffs)
• wp-admin/includes/user.php (modified) (1 diff)
• wp-admin/network/users.php (modified) (4 diffs)
• wp-admin/users.php (modified) (8 diffs)

trunk/src/js/_enqueues/admin/common.js

@@ -2357 +2357 @@
         return pub;
 })();
+
+/**
+ * Validate the delete-and-reassign users form and surface an accessible
+ * error summary instead of disabling the submit button.
+ *
+ * Disabled buttons can't be discovered by assistive technology, so rather
+ * than blocking submission we let the form submit, intercept it when content
+ * decisions are still missing, and present a focusable error summary that
+ * lists how many decisions remain and links straight to each one.
+ *
+ * Shared by both the single-site (wp-admin/users.php) and multisite/network
+ * (confirm_delete_users() in wp-admin/includes/ms.php) deletion forms. The two
+ * differ in markup: single site has one content decision per user, multisite
+ * has one decision per site a user belongs to (several radio groups per
+ * fieldset), and their reassign dropdowns use different "no selection" values.
+ * The logic below works per radio group so it covers both.
+ *
+ * @since 7.1.0
+ */
+(function(){
+        const { _n, sprintf } = wp.i18n;
+        const usersForm = document.querySelector( '.delete-and-reassign-users-form' );
+
+        // Check if the form exists and contains any radio buttons.
+        if ( ! usersForm || ! usersForm.querySelector( 'input[type="radio"]' ) ) {
+                return;
+        }
+
+        const summaryId = 'delete-users-error-summary';
+
+        /**
+         * Whether a reassign dropdown has no user selected.
+         *
+         * The "Select a user" placeholder value differs between the forms: the
+         * single-site dropdown uses an empty string, the multisite one uses the
+         * wp_dropdown_users() default of '-1'.
+         *
+         * @param {HTMLSelectElement} select The reassign dropdown.
+         * @return {boolean} True when no real user is selected.
+         */
+        function hasNoSelectedUser( select ) {
+                return '' === select.value || '-1' === select.value;
+        }
+
+        /**
+         * Builds a human-readable label for a radio group's decision.
+         *
+         * Combines the fieldset legend (the user) with the site context that
+         * precedes the group on multisite, so each summary entry is identifiable.
+         *
+         * @param {HTMLElement} group The radio group (<ul>) element.
+         * @return {string} The composed label.
+         */
+        function getDecisionLabel( group ) {
+                const fieldset = group.closest( 'fieldset' );
+                const legend   = fieldset ? fieldset.querySelector( 'legend' ) : null;
+                const parts    = [];
+
+                if ( legend ) {
+                        parts.push( legend.textContent.trim() );
+                }
+
+                // On multisite each radio group is preceded by a "Site: …" paragraph.
+                const previous = group.previousElementSibling;
+                if ( previous && previous !== legend && previous.textContent.trim() ) {
+                        parts.push( previous.textContent.trim() );
+                }
+
+                return parts.join( ' – ' );
+        }
+
+        // Keep the radio selection in sync with the reassign dropdown.
+        usersForm.querySelectorAll( 'select' ).forEach( function( selectElement ) {
+                selectElement.addEventListener( 'change', function( e ) {
+                        const item  = e.target.closest( 'li' );
+                        const radio = item ? item.querySelector( 'input[type="radio"]' ) : null;
+                        if ( radio ) {
+                                radio.checked = ! hasNoSelectedUser( e.target );
+                        }
+                });
+        });
+
+        /**
+         * Returns the radio groups whose content decision is still incomplete.
+         *
+         * A decision unit is a single radio group (<ul>), which maps to one user on
+         * single site and one site-per-user on multisite.
+         *
+         * @return {Array} Objects describing each incomplete decision.
+         */
+        function getIncompleteDecisions() {
+                const incomplete = [];
+
+                usersForm.querySelectorAll( 'fieldset ul' ).forEach( function( group ) {
+                        const radios = group.querySelectorAll( 'input[type="radio"]' );
+                        if ( ! radios.length ) {
+                                return;
+                        }
+
+                        const checked = group.querySelector( 'input[type="radio"]:checked' );
+
+                        // No option chosen yet.
+                        if ( ! checked ) {
+                                incomplete.push( { target: radios[ 0 ], label: getDecisionLabel( group ) } );
+                                return;
+                        }
+
+                        // "Attribute to another user" chosen, but no user selected.
+                        if ( 'reassign' === checked.value ) {
+                                const select = group.querySelector( 'select' );
+                                if ( select && hasNoSelectedUser( select ) ) {
+                                        incomplete.push( { target: select, label: getDecisionLabel( group ) } );
+                                }
+                        }
+                });
+
+                return incomplete;
+        }
+
+        /**
+         * Builds or refreshes the error summary markup.
+         *
+         * @param {Array} incomplete Incomplete decisions from getIncompleteDecisions().
+         * @return {string} The summary title, for announcing to assistive technology.
+         */
+        function renderErrorSummary( incomplete ) {
+                let summary = document.getElementById( summaryId );
+
+                if ( ! summary ) {
+                        summary = document.createElement( 'div' );
+                        summary.id = summaryId;
+                        summary.className = 'notice notice-error';
+                        summary.setAttribute( 'tabindex', '-1' );
+
+                        // The wrapper contains the form on single site and wraps it on
+                        // multisite; insert the summary right after the page heading.
+                        const wrap    = usersForm.querySelector( '.wrap' ) || usersForm.closest( '.wrap' ) || usersForm;
+                        const heading = wrap.querySelector( 'h1' );
+                        wrap.insertBefore( summary, heading ? heading.nextSibling : wrap.firstChild );
+                }
+
+                const count = incomplete.length;
+                const title = sprintf(
+                        /* translators: %s: Number of content decisions still required. */
+                        _n(
+                                '%s content decision is still required before you can delete.',
+                                '%s content decisions are still required before you can delete.',
+                                count
+                        ),
+                        count
+                );
+
+                // Clear any previous markup and invalid states before rebuilding,
+                // so decisions resolved since the last render are no longer flagged.
+                summary.textContent = '';
+                usersForm.querySelectorAll( '[aria-invalid]' ).forEach( function( el ) {
+                        el.removeAttribute( 'aria-invalid' );
+                });
+
+                const titleEl = document.createElement( 'p' );
+                const strong  = document.createElement( 'strong' );
+                strong.textContent = title;
+                titleEl.appendChild( strong );
+                summary.appendChild( titleEl );
+
+                const list = document.createElement( 'ul' );
+                incomplete.forEach( function( item ) {
+                        const li   = document.createElement( 'li' );
+                        const link = document.createElement( 'a' );
+                        link.href        = '#' + item.target.id;
+                        link.textContent = item.label;
+                        link.addEventListener( 'click', function( e ) {
+                                e.preventDefault();
+                                item.target.focus();
+                        });
+                        li.appendChild( link );
+                        list.appendChild( li );
+
+                        item.target.setAttribute( 'aria-invalid', 'true' );
+                });
+                summary.appendChild( list );
+
+                return title;
+        }
+
+        /**
+         * Removes the error summary and clears invalid states.
+         */
+        function clearErrorState() {
+                const summary = document.getElementById( summaryId );
+                if ( summary ) {
+                        summary.remove();
+                }
+                usersForm.querySelectorAll( '[aria-invalid]' ).forEach( function( el ) {
+                        el.removeAttribute( 'aria-invalid' );
+                });
+        }
+
+        /**
+         * Refreshes the error summary to match the current form state.
+         *
+         * @param {boolean} moveFocus Whether to move focus to the summary and
+         *                            announce it (used on a failed submit).
+         * @return {number} The number of incomplete decisions.
+         */
+        function updateSummary( moveFocus ) {
+                const incomplete = getIncompleteDecisions();
+
+                if ( ! incomplete.length ) {
+                        clearErrorState();
+                        return 0;
+                }
+
+                const title = renderErrorSummary( incomplete );
+
+                if ( moveFocus ) {
+                        document.getElementById( summaryId ).focus();
+                        if ( window.wp && window.wp.a11y ) {
+                                window.wp.a11y.speak( title, 'assertive' );
+                        }
+                }
+
+                return incomplete.length;
+        }
+
+        usersForm.addEventListener( 'submit', function( e ) {
+                if ( updateSummary( true ) > 0 ) {
+                        e.preventDefault();
+                }
+        });
+
+        // Keep an existing summary current as decisions are resolved, without
+        // stealing focus on every interaction.
+        usersForm.addEventListener( 'change', function() {
+                if ( document.getElementById( summaryId ) ) {
+                        updateSummary( false );
+                }
+        });
+})();

trunk/src/wp-admin/css/common.css

@@ -2606 +2606 @@
 }
 
+.delete-and-reassign-users-form legend {
+        margin: 1em 0;
+        line-height: 1.5;
+        float: inline-start;
+}
+
+.delete-and-reassign-users-form fieldset > fieldset,
+.delete-and-reassign-users-form fieldset > ul {
+        clear: both;
+}
+
+.delete-and-reassign-users-form fieldset:has(select[aria-invalid="true"]):not(fieldset:has(fieldset)) {
+        border-left: 4px solid #cc1818;
+        background: #fcf0f0;
+        padding-left: 12px;
+}
+
 .importers {
         font-size: 16px;

trunk/src/wp-admin/includes/deprecated.php

@@ -1590 +1590 @@
         return $post;
 }
+
+/**
+ * Was used to add JavaScript to the delete users form.
+ *
+ * @since 3.5.0
+ * @deprecated 7.1.0
+ * @access private
+ */
+function delete_users_add_js() {
+        _deprecated_function( __FUNCTION__, '7.1.0' );
+}

trunk/src/wp-admin/includes/ms.php

@@ -857 +857 @@
  */
 function confirm_delete_users( $users ) {
+        global $wpdb;
+
         $current_user = wp_get_current_user();
         if ( ! is_array( $users ) || empty( $users ) ) {
                 return false;
         }
+
         ?>
-        <h1><?php esc_html_e( 'Users' ); ?></h1>
+        <h1><?php esc_html_e( 'Delete Users' ); ?></h1>
 
         <?php if ( 1 === count( $users ) ) : ?>
@@ -870 +873 @@
         <?php endif; ?>
 
-        <form action="users.php?action=dodelete" method="post">
+        <form action="users.php?action=dodelete" method="post" class="delete-and-reassign-users-form">
         <input type="hidden" name="dodelete" />
         <?php
         wp_nonce_field( 'ms-users-delete' );
         $site_admins = get_super_admins();
-        $admin_out   = '<option value="' . esc_attr( $current_user->ID ) . '">' . $current_user->user_login . '</option>';
         ?>
         <table class="form-table" role="presentation">
         <?php
-        $allusers = (array) $_POST['allusers'];
-        foreach ( $allusers as $user_id ) {
+        foreach ( $users as $user_id ) {
                 if ( '' !== $user_id && '0' !== $user_id ) {
                         $delete_user = get_userdata( $user_id );
@@ -903 +904 @@
                                 );
                         }
+
                         ?>
                         <tr>
@@ -913 +915 @@
                         if ( ! empty( $blogs ) ) {
                                 ?>
-                                <td><fieldset><p><legend>
+                                <td><fieldset><legend>
                                 <?php
                                 printf(
-                                        /* translators: %s: User login. */
-                                        __( 'What should be done with content owned by %s?' ),
-                                        '<em>' . $delete_user->user_login . '</em>'
+                                        /* translators: 1: User login, 2: User ID. */
+                                        __( '%1$s (ID #%2$s): What should be done with the content owned by this user?' ),
+                                        '<strong>' . $delete_user->user_login . '</strong>',
+                                        $user_id
                                 );
                                 ?>
-                                </legend></p>
+                                </legend>
                                 <?php
                                 foreach ( (array) $blogs as $key => $details ) {
@@ -927 +930 @@
                                                 array(
                                                         'blog_id' => $details->userblog_id,
-                                                        'fields'  => array( 'ID', 'user_login' ),
+                                                        'fields'  => array( 'ID' ),
+                                                        'exclude' => $users,
                                                 )
                                         );
 
+                                        $blog_users = wp_list_pluck( $blog_users, 'ID' );
+
                                         if ( is_array( $blog_users ) && ! empty( $blog_users ) ) {
-                                                $user_site     = "<a href='" . esc_url( get_home_url( $details->userblog_id ) ) . "'>{$details->blogname}</a>";
-                                                $user_dropdown = '<label for="reassign_user" class="screen-reader-text">' .
-                                                                /* translators: Hidden accessibility text. */
-                                                                __( 'Select a user' ) .
-                                                        '</label>';
-                                                $user_dropdown .= "<select name='blog[$user_id][$key]' id='reassign_user'>";
-                                                $user_list      = '';
-
-                                                foreach ( $blog_users as $user ) {
-                                                        if ( ! in_array( (int) $user->ID, $allusers, true ) ) {
-                                                                $user_list .= "<option value='{$user->ID}'>{$user->user_login}</option>";
+                                                $user_site = "<a href='" . esc_url( get_home_url( $details->userblog_id ) ) . "'>{$details->blogname}</a>";
+                                                switch_to_blog( $details->userblog_id );
+                                                /* This filter is documented in wp-admin/users.php */
+                                                $user_has_content = (bool) apply_filters( 'users_have_additional_content', false, array( $delete_user->ID ) );
+
+                                                if ( ! $user_has_content ) {
+                                                        if ( $wpdb->get_var(
+                                                                $wpdb->prepare(
+                                                                        "SELECT ID FROM {$wpdb->posts}
+                                                                        WHERE post_author = %d
+                                                                        LIMIT 1",
+                                                                        $delete_user->ID
+                                                                )
+                                                        ) ) {
+                                                                $user_has_content = true;
+                                                        } elseif ( $wpdb->get_var(
+                                                                $wpdb->prepare(
+                                                                        "SELECT link_id FROM {$wpdb->links}
+                                                                        WHERE link_owner = %d
+                                                                        LIMIT 1",
+                                                                        $delete_user->ID
+                                                                )
+                                                        ) ) {
+                                                                $user_has_content = true;
                                                         }
                                                 }
-
-                                                if ( '' === $user_list ) {
-                                                        $user_list = $admin_out;
-                                                }
-
-                                                $user_dropdown .= $user_list;
-                                                $user_dropdown .= "</select>\n";
-                                                ?>
-                                                <ul style="list-style:none;">
-                                                        <li>
+                                                restore_current_blog();
+
+                                                if ( ! $user_has_content ) {
+                                                        ?>
+                                                        <p>
+                                                        <?php
+                                                        /* translators: %s: Link to user's site. */
+                                                        printf( __( 'Site: %s' ), $user_site );
+                                                        ?>
+                                                        </p>
+                                                        <input type="hidden" id="delete_option_<?php echo esc_attr( $details->userblog_id . '_' . $delete_user->ID ); ?>" name="delete[<?php echo $details->userblog_id . '][' . $delete_user->ID; ?>]" value="delete" required />
+                                                        <p><?php _e( 'This user does not have any content.' ); ?></p>
+                                                        <?php
+                                                } else {
+                                                        ?>
+                                                        <fieldset>
+                                                                <legend>
                                                                 <?php
                                                                 /* translators: %s: Link to user's site. */
                                                                 printf( __( 'Site: %s' ), $user_site );
                                                                 ?>
-                                                        </li>
-                                                        <li><label><input type="radio" id="delete_option0" name="delete[<?php echo $details->userblog_id . '][' . $delete_user->ID; ?>]" value="delete" checked="checked" />
-                                                        <?php _e( 'Delete all content.' ); ?></label></li>
-                                                        <li><label><input type="radio" id="delete_option1" name="delete[<?php echo $details->userblog_id . '][' . $delete_user->ID; ?>]" value="reassign" />
-                                                        <?php _e( 'Attribute all content to:' ); ?></label>
-                                                        <?php echo $user_dropdown; ?></li>
-                                                </ul>
-                                                <?php
+                                                                </legend>
+                                                                <ul>
+                                                                        <li>
+                                                                                <input type="radio" id="delete_option_<?php echo esc_attr( $details->userblog_id . '_' . $delete_user->ID ); ?>" name="delete[<?php echo $details->userblog_id . '][' . $delete_user->ID; ?>]" value="delete" required />
+                                                                                <label for="delete_option_<?php echo esc_attr( $details->userblog_id . '_' . $delete_user->ID ); ?>"><?php _e( 'Delete all content.' ); ?></label>
+                                                                        </li>
+                                                                        <li>
+                                                                                <input type="radio" id="reassign_option_<?php echo esc_attr( $details->userblog_id . '_' . $delete_user->ID ); ?>" name="delete[<?php echo $details->userblog_id . '][' . $delete_user->ID; ?>]" value="reassign" required />
+                                                                                <label for="reassign_option_<?php echo esc_attr( $details->userblog_id . '_' . $delete_user->ID ); ?>"><?php _e( 'Attribute all content to another user.' ); ?></label>
+
+                                                                                <label for="reassign_user_<?php echo esc_attr( $details->userblog_id . '_' . $delete_user->ID ); ?>" class="screen-reader-text"><?php _e( 'Select a user to attribute the content to.' ); ?></label>
+                                                                                <?php
+                                                                                wp_dropdown_users(
+                                                                                        array(
+                                                                                                'show_option_none' => __( 'Select a user' ),
+                                                                                                'name'    => "blog[$user_id][$key]",
+                                                                                                'include' => $blog_users,
+                                                                                                'show'    => 'display_name_with_login',
+                                                                                                'id'      => "reassign_user_{$details->userblog_id}_{$delete_user->ID}",
+                                                                                        )
+                                                                                );
+                                                                                ?>
+
+                                                                        </li>
+                                                                </ul>
+                                                        </fieldset>
+                                                        <?php
+                                                }
                                         }
                                 }
@@ -983 +1029 @@
         <?php
         /** This action is documented in wp-admin/users.php */
-        do_action( 'delete_user_form', $current_user, $allusers );
+        do_action( 'delete_user_form', $current_user, $users );
 
         if ( 1 === count( $users ) ) :
@@ -993 +1039 @@
         endif;
 
-        submit_button( __( 'Confirm Deletion' ), 'primary' );
+        submit_button( __( 'Confirm Deletion' ), 'primary', 'submit', false, array( 'id' => 'confirm-users-deletion' ) );
         ?>
         </form>

trunk/src/wp-admin/includes/user.php

@@ -564 +564 @@
 
 /**
- * @since 3.5.0
- * @access private
- */
-function delete_users_add_js() {
-        ?>
-<script>
-jQuery( function($) {
-        var submit = $('#submit').prop('disabled', true);
-        $('input[name="delete_option"]').one('change', function() {
-                submit.prop('disabled', false);
-        });
-        $('#reassign_user').focus( function() {
-                $('#delete_option1').prop('checked', true).trigger('change');
-        });
-} );
-</script>
-        <?php
-}
-
-/**
  * Optional SSL preference that can be turned on by hooking to the 'personal_options' action.
  *

trunk/src/wp-admin/network/users.php

@@ -57 +57 @@
                                 $doaction     = $_POST['action'];
                                 $userfunction = '';
-
-                                foreach ( (array) $_POST['allusers'] as $user_id ) {
+                                $allusers     = (array) $_POST['allusers'];
+
+                                foreach ( $allusers as $user_id ) {
                                         if ( ! empty( $user_id ) ) {
                                                 switch ( $doaction ) {
@@ -73 +74 @@
 
                                                                 echo '<div class="wrap">';
-                                                                confirm_delete_users( $_POST['allusers'] );
+                                                                confirm_delete_users( $allusers );
                                                                 echo '</div>';
 
@@ -189 +190 @@
                         }
 
+                        /*
+                         * Validate that every "reassign" choice has a real target before making
+                         * any changes. The confirmation form blocks this client-side, so this is
+                         * a defense-in-depth guard against an invalid reassignment (e.g. content
+                         * reassigned to the non-existent user "-1") when JavaScript is bypassed.
+                         * Bail out entirely so the deletion is all-or-nothing.
+                         */
+                        if ( ! empty( $_POST['blog'] ) && is_array( $_POST['blog'] ) && ! empty( $_POST['delete'] ) ) {
+                                foreach ( $_POST['blog'] as $id => $blogs ) {
+                                        foreach ( $blogs as $blogid => $reassign_user_id ) {
+                                                if ( isset( $_POST['delete'][ $blogid ][ $id ] )
+                                                        && 'reassign' === $_POST['delete'][ $blogid ][ $id ]
+                                                        && (int) $reassign_user_id < 1
+                                                ) {
+                                                        wp_redirect(
+                                                                add_query_arg(
+                                                                        array( 'error' => 'missing_reassign' ),
+                                                                        network_admin_url( 'users.php' )
+                                                                )
+                                                        );
+                                                        exit;
+                                                }
+                                        }
+                                }
+                        }
+
                         if ( ! empty( $_POST['blog'] ) && is_array( $_POST['blog'] ) ) {
                                 foreach ( $_POST['blog'] as $id => $users ) {
@@ -311 +338 @@
         );
 }
+
+if ( isset( $_REQUEST['error'] ) && 'missing_reassign' === $_REQUEST['error'] ) {
+        wp_admin_notice(
+                __( 'No users were deleted because no user was selected for content reassignment.' ),
+                array(
+                        'type'        => 'error',
+                        'dismissible' => true,
+                        'id'          => 'message',
+                )
+        );
+}
 ?>
 <div class="wrap">

trunk/src/wp-admin/users.php

@@ -214 +214 @@
                         }
 
-                        switch ( $_REQUEST['delete_option'] ) {
+                        if ( 'reassign' === $_REQUEST['delete_option'][ $id ] && empty( $_REQUEST['reassign_user'][ $id ] ) ) {
+                                $update = 'err_missing_reassign';
+                                continue;
+                        }
+
+                        switch ( $_REQUEST['delete_option'][ $id ] ) {
                                 case 'delete':
                                         wp_delete_user( $id );
                                         break;
                                 case 'reassign':
-                                        wp_delete_user( $id, $_REQUEST['reassign_user'] );
+                                        wp_delete_user( $id, $_REQUEST['reassign_user'][ $id ] );
                                         break;
                         }
@@ -307 +312 @@
                 }
 
-                /**
-                 * Filters whether the users being deleted have additional content
-                 * associated with them outside of the `post_author` and `link_owner` relationships.
-                 *
-                 * @since 5.2.0
-                 *
-                 * @param bool  $users_have_additional_content Whether the users have additional content. Default false.
-                 * @param int[] $user_ids                      Array of IDs for users being deleted.
-                 */
-                $users_have_content = (bool) apply_filters( 'users_have_additional_content', false, $user_ids );
-
-                if ( $user_ids && ! $users_have_content ) {
-                        if ( $wpdb->get_var(
-                                "SELECT ID FROM {$wpdb->posts}
-                                WHERE post_author IN( " . implode( ',', $user_ids ) . ' )
-                                LIMIT 1'
-                        ) ) {
-                                $users_have_content = true;
-                        } elseif ( $wpdb->get_var(
-                                "SELECT link_id FROM {$wpdb->links}
-                                WHERE link_owner IN( " . implode( ',', $user_ids ) . ' )
-                                LIMIT 1'
-                        ) ) {
-                                $users_have_content = true;
-                        }
-                }
-
-                if ( $users_have_content ) {
-                        add_action( 'admin_head', 'delete_users_add_js' );
-                }
-
                 require_once ABSPATH . 'wp-admin/admin-header.php';
                 ?>
-                <form method="post" name="updateusers" id="updateusers">
+                <form method="post" name="updateusers" id="updateusers" class="delete-and-reassign-users-form">
                 <?php wp_nonce_field( 'delete-users' ); ?>
                 <?php echo $referer; ?>
@@ -366 +340 @@
                 <ul>
                 <?php
-                $go_delete = 0;
+                $go_delete          = 0;
+                $users_have_content = false;
 
                 foreach ( $all_user_ids as $id ) {
@@ -386 +361 @@
                                         esc_attr( $id )
                                 );
-                                printf(
-                                        /* translators: 1: User ID, 2: User login. */
-                                        __( 'ID #%1$s: %2$s' ),
-                                        $id,
-                                        $user->user_login
-                                );
+
+                                /**
+                                 * Filters whether the users being deleted have additional content
+                                 * associated with them outside of the `post_author` and `link_owner` relationships.
+                                 *
+                                 * @since 5.2.0
+                                 *
+                                 * @param bool  $users_have_additional_content Whether the users have additional content. Default false.
+                                 * @param int[] $user_ids                      Array of IDs for users being deleted.
+                                 */
+                                $user_has_content = (bool) apply_filters( 'users_have_additional_content', false, array( $id ) );
+
+                                if ( ! $user_has_content ) {
+                                        if ( $wpdb->get_var(
+                                                $wpdb->prepare(
+                                                        "SELECT ID FROM {$wpdb->posts}
+                                                        WHERE post_author = %d
+                                                        LIMIT 1",
+                                                        $id
+                                                )
+                                        ) ) {
+                                                $user_has_content = true;
+                                        } elseif ( $wpdb->get_var(
+                                                $wpdb->prepare(
+                                                        "SELECT link_id FROM {$wpdb->links}
+                                                        WHERE link_owner = %d
+                                                        LIMIT 1",
+                                                        $id
+                                                )
+                                        ) ) {
+                                                $user_has_content = true;
+                                        }
+                                }
+
+                                if ( ! $user_has_content ) {
+                                        ?>
+                                        <input type="hidden" name="delete_option[<?php echo esc_attr( $id ); ?>]" value="delete" required />
+                                        <p>
+                                        <?php
+                                        printf(
+                                                /* translators: 1: User login. 2: User ID */
+                                                __( '%1$s (ID #%2$s): This user does not have any content.' ),
+                                                '<strong>' . $user->user_login . '</strong>',
+                                                $id
+                                        );
+                                        ?>
+                                        </p>
+                                        <?php
+                                } else {
+                                        ?>
+                                        <fieldset>
+                                        <legend>
+                                        <?php
+                                        printf(
+                                                /* translators: 1: User login, 2: User ID. */
+                                                __( '%1$s (ID #%2$s): What should be done with the content owned by this user?' ),
+                                                '<strong>' . $user->user_login . '</strong>',
+                                                $id
+                                        );
+                                        ?>
+                                        </legend>
+
+                                        <ul>
+                                                <li>
+                                                        <input type="radio" id="delete_option_<?php echo esc_attr( $id ); ?>" name="delete_option[<?php echo esc_attr( $id ); ?>]" value="delete" required />
+                                                        <label for="delete_option_<?php echo esc_attr( $id ); ?>"><?php _e( 'Delete all content.' ); ?></label>
+                                                </li>
+                                                <li>
+                                                        <input type="radio" id="reassign_option_<?php echo esc_attr( $id ); ?>" name="delete_option[<?php echo esc_attr( $id ); ?>]" value="reassign" required />
+                                                        <label for="reassign_option_<?php echo esc_attr( $id ); ?>"><?php _e( 'Attribute all content to another user.' ); ?></label>
+
+                                                        <label for="reassign_user_<?php echo esc_attr( $id ); ?>" class="screen-reader-text"><?php _e( 'Select a user to attribute the content to.' ); ?></label>
+                                                        <?php
+                                                        wp_dropdown_users(
+                                                                array(
+                                                                        'show_option_none'  => __( 'Select a user' ),
+                                                                        'option_none_value' => '',
+                                                                        'name'              => 'reassign_user[' . $id . ']',
+                                                                        'id'                => 'reassign_user_' . $id,
+                                                                        'exclude'           => $user_ids,
+                                                                        'show'              => 'display_name_with_login',
+                                                                )
+                                                        );
+                                                        ?>
+                                                </li>
+                                        </ul>
+                                        </fieldset>
+                                        <?php
+                                        $users_have_content = true;
+                                }
+
                                 echo "</li>\n";
 
@@ -402 +462 @@
                 <?php
                 if ( $go_delete ) :
-
-                        if ( ! $users_have_content ) :
-                                ?>
-                                <input type="hidden" name="delete_option" value="delete" />
-                        <?php else : ?>
-                                <fieldset>
-                                <?php if ( 1 === $go_delete ) : ?>
-                                        <p><legend><?php _e( 'What should be done with content owned by this user?' ); ?></legend></p>
-                                <?php else : ?>
-                                        <p><legend><?php _e( 'What should be done with content owned by these users?' ); ?></legend></p>
-                                <?php endif; ?>
-
-                                <ul style="list-style:none;">
-                                        <li>
-                                                <input type="radio" id="delete_option0" name="delete_option" value="delete" />
-                                                <label for="delete_option0"><?php _e( 'Delete all content.' ); ?></label>
-                                        </li>
-                                        <li>
-                                                <input type="radio" id="delete_option1" name="delete_option" value="reassign" />
-                                                <label for="delete_option1"><?php _e( 'Attribute all content to:' ); ?></label>
-                                                <?php
-                                                wp_dropdown_users(
-                                                        array(
-                                                                'name'    => 'reassign_user',
-                                                                'exclude' => $user_ids,
-                                                                'show'    => 'display_name_with_login',
-                                                        )
-                                                );
-                                                ?>
-                                        </li>
-                                </ul>
-                                </fieldset>
-                                <?php
-                        endif;
-
                         /**
                          * Fires at the end of the delete users form prior to the confirm button.
@@ -613 +638 @@
                 $messages = array();
                 if ( isset( $_GET['update'] ) ) :
+                        $delete_count = isset( $_GET['delete_count'] ) ? (int) $_GET['delete_count'] : 0;
+
                         switch ( $_GET['update'] ) {
                                 case 'del':
                                 case 'del_many':
-                                        $delete_count = isset( $_GET['delete_count'] ) ? (int) $_GET['delete_count'] : 0;
                                         if ( 1 === $delete_count ) {
                                                 $message = __( 'User deleted.' );
@@ -696 +722 @@
                                                 )
                                         );
-                                        $messages[] = wp_get_admin_notice(
-                                                __( 'Other user roles have been changed.' ),
-                                                array(
-                                                        'id'                 => 'message',
-                                                        'additional_classes' => array( 'updated' ),
-                                                        'dismissible'        => true,
-                                                )
-                                        );
+                                        if ( $delete_count > 0 ) {
+                                                $messages[] = wp_get_admin_notice(
+                                                        __( 'Other user roles have been changed.' ),
+                                                        array(
+                                                                'id'                 => 'message',
+                                                                'additional_classes' => array( 'updated' ),
+                                                                'dismissible'        => true,
+                                                        )
+                                                );
+                                        }
                                         break;
                                 case 'err_admin_del':
@@ -714 +742 @@
                                                 )
                                         );
-                                        $messages[] = wp_get_admin_notice(
-                                                __( 'Other users have been deleted.' ),
-                                                array(
-                                                        'id'                 => 'message',
-                                                        'additional_classes' => array( 'updated' ),
-                                                        'dismissible'        => true,
-                                                )
-                                        );
+                                        if ( $delete_count > 0 ) {
+                                                $messages[] = wp_get_admin_notice(
+                                                        __( 'Other users have been deleted.' ),
+                                                        array(
+                                                                'id'                 => 'message',
+                                                                'additional_classes' => array( 'updated' ),
+                                                                'dismissible'        => true,
+                                                        )
+                                                );
+                                        }
+                                        break;
+                                case 'err_missing_reassign':
+                                        $messages[] = wp_get_admin_notice(
+                                                __( 'Users could not be deleted because no user was selected for content reassignment.' ),
+                                                array(
+                                                        'id'                 => 'message',
+                                                        'additional_classes' => array( 'error' ),
+                                                        'dismissible'        => true,
+                                                )
+                                        );
+                                        if ( $delete_count > 0 ) {
+                                                $messages[] = wp_get_admin_notice(
+                                                        __( 'Other users have been deleted.' ),
+                                                        array(
+                                                                'id'                 => 'message',
+                                                                'additional_classes' => array( 'updated' ),
+                                                                'dismissible'        => true,
+                                                        )
+                                                );
+                                        }
                                         break;
                                 case 'remove':