Ticket #24048: 24048.10.diff

src/wp-admin/css/common.css

@@ -1466 +1466 @@
 .wrap #templateside .notice {
         display: block;
         margin: 0;
-        padding: 5px 12px;
+        padding: 5px 8px;
         font-weight: 600;
         text-decoration: none;
 }
 
 .wrap #templateside span.notice {
-  margin-left: -12px;
+        margin-left: -12px;
 }
 
 #templateside li.notice a {
-  padding: 0;
+        padding: 0;
 }
 
 /* Update icon. */
@@ -3036 +3036 @@
         width: 97%;
         height: calc( 100vh - 280px );
 }
+
 #templateside {
         margin-top: 31px;
-        overflow: scroll;
+        overflow: auto;
+        padding: 2px;
+        height: calc(100vh - 280px);
+}
+#templateside ul ul {
+        padding-left: 12px;
+}
+
+/*
+ * Styles for Theme and Plugin editors.
+ */
+
+/* Hide collapsed items. */
+[role="treeitem"][aria-expanded="false"] > ul {
+        display: none;
 }
 
+/* Use arrow dashicons for folder states, but hide from screen readers. */
+[role="treeitem"] span[aria-hidden] {
+        display: inline;
+        font-family: dashicons;
+        font-size: 20px;
+        position: absolute;
+        pointer-events: none;
+}
+[role="treeitem"][aria-expanded="false"] > .folder-label .icon:after {
+        content: "\f139";
+}
+[role="treeitem"][aria-expanded="true"] > .folder-label .icon:after {
+        content: "\f140";
+}
+[role="treeitem"] .folder-label {
+        display: block;
+        padding: 3px 3px 3px 12px;
+        cursor: pointer;
+}
+
+/* Remove outline, and create our own focus and hover styles */
+[role="treeitem"] {
+        outline: 0;
+}
+[role="treeitem"] .folder-label.focus {
+        color: #124964;
+        box-shadow: 0 0 0 1px #5b9dd9, 0 0 2px 1px rgba(30, 140, 190, .8);
+}
+[role="treeitem"].hover,
+[role="treeitem"] .folder-label.hover {
+        background-color: #DDDDDD;
+}
+
+.tree-folder {
+        margin: 0;
+        position: relative;
+}
+[role="treeitem"] li {
+        position: relative;
+}
+
+/* Styles for folder indicators/depth */
+.tree-folder .tree-folder::after {
+        content: ' ';
+        display: block;
+        position: absolute;
+        left: 2px;
+        border-left: 1px solid #ccc;
+        top: -13px;
+        bottom: 10px;
+}
+.tree-folder > li::before {
+        content: ' ';
+        position: absolute;
+        display: block;
+        border-left: 1px solid #ccc;
+        left: 2px;
+        top: -5px;
+        height: 18px;
+        width: 7px;
+        border-bottom: 1px solid #ccc;
+}
+.tree-folder > li::after {
+        content: ' ';
+        position: absolute;
+        display: block;
+        border-left: 1px solid #ccc;
+        left: 2px;
+        bottom: -7px;
+        top: 0;
+}
+
+/* current-file needs to adjustment for .notice styles */
+#templateside .current-file {
+        margin: -4px 0 -2px;
+}
+.tree-folder > .current-file::before {
+        left: 4px;
+        height: 15px;
+        width: 6px;
+        border-left: none;
+        top: 3px;
+}
+.tree-folder > .current-file::after {
+        bottom: -4px;
+        height: 7px;
+        left: 2px;
+        top: auto;
+}
+
+/* Lines shouldn't continue on last item */
+.tree-folder > li:last-child::after,
+.tree-folder li:last-child > .tree-folder::after {
+        display: none;
+}
+
+
 #theme-plugin-editor-label {
         display: inline-block;
         margin-bottom: 1em;
@@ -3653 +3765 @@
                 width: 100%;
         }
 
+        #templateside ul ul {
+                padding-left: 1.5em;
+        }
+        [role="treeitem"] .folder-label {
+                display: block;
+                padding: 5px;
+        }
+        .tree-folder > li::before,
+        .tree-folder > li::after,
+        .tree-folder .tree-folder::after {
+                left: -8px;
+        }
+        .tree-folder > li::before {
+                top: 0px;
+                height: 13px;
+        }
+        .tree-folder > .current-file::before {
+                left: -5px;
+                top: 7px;
+                width: 4px;
+        }
+        .tree-folder > .current-file::after {
+                height: 9px;
+                left: -8px;
+        }
+        .wrap #templateside span.notice {
+                margin-left: -14px;
+        }
+
         .fileedit-sub .alignright {
                 margin-top: 15px;
         }

src/wp-admin/includes/misc.php

@@ -269 +269 @@
         update_option( 'recently_edited', $oldfiles );
 }
 
+/**
+ * Makes a tree structure for the Theme Editor's file list.
+ *
+ * @since 4.9.0
+ * @access private
+ *
+ * @param array $allowed_files List of theme file paths.
+ * @return array Tree structure for listing theme files.
+ */
+function wp_make_theme_file_tree( $allowed_files ) {
+        $tree_list = array();
+        foreach ( $allowed_files as $file_name => $absolute_filename ) {
+                $list = explode( '/', $file_name );
+                $last_dir = &$tree_list;
+                foreach ( $list as $dir ) {
+                        $last_dir =& $last_dir[ $dir ];
+                }
+                $last_dir = $file_name;
+        }
+        return $tree_list;
+}
+
+/**
+ * Outputs the formatted file list for the Theme Editor.
+ *
+ * @since 4.9.0
+ * @access private
+ *
+ * @param array|string $tree  List of file/folder paths, or filename.
+ * @param int          $level The aria-level for the current iteration.
+ * @param int          $size  The aria-setsize for the current iteration.
+ * @param int          $index The aria-posinset for the current iteration.
+ */
+function wp_print_theme_file_tree( $tree, $level = 2, $size = 1, $index = 1 ) {
+        global $relative_file, $stylesheet;
+
+        if ( is_array( $tree ) ) {
+                $index = 0;
+                $size = count( $tree );
+                foreach ( $tree as $label => $theme_file ) :
+                        $index++;
+                        if ( ! is_array( $theme_file ) ) {
+                                wp_print_theme_file_tree( $theme_file, $level, $index, $size );
+                                continue;
+                        }
+                        ?>
+                        <li role="treeitem" aria-expanded="true" tabindex="-1"
+                                aria-level="<?php echo esc_attr( $level ); ?>"
+                                aria-setsize="<?php echo esc_attr( $size ); ?>"
+                                aria-posinset="<?php echo esc_attr( $index ); ?>">
+                                <span class="folder-label"><?php echo esc_html( $label ); ?> <span class="screen-reader-text"><?php _e( 'folder' ); ?></span><span aria-hidden="true" class="icon"></span></span>
+                                <ul role="group" class="tree-folder"><?php wp_print_theme_file_tree( $theme_file, $level + 1, $index, $size ); ?></ul>
+                        </li>
+                        <?php
+                endforeach;
+        } else {
+                $filename = $tree;
+                $url = add_query_arg(
+                        array(
+                                'file' => rawurlencode( $tree ),
+                                'theme' => rawurlencode( $stylesheet ),
+                        ),
+                        admin_url( 'theme-editor.php' )
+                );
+                ?>
+                <li role="none" class="<?php echo esc_attr( $relative_file === $filename ? 'current-file' : '' ); ?>">
+                        <a role="treeitem" tabindex="<?php echo esc_attr( $relative_file === $filename ? '0' : '-1' ); ?>"
+                                href="<?php echo esc_url( $url ); ?>"
+                                aria-level="<?php echo esc_attr( $level ); ?>"
+                                aria-setsize="<?php echo esc_attr( $size ); ?>"
+                                aria-posinset="<?php echo esc_attr( $index ); ?>">
+                                <?php
+                                $file_description = esc_html( get_file_description( $filename ) );
+                                if ( $file_description !== $filename && basename( $filename ) !== $file_description ) {
+                                        $file_description .= '<br /><span class="nonessential">(' . esc_html( $filename ) . ')</span>';
+                                }
+
+                                if ( $relative_file === $filename ) {
+                                        echo '<span class="notice notice-info">' . $file_description . '</span>';
+                                } else {
+                                        echo $file_description;
+                                }
+                                ?>
+                        </a>
+                </li>
+                <?php
+        }
+}
+
+/**
+ * Makes a tree structure for the Plugin Editor's file list.
+ *
+ * @since 4.9.0
+ * @access private
+ *
+ * @param string $plugin_editable_files List of plugin file paths.
+ *
+ * @return array Tree structure for listing plugin files.
+ */
+function wp_make_plugin_file_tree( $plugin_editable_files ) {
+        $tree_list = array();
+        foreach ( $plugin_editable_files as $plugin_file ) {
+                $list = explode( '/', preg_replace( '#^.+?/#', '', $plugin_file ) );
+                $last_dir = &$tree_list;
+                foreach ( $list as $dir ) {
+                        $last_dir =& $last_dir[ $dir ];
+                }
+                $last_dir = $plugin_file;
+        }
+        return $tree_list;
+}
+
+/**
+ * Outputs the formatted file list for the Plugin Editor.
+ *
+ * @since 4.9.0
+ * @access private
+ *
+ * @param array|string $tree  List of file/folder paths, or filename.
+ * @param string       $label Name of file or folder to print.
+ * @param int          $level The aria-level for the current iteration.
+ * @param int          $size  The aria-setsize for the current iteration.
+ * @param int          $index The aria-posinset for the current iteration.
+ */
+function wp_print_plugin_file_tree( $tree, $label = '', $level = 2, $size = 1, $index = 1 ) {
+        global $file, $plugin;
+        if ( is_array( $tree ) ) {
+                $index = 0;
+                $size = count( $tree );
+                foreach ( $tree as $label => $plugin_file ) :
+                        $index++;
+                        if ( ! is_array( $plugin_file ) ) {
+                                wp_print_plugin_file_tree( $plugin_file, $label, $level, $index, $size );
+                                continue;
+                        }
+                        ?>
+                        <li role="treeitem" aria-expanded="true" tabindex="-1"
+                                aria-level="<?php echo esc_attr( $level ); ?>"
+                                aria-setsize="<?php echo esc_attr( $size ); ?>"
+                                aria-posinset="<?php echo esc_attr( $index ); ?>">
+                                <span class="folder-label"><?php echo esc_html( $label ); ?> <span class="screen-reader-text"><?php _e( 'folder' ); ?></span><span aria-hidden="true" class="icon"></span></span>
+                                <ul role="group" class="tree-folder"><?php wp_print_plugin_file_tree( $plugin_file, '', $level + 1, $index, $size ); ?></ul>
+                        </li>
+                        <?php
+                endforeach;
+        } else {
+                $url = add_query_arg(
+                        array(
+                                'file' => rawurlencode( $tree ),
+                                'plugin' => rawurlencode( $plugin ),
+                        ),
+                        admin_url( 'plugin-editor.php' )
+                );
+                ?>
+                <li role="none" class="<?php echo esc_attr( $file === $tree ? 'current-file' : '' ); ?>">
+                        <a role="treeitem" tabindex="<?php echo esc_attr( $file === $tree ? '0' : '-1' ); ?>"
+                                href="<?php echo esc_url( $url ); ?>"
+                                aria-level="<?php echo esc_attr( $level ); ?>"
+                                aria-setsize="<?php echo esc_attr( $size ); ?>"
+                                aria-posinset="<?php echo esc_attr( $index ); ?>">
+                                <?php
+                                if ( $file === $tree ) {
+                                        echo '<span class="notice notice-info">' . esc_html( $label ) . '</span>';
+                                } else {
+                                        echo esc_html( $label );
+                                }
+                                ?>
+                        </a>
+                </li>
+                <?php
+        }
+}
+
 /**
  * Flushes rewrite rules if siteurl, home or page_on_front changed.
  *

src/wp-admin/js/theme-plugin-editor.js

@@ -6 +6 @@
 
 wp.themePluginEditor = (function( $ ) {
         'use strict';
+        var component, TreeLinks;
 
-        var component = {
+        component = {
                 l10n: {
                         lintError: {
                                 singular: '',
@@ -66 +67 @@
                         } );
                 }
 
+                $( component.initFileBrowser );
+
                 $( window ).on( 'beforeunload', function() {
                         if ( component.dirty ) {
                                 return component.l10n.saveAlert;
@@ -86 +89 @@
                         pointer: component.themeOrPlugin + '_editor_notice'
                 });
 
-                // hide modal
+                // Hide modal.
                 component.warning.remove();
                 $( 'body' ).removeClass( 'modal-open' );
 
-                // return focus - is this a trap?
+                // Return focus - is this a trap?
                 component.instance.codemirror.focus();
         };
 
@@ -148 +151 @@
                         component.removeNotice( component.lastSaveNoticeCode );
                 }
 
-                request.done( function ( response ) {
+                request.done( function( response ) {
                         component.lastSaveNoticeCode = 'file_saved';
                         component.addNotice({
                                 code: component.lastSaveNoticeCode,
@@ -159 +162 @@
                         component.dirty = false;
                 } );
 
-                request.fail( function ( response ) {
+                request.fail( function( response ) {
                         var notice = $.extend(
                                 {
                                         code: 'save_error',
@@ -350 +353 @@
                 component.instance = editor;
         };
 
+        /**
+         * Initialization of the file browser's folder states.
+         *
+         * @since 4.9.0
+         * @returns {void}
+         */
+        component.initFileBrowser = function initFileBrowser() {
+
+                // Collapse all folders.
+                $( '#templateside [role="group"]' ).parent().attr( 'aria-expanded', false );
+
+                // Expand ancestors to the current file.
+                $( '#templateside .notice' ).parents( '[aria-expanded]' ).attr( 'aria-expanded', true );
+
+                // Find Tree elements and enhance them.
+                $( '#templateside [role="tree"]' ).each( function() {
+                        var treeLinks = new TreeLinks( this );
+                        treeLinks.init();
+                } );
+        };
+
+        /* jshint ignore:start */
+        /* jscs:disable */
+        /* eslint-disable */
+
+        /**
+         * Creates a new TreeitemLink.
+         *
+         * @since 4.9.0
+         * @class
+         * @private
+         * @see {@link https://www.w3.org/TR/wai-aria-practices-1.1/examples/treeview/treeview-2/treeview-2b.html|W3C Treeview Example}
+         * @license W3C-20150513
+         */
+        var TreeitemLink = (function () {
+                /**
+                 *   This content is licensed according to the W3C Software License at
+                 *   https://www.w3.org/Consortium/Legal/2015/copyright-software-and-document
+                 *
+                 *   File:   TreeitemLink.js
+                 *
+                 *   Desc:   Treeitem widget that implements ARIA Authoring Practices
+                 *           for a tree being used as a file viewer
+                 *
+                 *   Author: Jon Gunderson, Ku Ja Eun and Nicholas Hoyt
+                 */
+
+                /**
+                 *   @constructor
+                 *
+                 *   @desc
+                 *       Treeitem object for representing the state and user interactions for a
+                 *       treeItem widget
+                 *
+                 *   @param node
+                 *       An element with the role=tree attribute
+                 */
+
+                var TreeitemLink = function (node, treeObj, group) {
+
+                        // Check whether node is a DOM element
+                        if (typeof node !== 'object') {
+                                return;
+                        }
+
+                        node.tabIndex = -1;
+                        this.tree = treeObj;
+                        this.groupTreeitem = group;
+                        this.domNode = node;
+                        this.label = node.textContent.trim();
+                        this.stopDefaultClick = false;
+
+                        if (node.getAttribute('aria-label')) {
+                                this.label = node.getAttribute('aria-label').trim();
+                        }
+
+                        this.isExpandable = false;
+                        this.isVisible = false;
+                        this.inGroup = false;
+
+                        if (group) {
+                                this.inGroup = true;
+                        }
+
+                        var elem = node.firstElementChild;
+
+                        while (elem) {
+
+                                if (elem.tagName.toLowerCase() == 'ul') {
+                                        elem.setAttribute('role', 'group');
+                                        this.isExpandable = true;
+                                        break;
+                                }
+
+                                elem = elem.nextElementSibling;
+                        }
+
+                        this.keyCode = Object.freeze({
+                                RETURN: 13,
+                                SPACE: 32,
+                                PAGEUP: 33,
+                                PAGEDOWN: 34,
+                                END: 35,
+                                HOME: 36,
+                                LEFT: 37,
+                                UP: 38,
+                                RIGHT: 39,
+                                DOWN: 40
+                        });
+                };
+
+                TreeitemLink.prototype.init = function () {
+                        this.domNode.tabIndex = -1;
+
+                        if (!this.domNode.getAttribute('role')) {
+                                this.domNode.setAttribute('role', 'treeitem');
+                        }
+
+                        this.domNode.addEventListener('keydown', this.handleKeydown.bind(this));
+                        this.domNode.addEventListener('click', this.handleClick.bind(this));
+                        this.domNode.addEventListener('focus', this.handleFocus.bind(this));
+                        this.domNode.addEventListener('blur', this.handleBlur.bind(this));
+
+                        if (this.isExpandable) {
+                                this.domNode.firstElementChild.addEventListener('mouseover', this.handleMouseOver.bind(this));
+                                this.domNode.firstElementChild.addEventListener('mouseout', this.handleMouseOut.bind(this));
+                        }
+                        else {
+                                this.domNode.addEventListener('mouseover', this.handleMouseOver.bind(this));
+                                this.domNode.addEventListener('mouseout', this.handleMouseOut.bind(this));
+                        }
+                };
+
+                TreeitemLink.prototype.isExpanded = function () {
+
+                        if (this.isExpandable) {
+                                return this.domNode.getAttribute('aria-expanded') === 'true';
+                        }
+
+                        return false;
+
+                };
+
+                /* EVENT HANDLERS */
+
+                TreeitemLink.prototype.handleKeydown = function (event) {
+                        var tgt = event.currentTarget,
+                                flag = false,
+                                _char = event.key,
+                                clickEvent;
+
+                        function isPrintableCharacter(str) {
+                                return str.length === 1 && str.match(/\S/);
+                        }
+
+                        function printableCharacter(item) {
+                                if (_char == '*') {
+                                        item.tree.expandAllSiblingItems(item);
+                                        flag = true;
+                                }
+                                else {
+                                        if (isPrintableCharacter(_char)) {
+                                                item.tree.setFocusByFirstCharacter(item, _char);
+                                                flag = true;
+                                        }
+                                }
+                        }
+
+                        this.stopDefaultClick = false;
+
+                        if (event.altKey || event.ctrlKey || event.metaKey) {
+                                return;
+                        }
+
+                        if (event.shift) {
+                                if (event.keyCode == this.keyCode.SPACE || event.keyCode == this.keyCode.RETURN) {
+                                        event.stopPropagation();
+                                        this.stopDefaultClick = true;
+                                }
+                                else {
+                                        if (isPrintableCharacter(_char)) {
+                                                printableCharacter(this);
+                                        }
+                                }
+                        }
+                        else {
+                                switch (event.keyCode) {
+                                        case this.keyCode.SPACE:
+                                        case this.keyCode.RETURN:
+                                                if (this.isExpandable) {
+                                                        if (this.isExpanded()) {
+                                                                this.tree.collapseTreeitem(this);
+                                                        }
+                                                        else {
+                                                                this.tree.expandTreeitem(this);
+                                                        }
+                                                        flag = true;
+                                                }
+                                                else {
+                                                        event.stopPropagation();
+                                                        this.stopDefaultClick = true;
+                                                }
+                                                break;
+
+                                        case this.keyCode.UP:
+                                                this.tree.setFocusToPreviousItem(this);
+                                                flag = true;
+                                                break;
+
+                                        case this.keyCode.DOWN:
+                                                this.tree.setFocusToNextItem(this);
+                                                flag = true;
+                                                break;
+
+                                        case this.keyCode.RIGHT:
+                                                if (this.isExpandable) {
+                                                        if (this.isExpanded()) {
+                                                                this.tree.setFocusToNextItem(this);
+                                                        }
+                                                        else {
+                                                                this.tree.expandTreeitem(this);
+                                                        }
+                                                }
+                                                flag = true;
+                                                break;
+
+                                        case this.keyCode.LEFT:
+                                                if (this.isExpandable && this.isExpanded()) {
+                                                        this.tree.collapseTreeitem(this);
+                                                        flag = true;
+                                                }
+                                                else {
+                                                        if (this.inGroup) {
+                                                                this.tree.setFocusToParentItem(this);
+                                                                flag = true;
+                                                        }
+                                                }
+                                                break;
+
+                                        case this.keyCode.HOME:
+                                                this.tree.setFocusToFirstItem();
+                                                flag = true;
+                                                break;
+
+                                        case this.keyCode.END:
+                                                this.tree.setFocusToLastItem();
+                                                flag = true;
+                                                break;
+
+                                        default:
+                                                if (isPrintableCharacter(_char)) {
+                                                        printableCharacter(this);
+                                                }
+                                                break;
+                                }
+                        }
+
+                        if (flag) {
+                                event.stopPropagation();
+                                event.preventDefault();
+                        }
+                };
+
+                TreeitemLink.prototype.handleClick = function (event) {
+
+                        // only process click events that directly happened on this treeitem
+                        if (event.target !== this.domNode && event.target !== this.domNode.firstElementChild) {
+                                return;
+                        }
+
+                        if (this.isExpandable) {
+                                if (this.isExpanded()) {
+                                        this.tree.collapseTreeitem(this);
+                                }
+                                else {
+                                        this.tree.expandTreeitem(this);
+                                }
+                                event.stopPropagation();
+                        }
+                };
+
+                TreeitemLink.prototype.handleFocus = function (event) {
+                        var node = this.domNode;
+                        if (this.isExpandable) {
+                                node = node.firstElementChild;
+                        }
+                        node.classList.add('focus');
+                };
+
+                TreeitemLink.prototype.handleBlur = function (event) {
+                        var node = this.domNode;
+                        if (this.isExpandable) {
+                                node = node.firstElementChild;
+                        }
+                        node.classList.remove('focus');
+                };
+
+                TreeitemLink.prototype.handleMouseOver = function (event) {
+                        event.currentTarget.classList.add('hover');
+                };
+
+                TreeitemLink.prototype.handleMouseOut = function (event) {
+                        event.currentTarget.classList.remove('hover');
+                };
+
+                return TreeitemLink;
+        })();
+
+        /**
+         * Creates a new TreeLinks.
+         *
+         * @since 4.9.0
+         * @class
+         * @private
+         * @see {@link https://www.w3.org/TR/wai-aria-practices-1.1/examples/treeview/treeview-2/treeview-2b.html|W3C Treeview Example}
+         * @license W3C-20150513
+         */
+        TreeLinks = (function () {
+                /*
+                 *   This content is licensed according to the W3C Software License at
+                 *   https://www.w3.org/Consortium/Legal/2015/copyright-software-and-document
+                 *
+                 *   File:   TreeLinks.js
+                 *
+                 *   Desc:   Tree widget that implements ARIA Authoring Practices
+                 *           for a tree being used as a file viewer
+                 *
+                 *   Author: Jon Gunderson, Ku Ja Eun and Nicholas Hoyt
+                 */
+
+                /*
+                 *   @constructor
+                 *
+                 *   @desc
+                 *       Tree item object for representing the state and user interactions for a
+                 *       tree widget
+                 *
+                 *   @param node
+                 *       An element with the role=tree attribute
+                 */
+
+                var TreeLinks = function (node) {
+                        // Check whether node is a DOM element
+                        if (typeof node !== 'object') {
+                                return;
+                        }
+
+                        this.domNode = node;
+
+                        this.treeitems = [];
+                        this.firstChars = [];
+
+                        this.firstTreeitem = null;
+                        this.lastTreeitem = null;
+
+                };
+
+                TreeLinks.prototype.init = function () {
+
+                        function findTreeitems(node, tree, group) {
+
+                                var elem = node.firstElementChild;
+                                var ti = group;
+
+                                while (elem) {
+
+                                        if ((elem.tagName.toLowerCase() === 'li' && elem.firstElementChild.tagName.toLowerCase() === 'span') || elem.tagName.toLowerCase() === 'a') {
+                                                ti = new TreeitemLink(elem, tree, group);
+                                                ti.init();
+                                                tree.treeitems.push(ti);
+                                                tree.firstChars.push(ti.label.substring(0, 1).toLowerCase());
+                                        }
+
+                                        if (elem.firstElementChild) {
+                                                findTreeitems(elem, tree, ti);
+                                        }
+
+                                        elem = elem.nextElementSibling;
+                                }
+                        }
+
+                        // initialize pop up menus
+                        if (!this.domNode.getAttribute('role')) {
+                                this.domNode.setAttribute('role', 'tree');
+                        }
+
+                        findTreeitems(this.domNode, this, false);
+
+                        this.updateVisibleTreeitems();
+
+                        this.firstTreeitem.domNode.tabIndex = 0;
+
+                };
+
+                TreeLinks.prototype.setFocusToItem = function (treeitem) {
+
+                        for (var i = 0; i < this.treeitems.length; i++) {
+                                var ti = this.treeitems[i];
+
+                                if (ti === treeitem) {
+                                        ti.domNode.tabIndex = 0;
+                                        ti.domNode.focus();
+                                }
+                                else {
+                                        ti.domNode.tabIndex = -1;
+                                }
+                        }
+
+                };
+
+                TreeLinks.prototype.setFocusToNextItem = function (currentItem) {
+
+                        var nextItem = false;
+
+                        for (var i = (this.treeitems.length - 1); i >= 0; i--) {
+                                var ti = this.treeitems[i];
+                                if (ti === currentItem) {
+                                        break;
+                                }
+                                if (ti.isVisible) {
+                                        nextItem = ti;
+                                }
+                        }
+
+                        if (nextItem) {
+                                this.setFocusToItem(nextItem);
+                        }
+
+                };
+
+                TreeLinks.prototype.setFocusToPreviousItem = function (currentItem) {
+
+                        var prevItem = false;
+
+                        for (var i = 0; i < this.treeitems.length; i++) {
+                                var ti = this.treeitems[i];
+                                if (ti === currentItem) {
+                                        break;
+                                }
+                                if (ti.isVisible) {
+                                        prevItem = ti;
+                                }
+                        }
+
+                        if (prevItem) {
+                                this.setFocusToItem(prevItem);
+                        }
+                };
+
+                TreeLinks.prototype.setFocusToParentItem = function (currentItem) {
+
+                        if (currentItem.groupTreeitem) {
+                                this.setFocusToItem(currentItem.groupTreeitem);
+                        }
+                };
+
+                TreeLinks.prototype.setFocusToFirstItem = function () {
+                        this.setFocusToItem(this.firstTreeitem);
+                };
+
+                TreeLinks.prototype.setFocusToLastItem = function () {
+                        this.setFocusToItem(this.lastTreeitem);
+                };
+
+                TreeLinks.prototype.expandTreeitem = function (currentItem) {
+
+                        if (currentItem.isExpandable) {
+                                currentItem.domNode.setAttribute('aria-expanded', true);
+                                this.updateVisibleTreeitems();
+                        }
+
+                };
+
+                TreeLinks.prototype.expandAllSiblingItems = function (currentItem) {
+                        for (var i = 0; i < this.treeitems.length; i++) {
+                                var ti = this.treeitems[i];
+
+                                if ((ti.groupTreeitem === currentItem.groupTreeitem) && ti.isExpandable) {
+                                        this.expandTreeitem(ti);
+                                }
+                        }
+
+                };
+
+                TreeLinks.prototype.collapseTreeitem = function (currentItem) {
+
+                        var groupTreeitem = false;
+
+                        if (currentItem.isExpanded()) {
+                                groupTreeitem = currentItem;
+                        }
+                        else {
+                                groupTreeitem = currentItem.groupTreeitem;
+                        }
+
+                        if (groupTreeitem) {
+                                groupTreeitem.domNode.setAttribute('aria-expanded', false);
+                                this.updateVisibleTreeitems();
+                                this.setFocusToItem(groupTreeitem);
+                        }
+
+                };
+
+                TreeLinks.prototype.updateVisibleTreeitems = function () {
+
+                        this.firstTreeitem = this.treeitems[0];
+
+                        for (var i = 0; i < this.treeitems.length; i++) {
+                                var ti = this.treeitems[i];
+
+                                var parent = ti.domNode.parentNode;
+
+                                ti.isVisible = true;
+
+                                while (parent && (parent !== this.domNode)) {
+
+                                        if (parent.getAttribute('aria-expanded') == 'false') {
+                                                ti.isVisible = false;
+                                        }
+                                        parent = parent.parentNode;
+                                }
+
+                                if (ti.isVisible) {
+                                        this.lastTreeitem = ti;
+                                }
+                        }
+
+                };
+
+                TreeLinks.prototype.setFocusByFirstCharacter = function (currentItem, _char) {
+                        var start, index;
+                        _char = _char.toLowerCase();
+
+                        // Get start index for search based on position of currentItem
+                        start = this.treeitems.indexOf(currentItem) + 1;
+                        if (start === this.treeitems.length) {
+                                start = 0;
+                        }
+
+                        // Check remaining slots in the menu
+                        index = this.getIndexFirstChars(start, _char);
+
+                        // If not found in remaining slots, check from beginning
+                        if (index === -1) {
+                                index = this.getIndexFirstChars(0, _char);
+                        }
+
+                        // If match was found...
+                        if (index > -1) {
+                                this.setFocusToItem(this.treeitems[index]);
+                        }
+                };
+
+                TreeLinks.prototype.getIndexFirstChars = function (startIndex, _char) {
+                        for (var i = startIndex; i < this.firstChars.length; i++) {
+                                if (this.treeitems[i].isVisible) {
+                                        if (_char === this.firstChars[i]) {
+                                                return i;
+                                        }
+                                }
+                        }
+                        return -1;
+                };
+
+                return TreeLinks;
+        })();
+
+        /* jshint ignore:end */
+        /* jscs:enable */
+        /* eslint-enable */
+
         return component;
 })( jQuery );

src/wp-admin/plugin-editor.php

@@ -231 +231 @@
 </div>
 
 <div id="templateside">
-        <h2><?php _e( 'Plugin Files' ); ?></h2>
+        <h2 id="plugin-files-label"><?php _e( 'Plugin Files' ); ?></h2>
 
         <?php
         $plugin_editable_files = array();
@@ -241 +241 @@
                 }
         }
         ?>
-        <ul>
-        <?php foreach ( $plugin_editable_files as $plugin_file ) : ?>
-                <li class="<?php echo esc_attr( $file === $plugin_file ? 'notice notice-info' : '' ); ?>">
-                        <a href="plugin-editor.php?file=<?php echo urlencode( $plugin_file ); ?>&amp;plugin=<?php echo urlencode( $plugin ); ?>"><?php echo esc_html( preg_replace( '#^.+?/#', '', $plugin_file ) ); ?></a>
-                </li>
-        <?php endforeach; ?>
+        <ul role="tree" aria-labelledby="plugin-files-label">
+        <li role="treeitem" tabindex="-1" aria-expanded="true"
+                aria-level="1"
+                aria-posinset="1"
+                aria-setsize="1">
+                <ul role="group" style="padding-left: 0;">
+                        <?php wp_print_plugin_file_tree( wp_make_plugin_file_tree( $plugin_editable_files ) ); ?>
+                </ul>
         </ul>
 </div>
 <form name="template" id="template" action="plugin-editor.php" method="post">

src/wp-admin/theme-editor.php

@@ -89 +89 @@
         }
 }
 
+// Move functions.php and style.css to the top.
+if ( isset( $allowed_files['functions.php'] ) ) {
+        $allowed_files = array( 'functions.php' => $allowed_files['functions.php'] ) + $allowed_files;
+}
+if ( isset( $allowed_files['style.css'] ) ) {
+        $allowed_files = array( 'style.css' => $allowed_files['style.css'] ) + $allowed_files;
+}
+
 if ( empty( $file ) ) {
         $relative_file = 'style.css';
         $file = $allowed_files['style.css'];
@@ -205 +213 @@
 if ( $theme->errors() )
         echo '<div class="error"><p><strong>' . __( 'This theme is broken.' ) . '</strong> ' . $theme->errors()->get_error_message() . '</p></div>';
 ?>
-        <div id="templateside">
-<?php
-if ( $allowed_files ) :
-        $previous_file_type = '';
-
-        foreach ( $allowed_files as $filename => $absolute_filename ) :
-                $file_type = substr( $filename, strrpos( $filename, '.' ) );
-
-                if ( $file_type !== $previous_file_type ) {
-                        if ( '' !== $previous_file_type ) {
-                                echo "\t</ul>\n";
-                        }
-
-                        switch ( $file_type ) {
-                                case '.php':
-                                        if ( $has_templates || $theme->parent() ) :
-                                                echo "\t<h2>" . __( 'Templates' ) . "</h2>\n";
-                                                if ( $theme->parent() ) {
-                                                        echo '<p class="howto">' . sprintf( __( 'This child theme inherits templates from a parent theme, %s.' ),
-                                                                sprintf( '<a href="%s">%s</a>',
-                                                                        self_admin_url( 'theme-editor.php?theme=' . urlencode( $theme->get_template() ) ),
-                                                                        $theme->parent()->display( 'Name' )
-                                                                )
-                                                        ) . "</p>\n";
-                                                }
-                                        endif;
-                                        break;
-                                case '.css':
-                                        echo "\t<h2>" . _x( 'Styles', 'Theme stylesheets in theme editor' ) . "</h2>\n";
-                                        break;
-                                default:
-                                        /* translators: %s: file extension */
-                                        echo "\t<h2>" . sprintf( __( '%s files' ), $file_type ) . "</h2>\n";
-                                        break;
-                        }
-
-                        echo "\t<ul>\n";
+<div id="templateside">
+        <h2 id="theme-files-label"><?php _e( 'Theme Files' ); ?></h2>
+        <?php
+        if ( $has_templates || $theme->parent() ) :
+                if ( $theme->parent() ) {
+                        /* translators: %s: link to edit parent theme */
+                        echo '<p class="howto">' . sprintf( __( 'This child theme inherits templates from a parent theme, %s.' ),
+                                sprintf( '<a href="%s">%s</a>',
+                                        self_admin_url( 'theme-editor.php?theme=' . urlencode( $theme->get_template() ) ),
+                                        $theme->parent()->display( 'Name' )
+                                )
+                        ) . "</p>\n";
                 }
-
-                $file_description = esc_html( get_file_description( $filename ) );
-                if ( $filename !== basename( $absolute_filename ) || $file_description !== $filename ) {
-                        $file_description .= '<br /><span class="nonessential">(' . esc_html( $filename ) . ')</span>';
-                }
-
-                if ( $absolute_filename === $file ) {
-                        $file_description = '<span class="notice notice-info">' . $file_description . '</span>';
-                }
-
-                $previous_file_type = $file_type;
-?>
-                <li><a href="theme-editor.php?file=<?php echo urlencode( $filename ) ?>&amp;theme=<?php echo urlencode( $stylesheet ) ?>"><?php echo $file_description; ?></a></li>
-<?php
-        endforeach;
-?>
-</ul>
-<?php endif; ?>
+        endif;
+        ?>
+        <ul role="tree" aria-labelledby="theme-files-label">
+                <li role="treeitem" tabindex="-1" aria-expanded="true"
+                        aria-level="1"
+                        aria-posinset="1"
+                        aria-setsize="1">
+                        <ul role="group" style="padding-left: 0;">
+                                <?php wp_print_theme_file_tree( wp_make_theme_file_tree( $allowed_files ) ); ?>
+                        </ul>
+                </li>
+        </ul>
 </div>
+
 <?php if ( $error ) :
         echo '<div class="error"><p>' . __('Oops, no such file exists! Double check the name and try again, merci.') . '</p></div>';
 else : ?>