MDL-80746 core_course: fix user_selector rendering

This change:
- Moved the user selector button content out into its own
named_templatable renderable + updates calling code

course/classes/output/actionbar/user_selector.php

@@ -40,57 +40,38 @@ class user_selector extends comboboxsearch {
      * @param int|null $instanceid The instance ID.
      */
     public function __construct(
-        stdClass $course,
-        moodle_url $resetlink,
-        ?int $userid = null,
-        ?int $groupid = null,
-        string $usersearch = '',
-        ?int $instanceid = null
+        private stdClass $course,
+        private moodle_url $resetlink,
+        private ?int $userid = null,
+        private ?int $groupid = null,
+        private string $usersearch = '',
+        private ?int $instanceid = null
     ) {
-
-        $userselectorontent = $this->user_selector_output($course, $resetlink, $userid, $groupid, $usersearch, $instanceid);
-        parent::__construct(true, $userselectorontent, null, 'user-search d-flex',
+        // The second argument (buttoncontent) needs to be rendered here, since the comboboxsearch
+        // template expects HTML in its respective context properties. Ideally, children of comboboxsearch would leverage Mustache's
+        // blocks pragma, meaning a child template could extend the comboboxsearch, allowing rendering of the child component,
+        // instead of needing to inject the child's content HTML as part of rendering the comboboxsearch parent, as is the case
+        // here. Achieving this, however, requires a refactor of comboboxsearch. For now, this must be pre-rendered and injected.
+        parent::__construct(true, $this->user_selector_output(), null, 'user-search d-flex',
             null, 'usersearchdropdown overflow-auto', null, false);
     }
 
     /**
      * Method that generates the output for the user selector.
      *
-     * @param stdClass $course The course object.
-     * @param moodle_url|null $resetlink The reset link.
-     * @param int|null $userid The user ID.
-     * @param int|null $groupid The group ID.
-     * @param string $usersearch The user search query.
-     * @param int|null $instanceid The instance ID.
      * @return string The HTML output.
      */
-    private function user_selector_output(
-        stdClass $course,
-        ?moodle_url $resetlink = null,
-        ?int $userid = null,
-        ?int $groupid = null,
-        string $usersearch = '',
-        ?int $instanceid = null
-    ): string {
-        global $OUTPUT;
-
-        // If the user ID is set, it indicates that a user has been selected. In this case, override the user search
-        // string with the full name of the selected user.
-        if ($userid) {
-            $usersearch = fullname(\core_user::get_user($userid));
-        }
+    private function user_selector_output(): string {
+        global $PAGE;
 
-        return $OUTPUT->render_from_template('core_user/comboboxsearch/user_selector', [
-            'currentvalue' => $usersearch,
-            'courseid' => $course->id,
-            'instance' => $instanceid ?? rand(),
-            'resetlink' => $resetlink->out(false),
-            'group' => $groupid ?? 0,
-            'name' => 'usersearch',
-            'value' => json_encode([
-                'userid' => $userid,
-                'search' => $usersearch,
-            ]),
-        ]);
+        $userselectordropdown = new user_selector_button(
+            $this->course,
+            $this->resetlink,
+            $this->userid,
+            $this->groupid,
+            $this->usersearch,
+            $this->instanceid
+        );
+        return $PAGE->get_renderer('core', 'course')->render($userselectordropdown);
     }
 }

course/classes/output/actionbar/user_selector_button.php

@@ -0,0 +1,73 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+namespace core_course\output\actionbar;
+
+use core\output\named_templatable;
+use core\output\renderable;
+use core\output\renderer_base;
+use core\url;
+use stdClass;
+
+/**
+ * Renderable class for the user_selector_button.
+ *
+ * This is the button content for the user_selector renderable, which itself is an extension of the comboboxsearch component.
+ * {@see initials_selector}.
+ *
+ * @package    core_course
+ * @copyright  2024 Jake Dallimore <[email protected]>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class user_selector_button implements renderable, named_templatable {
+
+    /**
+     * The class constructor.
+     */
+    public function __construct(
+        private stdClass $course,
+        private url $resetlink,
+        private ?int $userid = null,
+        private ?int $groupid = null,
+        private string $usersearch = '',
+        private ?int $instanceid = null
+    ) {
+        // If the user ID is set, it indicates that a user has been selected. In this case, override the user search
+        // string with the full name of the selected user.
+        if ($this->userid) {
+            $this->usersearch = fullname(\core_user::get_user($this->userid));
+        }
+    }
+
+    public function export_for_template(renderer_base $output) {
+        return [
+            'currentvalue' => $this->usersearch,
+            'courseid' => $this->course->id,
+            'instance' => $this->instanceid ?? rand(),
+            'resetlink' => $this->resetlink->out(false),
+            'group' => $this->groupid ?? 0,
+            'name' => 'usersearch',
+            'value' => json_encode([
+                'userid' => $this->userid,
+                'search' => $this->usersearch,
+            ]),
+        ];
+    }
+
+    public function get_template_name(renderer_base $renderer): string {
+        return 'core_user/comboboxsearch/user_selector';
+    }
+}