Merge branch 'MDL-81063-main' of https://github.com/andrewnicols/moodle

admin/tool/usertours/amd/src/usertours.js

@@ -43,8 +43,8 @@ const findMatchingTour = (tourDetails, filters) => {
  */
 export const init = async(tourDetails, filters) => {
     const requirements = [];
-    filters.forEach(filter => {
-        requirements.push(import(`tool_usertours/filter_${filter}`));
+    filters.forEach((filter) => {
+        requirements.push(import(filter));
     });
 
     const filterPlugins = await Promise.all(requirements);

admin/tool/usertours/classes/helper.php

@@ -16,6 +16,7 @@
 
 namespace tool_usertours;
 
+use coding_exception;
 use core\output\inplace_editable;
 
 /**
@@ -534,10 +535,7 @@ class helper {
                 ];
             }, $tours);
 
-            $filternames = [];
-            foreach ($filters as $filter) {
-                    $filternames[] = $filter::get_filter_name();
-            }
+            $filternames = self::get_clientside_filter_module_names($filters);
 
             $PAGE->requires->js_call_amd('tool_usertours/usertours', 'init', [
                 $tourdetails,
@@ -546,19 +544,48 @@ class helper {
         }
     }
 
+    /**
+     * Get the JS module names for the filters.
+     *
+     * @param array $filters
+     * @return array
+     * @throws coding_exception
+     */
+    public static function get_clientside_filter_module_names(array $filters): array {
+        $filternames = [];
+        foreach ($filters as $filter) {
+            if ($component = \core_component::get_component_from_classname($filter)) {
+                $filternames[] = sprintf(
+                    "%s/filter_%s",
+                    $component,
+                    $filter::get_filter_name(),
+                );
+            } else {
+                throw new \coding_exception("Could not determine component for filter class {$filter}");
+            }
+        }
+
+        return $filternames;
+    }
+
     /**
      * Get a list of all possible filters.
      *
      * @return  array
      */
     public static function get_all_filters() {
-        $filters = \core_component::get_component_classes_in_namespace('tool_usertours', 'local\filter');
-        $filters = array_keys($filters);
+        $hook = new hook\before_serverside_filter_fetch(array_keys(
+            \core_component::get_component_classes_in_namespace('tool_usertours', 'local\filter')
+        ));
+        \core\di::get(\core\hook\manager::class)->dispatch($hook);
 
-        $filters = array_filter($filters, function ($filterclass) {
-            $rc = new \ReflectionClass($filterclass);
-            return $rc->isInstantiable();
-        });
+        $filters = array_filter(
+            $hook->get_filter_list(),
+            function ($filterclass) {
+                $rc = new \ReflectionClass($filterclass);
+                return $rc->isInstantiable();
+            }
+        );
 
         $filters = array_merge($filters, static::get_all_clientside_filters());
 
@@ -571,13 +598,18 @@ class helper {
      * @return  array
      */
     public static function get_all_clientside_filters() {
-        $filters = \core_component::get_component_classes_in_namespace('tool_usertours', 'local\clientside_filter');
-        $filters = array_keys($filters);
+        $hook = new hook\before_clientside_filter_fetch(array_keys(
+            \core_component::get_component_classes_in_namespace('tool_usertours', 'local\clientside_filter')
+        ));
+        \core\di::get(\core\hook\manager::class)->dispatch($hook);
 
-        $filters = array_filter($filters, function ($filterclass) {
-            $rc = new \ReflectionClass($filterclass);
-            return $rc->isInstantiable();
-        });
+        $filters = array_filter(
+            $hook->get_filter_list(),
+            function ($filterclass) {
+                $rc = new \ReflectionClass($filterclass);
+                return $rc->isInstantiable();
+            }
+        );
 
         return $filters;
     }

admin/tool/usertours/classes/hook/before_clientside_filter_fetch.php

@@ -0,0 +1,74 @@
+<?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 tool_usertours\hook;
+
+/**
+ * Provides the ability to add and remove custom client-side filters to the user tour filter list.
+ *
+ * @package    tool_usertours
+ * @copyright  2024 Andrew Lyons <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+#[\core\attribute\label('Provides the ability to add and remove custom client-side filters to the user tour filter list.')]
+#[\core\attribute\tags('tool_usertours')]
+class before_clientside_filter_fetch {
+    /**
+     * Create a new instance of the hook.
+     *
+     * @param array $filters
+     */
+    public function __construct(
+        /** @var array The list of filters applied */
+        protected array $filters,
+    ) {
+    }
+
+    /**
+     * Add a filter classname to the list of filters to be processed.
+     *
+     * @param string $classname
+     * @return self
+     */
+    public function add_filter_by_classname(string $classname): self {
+        if (!\is_a($classname, \tool_usertours\local\clientside_filter\clientside_filter::class, true)) {
+            throw new \coding_exception("Invalid clientside filter class {$classname}");
+        }
+        $this->filters[] = $classname;
+
+        return $this;
+    }
+
+    /**
+     * Remove a filter classname from the list of filters to be processed.
+     *
+     * @param string $classname
+     * @return self
+     */
+    public function remove_filter_by_classname(string $classname): self {
+        $this->filters = array_filter($this->filters, fn($filter) => $filter !== $classname);
+        return $this;
+    }
+
+    /**
+     * Get the list of filters to be processed.
+     *
+     * @return array
+     */
+    public function get_filter_list(): array {
+        return $this->filters;
+    }
+}

admin/tool/usertours/classes/hook/before_serverside_filter_fetch.php

@@ -0,0 +1,78 @@
+<?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 tool_usertours\hook;
+
+/**
+ * Provides the ability to add and remove custom server-side filters to the user tour filter list.
+ *
+ * @package    tool_usertours
+ * @copyright  2024 Andrew Lyons <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+#[\core\attribute\label('Provides the ability to add and remove custom server-side filters to the user tour filter list.')]
+#[\core\attribute\tags('tool_usertours')]
+class before_serverside_filter_fetch {
+    /**
+     * Create a new instance of the hook.
+     *
+     * @param array $filters
+     */
+    public function __construct(
+        /** @var array The list of filters applied */
+        protected array $filters,
+    ) {
+    }
+
+    /**
+     * Add a filter classname to the list of filters to be processed.
+     *
+     * @param string $classname
+     * @return self
+     */
+    public function add_filter_by_classname(string $classname): self {
+        if (!\is_a($classname, \tool_usertours\local\filter\base::class, true)) {
+            throw new \coding_exception("Invalid filter class {$classname}");
+        }
+
+        if (\is_a($classname, \tool_usertours\local\clientside_filter\clientside_filter::class, true)) {
+            throw new \coding_exception("Invalid filter class {$classname} (client-side filter for server-side hook)");
+        }
+
+        $this->filters[] = $classname;
+        return $this;
+    }
+
+    /**
+     * Remove a filter classname from the list of filters to be processed.
+     *
+     * @param string $classname
+     * @return self
+     */
+    public function remove_filter_by_classname(string $classname): self {
+        $this->filters = array_filter($this->filters, fn($filter) => $filter !== $classname);
+        return $this;
+    }
+
+    /**
+     * Get the list of filters to be processed.
+     *
+     * @return array
+     */
+    public function get_filter_list(): array {
+        return $this->filters;
+    }
+}

admin/tool/usertours/tests/fixtures/clientside_filter_for_serverside_hook.php

@@ -0,0 +1,45 @@
+<?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/>.
+
+/**
+ * Hook fixtures for testing of hooks.
+ *
+ * @package    tool_usertours
+ * @copyright  2024 Andrew Lyons <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace tool_usertours\test\hook\clientside_filter_for_serverside_hook;
+
+defined('MOODLE_INTERNAL') || die();
+
+final class filter_class extends \tool_usertours\local\clientside_filter\clientside_filter {
+}
+
+final class callback {
+    public static function callme(
+        \tool_usertours\hook\before_serverside_filter_fetch $hook
+    ): void {
+        $hook->add_filter_by_classname(filter_class::class);
+    }
+}
+
+$callbacks = [
+    [
+        'hook' => \tool_usertours\hook\before_serverside_filter_fetch::class,
+        'callback' => callback::class . '::callme',
+    ],
+];

admin/tool/usertours/tests/fixtures/hook_fixtures.php

@@ -0,0 +1,61 @@
+<?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/>.
+
+/**
+ * Hook fixtures for testing of hooks.
+ *
+ * @package    tool_usertours
+ * @copyright  2024 Andrew Lyons <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace tool_usertours\test\hook;
+
+defined('MOODLE_INTERNAL') || die();
+
+final class serverside_filter_fixture extends \tool_usertours\local\filter\base {
+}
+
+final class clientside_filter_fixture extends \tool_usertours\local\clientside_filter\clientside_filter {
+}
+
+final class hook_fixtures {
+    public static function example_serverside_hook(
+        \tool_usertours\hook\before_serverside_filter_fetch $hook
+    ): void {
+        // Add a valid serverside and an invalid clientside filter.
+        $hook->add_filter_by_classname(\tool_usertours\test\hook\serverside_filter_fixture::class);
+        $hook->remove_filter_by_classname(\tool_usertours\local\filter\accessdate::class);
+    }
+
+    public static function example_clientside_hook(
+        \tool_usertours\hook\before_clientside_filter_fetch $hook
+    ): void {
+        $hook->add_filter_by_classname(\tool_usertours\test\hook\clientside_filter_fixture::class);
+        $hook->remove_filter_by_classname(\tool_usertours\local\clientside_filter\cssselector::class);
+    }
+}
+
+$callbacks = [
+    [
+        'hook' => \tool_usertours\hook\before_serverside_filter_fetch::class,
+        'callback' => \tool_usertours\test\hook\hook_fixtures::class . '::example_serverside_hook',
+    ],
+    [
+        'hook' => \tool_usertours\hook\before_clientside_filter_fetch::class,
+        'callback' => \tool_usertours\test\hook\hook_fixtures::class . '::example_clientside_hook',
+    ],
+];

admin/tool/usertours/tests/fixtures/invalid_clientside_hook_fixture.php

@@ -0,0 +1,43 @@
+<?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/>.
+
+/**
+ * Hook fixtures for testing of hooks.
+ *
+ * @package    tool_usertours
+ * @copyright  2024 Andrew Lyons <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+final class nocomponent_clientside_filter_fixture extends \tool_usertours\local\clientside_filter\clientside_filter {
+}
+
+final class nocomponent_clientside_hook_fixtures {
+    public static function example_clientside_hook(
+        \tool_usertours\hook\before_clientside_filter_fetch $hook
+    ): void {
+        $hook->add_filter_by_classname(\nocomponent_clientside_filter_fixture::class);
+    }
+}
+
+$callbacks = [
+    [
+        'hook' => \tool_usertours\hook\before_clientside_filter_fetch::class,
+        'callback' => \nocomponent_clientside_hook_fixtures::class . '::example_clientside_hook',
+    ],
+];

admin/tool/usertours/tests/fixtures/invalid_serverside_hook_fixture.php

@@ -0,0 +1,43 @@
+<?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/>.
+
+/**
+ * Hook fixtures for testing of hooks.
+ *
+ * @package    tool_usertours
+ * @copyright  2024 Andrew Lyons <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+final class nocomponent_serverside_filter_fixture {
+}
+
+final class nocomponent_serverside_hook_fixtures {
+    public static function example_serverside_hook(
+        \tool_usertours\hook\before_serverside_filter_fetch $hook
+    ): void {
+        $hook->add_filter_by_classname(\nocomponent_serverside_filter_fixture::class);
+    }
+}
+
+$callbacks = [
+    [
+        'hook' => \tool_usertours\hook\before_serverside_filter_fetch::class,
+        'callback' => \nocomponent_serverside_hook_fixtures::class . '::example_serverside_hook',
+    ],
+];

admin/tool/usertours/tests/fixtures/serverside_filter_for_clientside_hook.php

@@ -0,0 +1,45 @@
+<?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/>.
+
+/**
+ * Hook fixtures for testing of hooks.
+ *
+ * @package    tool_usertours
+ * @copyright  2024 Andrew Lyons <andrew@nicols.co.uk>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace tool_usertours\test\hook\serverside_filter_for_clientside_hook;
+
+defined('MOODLE_INTERNAL') || die();
+
+final class filter_class extends \tool_usertours\local\filter\base {
+}
+
+final class callback {
+    public static function callme(
+        \tool_usertours\hook\before_clientside_filter_fetch $hook
+    ): void {
+        $hook->add_filter_by_classname(filter_class::class);
+    }
+}
+
+$callbacks = [
+    [
+        'hook' => \tool_usertours\hook\before_clientside_filter_fetch::class,
+        'callback' => callback::class . '::callme',
+    ],
+];

admin/tool/usertours/tests/helper_test.php

@@ -16,17 +16,18 @@
 
 namespace tool_usertours;
 
-use advanced_testcase;
-
 /**
  * Tests for helper.
  *
  * @package    tool_usertours
+ * @category   test
  * @copyright  2022 Huong Nguyen <huongnv13@gmail.com>
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- * @covers   \tool_usertours\helper
+ * @covers \tool_usertours\helper
+ * @covers \tool_usertours\hook\before_serverside_filter_fetch
+ * @covers \tool_usertours\hook\before_clientside_filter_fetch
  */
-class helper_test extends advanced_testcase {
+final class helper_test extends \advanced_testcase {
     /**
      * Data Provider for get_string_from_input.
      *
@@ -71,4 +72,117 @@ class helper_test extends advanced_testcase {
     public function test_get_string_from_input($string, $expected): void {
         $this->assertEquals($expected, helper::get_string_from_input($string));
     }
+
+    public function test_get_all_filters(): void {
+        $filters = helper::get_all_filters();
+        $this->assertIsArray($filters);
+
+        array_map(
+            function ($filter) {
+                $this->assertIsString($filter);
+                $this->assertTrue(class_exists($filter));
+                $this->assertTrue(is_a($filter, \tool_usertours\local\filter\base::class, true));
+                $rc = new \ReflectionClass($filter);
+                $this->assertTrue($rc->isInstantiable());
+            },
+            $filters,
+        );
+
+        $this->assertNotContains(\tool_usertours\test\hook\serverside_filter_fixture::class, $filters);
+        $this->assertNotContains(\tool_usertours\test\hook\clientside_filter_fixture::class, $filters);
+        $this->assertContains(\tool_usertours\local\filter\accessdate::class, $filters);
+        $this->assertContains(\tool_usertours\local\clientside_filter\cssselector::class, $filters);
+
+        $filters = helper::get_all_clientside_filters();
+        array_map(
+            function ($filter) {
+                $this->assertIsString($filter);
+            },
+            $filters,
+        );
+    }
+
+    public function test_get_invalid_server_filter(): void {
+        \core\di::set(
+            \core\hook\manager::class,
+            \core\hook\manager::phpunit_get_instance([
+                'test_plugin1' => __DIR__ . '/fixtures/invalid_serverside_hook_fixture.php',
+            ]),
+        );
+
+        $this->expectException(\coding_exception::class);
+        helper::get_all_filters();
+    }
+
+    public function test_clientside_filter_for_serverside_hook(): void {
+        \core\di::set(
+            \core\hook\manager::class,
+            \core\hook\manager::phpunit_get_instance([
+                'test_plugin1' => __DIR__ . '/fixtures/clientside_filter_for_serverside_hook.php',
+            ]),
+        );
+
+        $this->expectException(\coding_exception::class);
+        helper::get_all_filters();
+    }
+
+    public function test_serverside_filter_for_clientside_hook(): void {
+        \core\di::set(
+            \core\hook\manager::class,
+            \core\hook\manager::phpunit_get_instance([
+                'test_plugin1' => __DIR__ . '/fixtures/serverside_filter_for_clientside_hook.php',
+            ]),
+        );
+
+        $this->expectException(\coding_exception::class);
+        helper::get_all_clientside_filters();
+    }
+
+    public function test_filter_hooks(): void {
+        \core\di::set(
+            \core\hook\manager::class,
+            \core\hook\manager::phpunit_get_instance([
+                'test_plugin1' => __DIR__ . '/fixtures/hook_fixtures.php',
+            ]),
+        );
+
+        $filters = helper::get_all_filters();
+        $this->assertIsArray($filters);
+
+        // Check the modifications from the serverside hook.
+        $this->assertContains(\tool_usertours\test\hook\serverside_filter_fixture::class, $filters);
+        $this->assertNotContains(\tool_usertours\test\hook\another_clientside_filter_fixture::class, $filters);
+        $this->assertNotContains(\tool_usertours\local\filter\accessdate::class, $filters);
+
+        // Check the modifications from the clientside hook.
+        $this->assertContains(\tool_usertours\test\hook\clientside_filter_fixture::class, $filters);
+        $this->assertNotContains(\tool_usertours\test\hook\another_serverside_filter_fixture::class, $filters);
+        $this->assertNotContains(\tool_usertours\local\clientside_filter\cssselector::class, $filters);
+
+        array_map(
+            function ($filter) {
+                $this->assertIsString($filter);
+                $this->assertTrue(class_exists($filter));
+                $this->assertTrue(is_a($filter, \tool_usertours\local\filter\base::class, true));
+                $rc = new \ReflectionClass($filter);
+                $this->assertTrue($rc->isInstantiable());
+            },
+            $filters,
+        );
+    }
+
+    public function test_get_clientside_filter_module_names(): void {
+        \core\di::set(
+            \core\hook\manager::class,
+            \core\hook\manager::phpunit_get_instance([
+                'test_plugin1' => __DIR__ . '/fixtures/invalid_clientside_hook_fixture.php',
+            ]),
+        );
+
+        $filters = helper::get_all_clientside_filters();
+
+        $this->expectException(\coding_exception::class);
+        $this->expectExceptionMessageMatches('/Could not determine component/');
+        helper::get_clientside_filter_module_names($filters);
+    }
 }

admin/tool/usertours/upgrade.txt

@@ -1,5 +1,12 @@
 This files describes API changes in the tool_usertours code.
 
+=== 4.4 ===
+* New hooks have been provided to allow plugins to define their own server-side, and client-side user tour filters.
+  The new hooks are named:
+  - \tool_usertours\hook\before_serverside_filter_fetch
+  - \tool_usertours\hook\before_clientside_filter_fetch
+  These hooks allow addition, and removal, of filters.
+
 === 4.0 ===
 * The `tourconfig` property returned by the `tool_usertours_fetch_and_start_tour`
   external method has also an `endtourlabel` property that contains the label to be used

lib/classes/component.php

@@ -1090,6 +1090,35 @@ $cache = ' . var_export($cache, true) . ';
         return [$type, $plugin];
     }
 
+    /**
+     * Fetch the component name from a Moodle PSR-like namespace.
+     *
+     * Note: Classnames in the flat underscore_class_name_format are not supported.
+     *
+     * @param string $classname
+     * @return null|string The component name, or null if a matching component was not found
+     */
+    public static function get_component_from_classname(string $classname): ?string {
+        $components = static::get_component_names(true);
+
+        $classname = ltrim($classname, '\\');
+
+        // Prefer PSR-4 classnames.
+        $parts = explode('\\', $classname);
+        if ($parts) {
+            $component = array_shift($parts);
+            if (array_search($component, $components) !== false) {
+                return $component;
+            }
+        }
+
+        // Note: Frankenstyle classnames are not supported as they lead to false positives, for example:
+        // \core_typo\example => \core instead of \core_typo because it does not exist
+        // Please *do not* add support for Frankenstyle classnames. They will break other things.
+
+        return null;
+    }
+
     /**
      * Return exact absolute path to a plugin directory.
      *
@@ -1407,18 +1436,16 @@ $cache = ' . var_export($cache, true) . ';
     }
 
     /**
-     * Returns a list of frankenstyle component names.
+     * Returns a list of frankenstyle component names, including all plugins, subplugins, and subsystems.
      *
-     * E.g.
-     *  [
-     *      'core_course',
-     *      'core_message',
-     *      'mod_assign',
-     *      ...
-     *  ]
-     * @return array the list of frankenstyle component names.
+     * Note: By default the 'core' subsystem is not included.
+     *
+     * @param bool $includecore Whether to include the 'core' subsystem
+     * @return string[] the list of frankenstyle component names.
      */
-    public static function get_component_names(): array {
+    public static function get_component_names(
+        bool $includecore = false,
+    ): array {
         $componentnames = [];
         // Get all plugins.
         foreach (self::get_plugin_types() as $plugintype => $typedir) {
@@ -1430,6 +1457,11 @@ $cache = ' . var_export($cache, true) . ';
         foreach (self::get_core_subsystems() as $subsystemname => $subsystempath) {
             $componentnames[] = 'core_' . $subsystemname;
         }
+
+        if ($includecore) {
+            $componentnames[] = 'core';
+        }
+
         return $componentnames;
     }
 

lib/tests/component_test.php

@@ -411,6 +411,73 @@ class component_test extends advanced_testcase {
         }
     }
 
+    /**
+     * Unit tests for get_component_from_classname.
+     *
+     * @dataProvider get_component_from_classname_provider
+     * @param string $classname The class name to test
+     * @param string|null $expected The expected component
+     * @covers \core_component::get_component_from_classname
+     */
+    public function test_get_component_from_classname(
+        string $classname,
+        string|null $expected,
+    ): void {
+        $this->assertEquals(
+            $expected,
+            \core_component::get_component_from_classname($classname),
+        );
+    }
+
+    /**
+     * Data provider for get_component_from_classname tests.
+     *
+     * @return array
+     */
+    public static function get_component_from_classname_provider(): array {
+        // Start off with testcases which have the leading \.
+        $testcases = [
+            // Core.
+            [\core\example::class, 'core'],
+
+            // A core subsystem.
+            [\core_message\example::class, 'core_message'],
+
+            // A fake core subsystem.
+            [\core_fake\example::class, null],
+
+            // A plugin.
+            [\mod_forum\example::class, 'mod_forum'],
+
+            // A plugin in the old style is not supported.
+            [\mod_forum_example::class, null],
+
+            // A fake plugin.
+            [\mod_fake\example::class, null],
+
+            // A subplugin.
+            [\tiny_link\example::class, 'tiny_link'],
+        ];
+
+        // Duplicate the testcases, adding a nested namespace.
+        $testcases = array_merge(
+            $testcases,
+            array_map(
+                fn ($testcase) => [$testcase[0] . '\\in\\sub\\directory', $testcase[1]],
+                $testcases,
+            ),
+        );
+
+        // Duplicate the testcases, removing the leading \.
+        return array_merge(
+            $testcases,
+            array_map(
+                fn ($testcase) => [ltrim($testcase[0], '\\'), $testcase[1]],
+                $testcases,
+            ),
+        );
+    }
+
     public function test_deprecated_get_component_directory(): void {
         $plugintypes = core_component::get_plugin_types();
         foreach ($plugintypes as $plugintype => $fulldir) {
@@ -873,22 +940,31 @@ class component_test extends advanced_testcase {
 
     /**
      * Test the get_component_names() method.
+     *
+     * @dataProvider get_component_names_provider
+     * @param bool $includecore Whether to include core in the list.
+     * @param bool $coreexpected Whether core is expected to be in the list.
      */
-    public function test_get_component_names(): void {
+    public function test_get_component_names(
+        bool $includecore,
+        bool $coreexpected,
+    ): void {
         global $CFG;
-        $componentnames = \core_component::get_component_names();
+        $componentnames = \core_component::get_component_names($includecore);
 
         // We should have an entry for each plugin type.
         $plugintypes = \core_component::get_plugin_types();
         $numplugintypes = 0;
-        foreach ($plugintypes as $type => $typedir) {
-            foreach (\core_component::get_plugin_list($type) as $plugin) {
-                $numplugintypes++;
-            }
+        foreach (array_keys($plugintypes) as $type) {
+            $numplugintypes += count(\core_component::get_plugin_list($type));
         }
         // And an entry for each core subsystem.
         $numcomponents = $numplugintypes + count(\core_component::get_core_subsystems());
 
+        if ($coreexpected) {
+            // Add one for core.
+            $numcomponents++;
+        }
         $this->assertEquals($numcomponents, count($componentnames));
 
         // Check a few of the known plugin types to confirm their presence at their respective type index.
@@ -896,6 +972,23 @@ class component_test extends advanced_testcase {
         $this->assertContains('mod_forum', $componentnames);
         $this->assertContains('tool_usertours', $componentnames);
         $this->assertContains('core_favourites', $componentnames);
+        if ($coreexpected) {
+            $this->assertContains('core', $componentnames);
+        } else {
+            $this->assertNotContains('core', $componentnames);
+        }
+    }
+
+    /**
+     * Data provider for get_component_names() test.
+     *
+     * @return array
+     */
+    public static function get_component_names_provider(): array {
+        return [
+            [false, false],
+            [true, true],
+        ];
     }
 
     /**