MDL-79144 hooks: allow hooks to return tags

lib/classes/hook/described_hook.php

@@ -35,4 +35,11 @@ interface described_hook {
      * @return string
      */
     public static function get_hook_description(): string;
+
+    /**
+     * List of tags that describe this hook.
+     *
+     * @return string[]
+     */
+    public static function get_hook_tags(): array;
 }

lib/classes/hooks.php

@@ -80,6 +80,7 @@ final class hooks implements \core\hook\discovery_agent {
 
             if (is_subclass_of($classname, \core\hook\described_hook::class)) {
                 $hooks[$classname]['description'] = $classname::get_hook_description();
+                $hooks[$classname]['tags'] = $classname::get_hook_tags();
             }
         }
 

lib/tests/fixtures/hook/hook.php

@@ -41,4 +41,13 @@ final class hook implements
     public static function get_deprecated_plugin_callbacks(): array {
         return ['oldcallback'];
     }
+
+    /**
+     * List of tags that describe this hook.
+     *
+     * @return string[]
+     */
+    public static function get_hook_tags(): array {
+        return ['test'];
+    }
 }

lib/tests/fixtures/hook/stoppablehook.php

@@ -53,4 +53,13 @@ final class stoppablehook implements
     public function isPropagationStopped(): bool {
         return $this->stopped;
     }
+
+    /**
+     * List of tags that describe this hook.
+     *
+     * @return string[]
+     */
+    public static function get_hook_tags(): array {
+        return ['test'];
+    }
 }