MDL-72720 qtype: Implement enable_plugin() method

admin/qtypes.php

@@ -80,7 +80,8 @@ if (($disable = optional_param('disable', '', PARAM_PLUGIN)) && confirm_sesskey(
         print_error('unknownquestiontype', 'question', $thispageurl, $disable);
     }
 
-    set_config($disable . '_disabled', 1, 'question');
+    $class = \core_plugin_manager::resolve_plugininfo_class('qtype');
+    $class::enable_plugin($disable, false);
     redirect($thispageurl);
 }
 
@@ -94,7 +95,8 @@ if (($enable = optional_param('enable', '', PARAM_PLUGIN)) && confirm_sesskey())
         print_error('cannotenable', 'question', $thispageurl, $enable);
     }
 
-    unset_config($enable . '_disabled', 'question');
+    $class = \core_plugin_manager::resolve_plugininfo_class('qtype');
+    $class::enable_plugin($enable, true);
     redirect($thispageurl);
 }
 
@@ -251,4 +253,3 @@ function question_type_icon_html($action, $qtypename, $icon, $alt, $tip) {
             new pix_icon($icon, $alt, 'moodle', array('title' => '', 'class' => 'iconsmall')),
             null, array('title' => $tip));
 }
-

lib/classes/plugininfo/qtype.php

@@ -65,6 +65,29 @@ class qtype extends base {
         return $enabled;
     }
 
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        $haschanged = false;
+
+        $settingname = $pluginname . '_disabled';
+        $oldvalue = get_config('question', $settingname);
+        $disabled = !$enabled;
+        // Only set value if there is no config setting or if the value is different from the previous one.
+        if ($oldvalue == false && $disabled) {
+            set_config($settingname, $disabled, 'question');
+            $haschanged = true;
+        } else if ($oldvalue != false && !$disabled) {
+            unset_config($settingname, 'question');
+            $haschanged = true;
+        }
+
+        if ($haschanged) {
+            add_to_config_log($settingname, $oldvalue, $disabled, 'question');
+            \core_plugin_manager::reset_caches();
+        }
+
+        return $haschanged;
+    }
+
     public function is_uninstall_allowed() {
         global $DB;