Code tidy.

renderer.php

@@ -33,7 +33,7 @@ defined('MOODLE_INTERNAL') || die();
 class qtype_stack_renderer extends qtype_renderer {
 
     public function formulation_and_controls(question_attempt $qa, question_display_options $options) {
-        /* @var qtype_stack_question $question */
+        /* Return type should be @var qtype_stack_question $question. */
         $question = $qa->get_question();
 
         $response = $qa->get_last_qt_data();
@@ -99,9 +99,8 @@ class qtype_stack_renderer extends qtype_renderer {
 
         // Initialise automatic validation, if enabled.
         if (stack_utils::get_config()->ajaxvalidation) {
-            // Once we cen rely on everyone being on a Moodle version that
-            // includes the fix for MDL-65029 (3.5.6+, 3.6.4+, 3.7+)
-            // we can remove this if and just call the method.
+            // Once we cen rely on everyone being on a Moodle version that includes the fix for
+            // MDL-65029 (3.5.6+, 3.6.4+, 3.7+) we can remove this if and just call the method.
             if (method_exists($qa, 'get_outer_question_div_unique_id')) {
                 $questiondivid = $qa->get_outer_question_div_unique_id();
             } else {

stack/cas/ast.container.class.php

@@ -74,7 +74,8 @@ class stack_ast_container extends stack_ast_container_silent implements cas_late
      */
     private $displayvalue;
 
-    protected function __construct() {}
+    protected function __construct() {
+    }
 
     public function add_errors($err) {
         if ('' == trim($err)) {

stack/cas/ast.container.silent.class.php

@@ -237,7 +237,8 @@ class stack_ast_container_silent implements cas_evaluatable {
         return $astc;
     }
 
-    protected function __construct() {}
+    protected function __construct() {
+    }
 
     public function set_keyless(bool $key=true) {
         $this->keyless = $key;

stack/cas/parsingrules/801_singleton_numeric.filter.php

@@ -121,7 +121,6 @@ class stack_ast_filter_801_singleton_numeric implements stack_cas_astfilter_para
             return $ast;
         }
 
-
         // The non trivial bit of identifying a power form representation.
         // 10^1 is also one, i.e. matissa being 1 and omitted is to be noted.
         $m = null;