Cumulative Drupal 9 Compatibility Patches.

Cumulative Drupal 9 Compatibility Patches.

This MR combines the Drupal 9 compatibility patch from:

https://www.drupal.org/project/ms_ajax_form_example/issues/3117909#comment-13752939

with a patch to the core_version_requirement in info.yml allowing the module to be installed on Drupal 9.

It is useful to have an issue fork for Drupal 9 compatibility, rather than simply a patch, because:

In short, you can't use a patch to tell Composer that a Drupal 8 module is compatible with Drupal 9.

Source: https://www.mediacurrent.com/blog/how-fix-catch-22-problem-drupal-9-fixes-composer/

Adding Issue Fork as a Composer repository:

To use this issue fork as a transitional D9-compatible package in your project, modify your composer.json:

    "repositories": {
        "drupal/ms_ajax_form_example": {
            "type": "vcs",
            "url": "https://git.drupalcode.org/issue/ms_ajax_form_example-3117909"
        },
        "drupal": {
          "type": "composer",
          "url": "https://packages.drupal.org/8",
          "exclude": ["drupal/ms_ajax_form_example"]
        },

Requiring the patched package from the Issue Fork:

Execute the following command in a terminal:

$ composer require drupal/ms_ajax_form_example:dev-3117909-call-to-deprecated

or manually add the requirement to composer.json:

    "require": {
        "drupal/ms_ajax_form_example": "dev-3117909-call-to-deprecated",

Credit due, mainly, to Benji Fisher via: https://www.drupal.org/project/views_url_alias/issues/3142138#comment-14177409

NOTE:

Not yet tested with Drupal 8. You can help the Drupal community by testing this!

Not yet tested with Drupal 9. You can help the Drupal community by testing this!

Closes #3117909

src/Form/MultiStepExampleForm.php

@@ -6,6 +6,7 @@ use Drupal\Core\Ajax\AjaxResponse;
 use Drupal\Core\Ajax\HtmlCommand;
 use Drupal\Core\Form\FormBase;
 use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Messenger\MessengerInterface;
 use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\ms_ajax_form_example\Manager\StepManager;
 use Drupal\ms_ajax_form_example\Step\StepsEnum;
@@ -39,12 +40,20 @@ class MultiStepExampleForm extends FormBase {
    */
   protected $stepManager;
 
+  /**
+   * The Messenger service.
+   *
+   * @var \Drupal\Core\Messenger\MessengerInterface
+   */
+  protected $messenger;
+
   /**
    * {@inheritdoc}
    */
-  public function __construct() {
+  public function __construct(MessengerInterface $messenger = NULL) {
     $this->stepId = StepsEnum::STEP_ONE;
     $this->stepManager = new StepManager();
+    $this->messenger = $messenger;
   }
 
   /**
@@ -119,7 +128,7 @@ class MultiStepExampleForm extends FormBase {
   public function loadStep(array &$form, FormStateInterface $form_state) {
     $response = new AjaxResponse();
 
-    $messages = drupal_get_messages();
+    $messages = $this->messenger()->all();
     if (!empty($messages)) {
       // Form did not validate, get messages and render them.
       $messages = [