Restrict allowed blocks to paragraph, heading and columns

[MAILPOET-5365]

mailpoet/lib/EmailEditor/Core/EmailEditor.php

@@ -7,8 +7,11 @@ namespace MailPoet\EmailEditor\Core;
  * See register_post_type for details about EmailPostType args.
  */
 class EmailEditor {
+  private const ALLOWED_BLOCK_TYPES = ['core/paragraph', 'core/heading', 'core/column', 'core/columns'];
+
   public function initialize(): void {
     $this->registerEmailPostTypes();
+    add_filter('allowed_block_types_all', [$this, 'setAllowedBlocksInEmails'], 100, 2);
   }
 
   private function registerEmailPostTypes() {
@@ -40,4 +43,17 @@ class EmailEditor {
       'show_in_rest' => true, // Important to enable Gutenberg editor
     ];
   }
+
+  /**
+   * @param string[]|bool $allowedBlockTypes
+   * @param \WP_Block_Editor_Context $blockEditorContext
+   * @return array|bool
+   */
+  public function setAllowedBlocksInEmails($allowedBlockTypes, \WP_Block_Editor_Context $blockEditorContext) {
+    $emailPostTypes = array_column($this->getPostTypes(), 'name');
+    if (!$blockEditorContext->post || !in_array($blockEditorContext->post->post_type, $emailPostTypes, true)) {
+      return $allowedBlockTypes;
+    }
+    return self::ALLOWED_BLOCK_TYPES;
+  }
 }

mailpoet/tests/integration/EmailEditor/Core/EmailEditorTest.php

@@ -3,19 +3,47 @@
 namespace MailPoet\EmailEditor\Core;
 
 class EmailEditorTest extends \MailPoetTest {
-  public function testItRegistersHookedCustomPostTypes() {
+  /** @var EmailEditor */
-    $callback = function ($postTypes) {
+  private $emailEditor;
+
+  /** @var callable */
+  private $postRegisterCallback;
+
+  public function _before() {
+    parent::_before();
+    $this->emailEditor = $this->diContainer->get(EmailEditor::class);
+    $this->postRegisterCallback = function ($postTypes) {
       $postTypes[] = [
         'name' => 'custom_email_type',
         'args' => [],
       ];
       return $postTypes;
     };
-    add_filter('mailpoet_email_editor_post_types', $callback);
+    add_filter('mailpoet_email_editor_post_types', $this->postRegisterCallback);
-    $emailEditor = $this->diContainer->get(EmailEditor::class);
+    $this->emailEditor->initialize();
-    $emailEditor->initialize();
+  }
+
+  public function testItRegistersCustomPostTypeAddedViaHook() {
     $postTypes = get_post_types();
     $this->assertArrayHasKey('custom_email_type', $postTypes);
-    remove_filter('mailpoet_email_editor_post_types', $callback);
+  }
+
+  public function testItRestrictsAllowedBlockTypes() {
+    $noEmailContext = new \WP_Block_Editor_Context();
+    $blockTypes = get_allowed_block_types($noEmailContext);
+    expect($blockTypes)->equals(true); // true means all blocks are allowed
+
+    $noEmailContext = new \WP_Block_Editor_Context($settings = ['post' => (object)['post_type' => 'custom_email_type']]);
+    $blockTypes = get_allowed_block_types($noEmailContext);
+    expect($blockTypes)->contains('core/paragraph');
+    expect($blockTypes)->contains('core/heading');
+    expect($blockTypes)->contains('core/columns');
+    expect($blockTypes)->contains('core/column');
+    expect(count((array)$blockTypes))->equals(4);
+  }
+
+  public function _after() {
+    parent::_after();
+    remove_filter('mailpoet_email_editor_post_types', $this->postRegisterCallback);
   }
 }