Rename and re-organise custom modules

- Rename `opd_talks` to `opdavies_talks`
- Rename `custom` to `opdavies_blog`

web/modules/custom/opdavies_blog/tests/src/Kernel/Entity/Node/PostTest.php

@@ -0,0 +1,45 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\Tests\custom\Kernel\Entity\Node;
+
+use Drupal\KernelTests\Core\Entity\EntityKernelTestBase;
+use Drupal\node\Entity\Node;
+use Drupal\opdavies_blog\Entity\Node\Post;
+
+final class PostTest extends EntityKernelTestBase {
+
+  public static $modules = [
+    // Core.
+    'node',
+
+    // Contrib.
+    'discoverable_entity_bundle_classes',
+
+    // Custom.
+    'opdavies_blog',
+    'opdavies_blog_test',
+  ];
+
+  /** @test */
+  public function it_can_determine_if_a_post_contains_a_tweet(): void {
+    /** @var Post $post */
+    $post = Node::create(['type' => 'post']);
+    $this->assertFalse($post->hasTweet());
+
+    /** @var Post $post */
+    $post = Node::create([
+      'field_has_tweet' => TRUE,
+      'type'  => 'post',
+    ]);
+    $this->assertTrue($post->hasTweet());
+  }
+
+  protected function setUp() {
+    parent::setUp();
+
+    $this->installConfig(['opdavies_blog_test']);
+  }
+
+}