Don't include certain terms as hashtags in tweets

References #24

web/modules/custom/opdavies_blog/src/Entity/Node/Post.php

@@ -61,10 +61,19 @@ class Post extends Node implements ContentEntityBundleInterface {
 
   private function convertTermsToHashtags(): string {
     return $this->getTags()
+      ->filter(fn(Term $term) => !$this->tagsToRemove()
+        ->contains($term->label()))
       ->map(fn(Term $term) => $this->convertTermToHashtag($term))
       ->implode(' ');
   }
 
+  private function tagsToRemove(): Collection {
+    // TODO: Move these values into configuration/settings.php.
+    return new Collection([
+      'Drupal Planet',
+    ]);
+  }
+
   private function convertTermToHashtag(Term $tag): string {
     $tagName = strtolower($tag->label());
     $tagName = "#{$tagName}";

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

@@ -67,6 +67,32 @@ final class PostTest extends EntityKernelTestBase {
     $this->assertSame($expected, $post->toTweet());
   }
 
+  /** @test */
+  public function certain_terms_are_not_added_as_hashtags(): void {
+    /** @var Post $post */
+    $post = Node::create([
+      'field_tags' => [
+        Term::create(['vid' => 'tags', 'name' => 'Drupal']),
+        Term::create(['vid' => 'tags', 'name' => 'Drupal Planet']),
+        Term::create(['vid' => 'tags', 'name' => 'PHP']),
+      ],
+      'status' => NodeInterface::PUBLISHED,
+      'title' => 'Drupal Planet should not be added as a hashtag',
+      'type' => 'post',
+    ]);
+    $post->save();
+
+    $expected = <<<EOF
+    Drupal Planet should not be added as a hashtag
+
+    http://localhost/node/1
+
+    #drupal #php
+    EOF;
+
+    $this->assertSame($expected, $post->toTweet());
+  }
+
   protected function setUp() {
     parent::setUp();