Count the number of events from talks

source/_pages/talks.html.twig

@@ -2,10 +2,10 @@
 title: Talks and workshops
 use:
     - talks
-intro_text: |
-    Starting with my first talk in September 2012, I have given 82 presentations and workshops at various conferences and meetups, in-person and remotely, on topics including PHP, Drupal, automated testing, Git, CSS, and systems administration.
 ---
 
+<p>Starting with my first talk in September 2012, I have given {{ get_past_talk_count(data.talks) }} presentations and workshops at various conferences and meetups, in-person and remotely, on topics including PHP, Drupal, automated testing, Git, CSS, and systems administration.</p>
+
 <div class="mt-10">
     <div class="space-y-8">
         {% for talk in data.talks|sort((a,b) => a.sortable_date < b.sortable_date) %}

src/TwigExtension/TalkExtension.php

@@ -17,10 +17,16 @@ final class TalkExtension extends AbstractExtension
         ];
     }
 
-    public function getPastTalkCount(array $talks = []): int
+    public function getPastTalkCount(iterable $talks = []): int
+    {
+        return $this->getEventsFromTalks($talks)->count();
+    }
+
+    private function getEventsFromTalks(iterable $talks): Collection
     {
         $talkCollection = new Collection($talks);
 
-        return $talkCollection->count();
+        return $talkCollection
+            ->flatMap(fn($talk): array => (array) $talk['events']);
     }
 }

tests/TalkExtensionTest.php

@@ -7,9 +7,49 @@ use PHPUnit\Framework\TestCase;
 
 final class TalkExtensionTest extends TestCase
 {
+    private TalkExtension $subject;
+
+    public function setUp(): void
+    {
+        $this->subject = new TalkExtension();
+    }
+
     /** @test */
     public function it_returns_zero_if_there_are_no_talks(): void
     {
-        $this->assertSame(0, (new TalkExtension())->getPastTalkCount([]));
+        $this->assertSame(0, $this->subject->getPastTalkCount([]));
+    }
+
+    /** @test */
+    public function it_counts_a_single_event_from_a_single_talk(): void
+    {
+        $talks = [
+            [
+                'title' => 'Building static sites with Sculpin',
+                'events' => [
+                    '',
+                ]
+            ],
+        ];
+
+        $this->assertSame(1, $this->subject->getPastTalkCount($talks));
+    }
+
+    /** @test */
+    public function it_counts_multiple_events_from_a_single_talk(): void
+    {
+        $this->markTestIncomplete();
+    }
+
+    /** @test */
+    public function it_counts_multiple_events_from_multiple_talks(): void
+    {
+        $this->markTestIncomplete();
+    }
+
+    /** @test */
+    public function it_excludes_future_talks(): void
+    {
+        $this->markTestIncomplete();
     }
 }