Fix spam detector handling of unreadable special characters

Author: tabuna

Diff for: app/Services/SpamDetector.php

@@ -105,6 +105,10 @@ public function hasTooManySpecialCharacters()
             ->squish()
             ->wordCount();
 
+        if($countWords === 0) {
+            return true;
+        }
+
         $diff = ($withSpecialCharacters - $withOutSpecialCharacters) / 2;
 
         // Proportion of special characters in the message

Diff for: tests/Unit/SpamDetectorTest.php

@@ -144,4 +144,10 @@ public function testMessageOneSpecialCharacters(): void
         $spamDetector = new SpamDetector('🔥');
         $this->assertTrue($spamDetector->hasTooManySpecialCharacters());
     }
+
+    public function testMessageSpecialCharacters(): void
+    {
+        $spamDetector = new SpamDetector('✅ 🔤🔤🔤🔤 🔤🔤🔤🔤🔤🔤 ✅ 🔠🔠🔠🔠🔠 🔠 🔠🔠🔠🔠🔠🔠🔠 🔥🔥🔥🔥🔥🔥🔥🔥🔥🔥 🔥🔥🔥🔥🔥 ♦️🔺🔺♦️♦️ ♦️🔺🔺🔺 4️⃣2️⃣5️⃣💲 🔡 🔡🔡🔡🔡 ⚪️⚪️🔴⚪️⚪️🔴 🔴⚪️⚪️ 🔤🔤🔤🔤🔤🔤 🔤 🔤🔤');
+        $this->assertTrue($spamDetector->hasTooManySpecialCharacters());
+    }
 }