Merge pull request #273 from assertchris/feature/allow-filter-posts-b…

…y-tag-slug

Allow filter posts by tag (slug)

src/WinkPost.php

@@ -169,6 +169,20 @@ public function scopeAfterPublishDate($query, $date)
         return $query->where('publish_date', '>', $date);
     }
 
+    /**
+     * Scope a query to only include posts that have a specific tag (by slug).
+     *
+     * @param \Illuminate\Database\Eloquent\Builder $query
+     * @param string $slug
+     * @return \Illuminate\Database\Eloquent\Builder
+     */
+    public function scopeTag($query, string $slug)
+    {
+        return $query->whereHas('tags', function ($query) use ($slug) {
+            $query->where('slug', $slug);
+        });
+    }
+
     /**
      * Prepare a date for array / JSON serialization.
      *