reduce unneed query when post without attachements. (#1907)

* reduce unneed query when post without attachements.

This commit reduce following query:

```
 MediaAttachment Load (0.9ms)  SELECT "media_attachments".* FROM "media_attachments" WHERE "media_attachments"."status
_id" IS NULL AND 1=0 ORDER BY id asc
```

* fixed for more simple changes.

diff --git a/app/services/post_status_service.rb b/app/services/post_status_service.rb
index ec2b90e075c19fc4fee110058109c40ca47f5bcd..00af28edde78642cc784c4e046ee202467487253 100644 (file)
--- a/app/services/post_status_service.rb
+++ b/app/services/post_status_service.rb
@@ -36,7 +36,7 @@ class PostStatusService < BaseService
   private
 
   def validate_media!(media_ids)
-    return if media_ids.nil? || !media_ids.is_a?(Enumerable)
+    return if media_ids.blank? || !media_ids.is_a?(Enumerable)
 
     raise Mastodon::ValidationError, I18n.t('media_attachments.validations.too_many') if media_ids.size > 4