Console error for custom craftings with only air in the middle

Hello, i found this very annoying error, it will appear if you try to make a custom recipe with only air in the middle slots

Here is the error: https://paste.md-5.net/ufudivufol.coffeescript

And here is an example crafting causing the error: https://paste.md-5.net/cetawoceqi.rb

Can someone look into it? it's spams in console after every reload