First argument in form cannot contain nil or be empty - Rails 4

Question

I receive this error with my contact form in rails:

First argument in form cannot contain nil or be empty

View:

Answer 1

I had the same problem. I have a Comment model, a CommentsController, a 'show' action and a 'show' view for the comment. I also have a '_show' partial rendered inside the 'show' view with following local:

:locals => {:comment => @comment}

and inside the '_show' partial I have a

<%= form_for(comment, :remote => true) do |f| %>

which troughs the "First argument in form cannot contain nil or be empty". I only could solve the problem by renaming the local:

:locals => {:new_comment => @comment}

and within the partial:

<%= form_for(new_comment, :remote => true) do |f| %>

It seems using the same name for the Model and the partial local caused some conflict for me.