Fix issue with button_to's to_form_params

[gtyanchev]

Summary

I've encountered an exception while using the button_to helper. The code goes like this:

button_to "Submit", clients_path, method: :post, 
           params: { name: "Georgi", user: { email: "georgi@example.com" } }

And it's expected that it will generate a form with hidden fields:

<input type="hidden" name="name" value="Georgi" />
<input type="hidden" name="user[email]" value="georgi@example.com" />

But instead it raises:

ArgumentError: comparison of Symbol with String failed 

This happens because when the names for the hidden fields are extracted the name param is mapped to

{ name: :name, value: "Georgi" } 

and the user param is mapped to

{ name: "user[email]", value: "georgi@example.com" }

and after that these hashes are sorted by name, which triggers a comparison between :name and "user[email]" and so an exception is raised.

The same exception is also raised if we give a params hash with symbol and string key, for example:

button_to "Submit", clients_path, method: :post, 
           params: { :name => "Georgi", "email" => "georgi@example.com" }

The most unintrusive fix a can think of is to turn all hidden field names to string in the comparison block.

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[gmcgibbon]

Still reproducible in 6.0.0.alpha. Seems like a reasonable change to ensure proper sorting in #to_form_params.

[gmcgibbon]

I think it would make more sense to cast to a string a few lines before in the case's else block: params << { name: namespace.to_s, value: attribute.to_param }

[rafaelfranca]

Agree

[rafaelfranca]

Could you apply the change suggested by @gmcgibbon?

[rafaelfranca]

Agree

[gtyanchev]

The suggested changes are applied.

[kaspth]

Thanks! Needs a rebase for the changelog, then I'll merge 😄

[gtyanchev]

Rebased 🎉