Upgrading from 3.0.3 -> 3.1.0 broke our checkbox inputs

[nickmalcolm]

We use simple_form and the bitmask_attributes gem to let users save their email preferences.

In 3.0.3, checkboxes are checked as expected. You can check & uncheck options, and have them saved properly. After upgrading the simple_form gem to 3.1.0, checkboxes which should be checked aren't. (Flicking between the versions makes the bug appear and disappear, so I'm fairly sure it's something here).

I can't see anything in the CHANGELOG deprecations to indicate anything that might have changed? Perhaps we've always been doing it wrong, and it's only just become an issue?

I'm not sure the best place to start debugging this, but hopefully we can figure this out.

The model

class Customer < ActiveRecord::Base
  ...
  bitmask :email_preferences, :as => [:weekly_digest, :daily_digest, etc]
end

The form

  <%= simple_form_for current_customer do |f| %>
    <div class="form-inputs">
      <%= f.input :email_preferences, as: :check_boxes, collection: Customer.values_for_email_preferences, label: " " %>
    </div>

    <div class="form-actions">
      <%= f.button :submit, "Save Notifications" %>
    </div>
  <% end %>

[nickmalcolm]

If it helps, here's how the HTML changes. Aside from losing checked="checked", looks like class="checkbox" has moved into a new wrapping span.

Old

<div class="form-inputs">
  <div class="input check_boxes optional customer_email_preferences">
    <label>
      <label class="checkbox">
        <input checked="checked" class="check_boxes optional" id="customer_email_preferences_weekly_digest" name="customer[email_preferences][]" type="checkbox" value="weekly_digest">
        Weekly Digest
      </label>
      <label class="checkbox">
        <input class="check_boxes optional" id="customer_email_preferences_daily_digest" name="customer[email_preferences][]" type="checkbox" value="daily_digest">
        Daily Digest
      </label>
      <input name="customer[email_preferences][]" type="hidden" value="">
    </label>
  </div>
</div>

New

<div class="form-inputs">
  <div class="input check_boxes optional customer_email_preferences">
    <label>
      <span class="checkbox">
        <label for="customer_email_preferences_weekly_digest">
          <input class="check_boxes optional" id="customer_email_preferences_weekly_digest" name="customer[email_preferences][]" type="checkbox" value="weekly_digest">
          Weekly Digest
        </label>
      </span>
      <span class="checkbox">
        <label for="customer_email_preferences_daily_digest">
          <input class="check_boxes optional" id="customer_email_preferences_daily_digest" name="customer[email_preferences][]" type="checkbox" value="daily_digest">
          Daily Digest
        </label>
      </span>
      <input name="customer[email_preferences][]" type="hidden" value="">
    </label>
  </div>
</div>

[rafaelfranca]

Can you please provide a sample application that reproduces the error?

[nickmalcolm]

Hey Rafael,

Short answer: nope, which is embarrassing! Pretty sure it's to do with this: #828

Using value_method: :to_sym "fixes" the problem, but I'll need to figure out the actual cause. For now I'll just stick with 3.0.3. I'll reopen this if I can get a sample app going.

Sorry for the bother - hopefully this helps other people experiencing the same issue!