As mentioned in commits 5311daadf and bb958daf0, using links combined
with JavaScript to generate POST requests to the server has a few
issues.
We're also improving the keyboard access. Previously, the links were
focusable and clickable with the keyboard. Now we're disabling the
buttons when voting isn't allowed.
Since these elements can no longer be focused, we're adding an element
with `tabindex="0"` so the "participation not allowed" message is shown,
like we do in most places.
Note we're slightly changing one test because now when hovering over the
button on Chrome, the "participation not allowed" text isn't shown; it's
only shown when hovering on the parts of the `div.ballot` element
outside the button. Since we're already rewriting the behavior of the
"participation not allowed" text in a different pull request, we aren't
going to fix this behavior.
These tests were supposed to check the link to vote is hidden when users
don't have permission to vote. However, they aren't testing that, since
the `visible: false` option also matches visible elements. The links are
actually considered visible since they're displayed by the browser;
there's just another element on top of them.
Using `obscured: true` instead of `visible: false` solves the issue.
However, while the `obscured` option is true when the element is hidden
by another element, it's also true when the element is not currently
visible in the browser window, so in some cases we need to scroll so the
condition is effective.
We were very inconsistent regarding these rules.
Personally I prefer no empty lines around blocks, clases, etc... as
recommended by the Ruby style guide [1], and they're the default values
in rubocop, so those are the settings I'm applying.
The exception is the `private` access modifier, since we were leaving
empty lines around it most of the time. That's the default rubocop rule
as well. Personally I don't have a strong preference about this one.
[1] https://rubystyle.guide/#empty-lines-around-bodies
