Our original interface to vote in a poll had a few issues:
* Since there was no button to send the form, it wasn't clear that
selecting an option would automatically store it in the database.
* The interface was almost identical for single-choice questions and
multiple-choice questions, which made it hard to know which type of
question we were answering.
* Adding other type of questions, like open answers, was hard since we
would have to add a different submit button for each answer.
So we're now using radio buttons for single-choice questions and
checkboxes for multiple-choice questions, which are the native controls
designed for these purposes, and a button to send the whole form.
Since we don't have a database table for poll ballots like we have for
budget ballots, we're adding a new `Poll::WebVote` model to manage poll
ballots. We're using WebVote instead of Ballot or Vote because they
could be mistaken with other vote classes.
Note that browsers don't allow removing answers with radio buttons, so
once somebody has voted in a single-choice question, they can't remove
the vote unless they manually edit their HTML. This is the same behavior
we had before commit 7df0e9a96.
As mentioned in c2010f975, we're now adding the `ChangeByZero` rubocop
rule, since we've removed the test that used `and change`.
Until now, we've stored the text of the answer somebody replied to. The
idea was to handle the scenarios where the user voters for an option but
then that option is deleted and restored, or the texts of the options
are accidentally edited and so the option "Yes" is now "Now" and vice
versa.
However, since commit 3a6e99cb8, options can no longer be edited once
the poll starts, so there's no risk of the option changing once somebody
has voted.
This means we can now store the ID of the option that has been voted.
That'll also help us deal with a bug introduced int 673ec075e, since
answers in different locales are not counted as the same answer. Note we
aren't dealing with this bug right now.
We're still keeping (and storing) the answer as well. There are two
reasons for that.
First, we might add an "open answer" type of questions in the future and
use this column for it.
Second, we've still got logic depending on the answer, and we need to be
careful when changing it because there are existing installations where
the answer is present but the option_id is not.
Note that we're using `dependent: nullify`. The reasoning is that, since
we're storing both the option_id and the answer text, we can still use
the answer text when removing the option. In practice, this won't matter
much, though, since we've got a validation rule that makes it impossible
to destroy options once the poll has started.
Also note we're still allowing duplicate records when the option is nil.
We need to do that until we've removed every duplicate record in the
database.
Note that, when taking votes from an erased user, since poll answers
don't belong to poll voters, we were not migrating them in the
`take_votes_from` method (and we aren't migrating them now either).
We were checking we didn't have more votes than allowed in the case of
questions with multiple answers, but we weren't checking it in the case
of questions with a single answer. This made it possible to create more
than one answer to the same question. This could happen because the
method `find_or_initialize_user_answer` might initialize two answers in
different threads, due to a race condition.
Having a class named `Poll::Question::Answer` and another class named
`Poll::Answer` was so confusing that no developer working on the project
has ever been capable of remembering which is which for more than a few
seconds.
Furthermore, we're planning to add open answers to polls, and we might
add a reference from the `poll_answers` table to the
`poll_question_answers` table to property differentiate between open
answers and closed answers. Having yet another thing named answer would
be more than what our brains can handle (we know it because we did this
once in a prototype).
So we're renaming `Poll::Question::Answer` to `Poll::Question::Option`.
Hopefully that'll make it easier to remember. The name is also (more or
less) consistent with the `Legislation::QuestionOption` class, which is
similar.
We aren't changing the table or columns names for now in order to avoid
possible issues when upgrading (old code running with the new database
tables/columns after running the migrations but before deployment has
finished, for instance). We might do it in the future.
I've tried not to change the internationalization keys either so
existing translations would still be valid. However, since we have to
change the keys in `activerecord.yml` so methods like
`human_attribute_name` keep working, I'm also changing them in places
where similar keys were used (like `poll_question_answer` or
`poll/question/answer`).
Note that it isn't clear whether we should use `option` or
`question_option` in some cases. In order to keep things simple, we're
using `option` where we were using `answer` and `question_option` where
we were using `question_answer`.
Also note we're adding tests for the admin menu component, since at
first I forgot to change the `answers` reference there and all tests
passed.
In case we receive consecutive requests we are locking the poll author record
until the first request transaction ends, so the author answers count during
subsequent requests validations is up to date.
Up until now, we were assuming the voter was valid, but were not raising
an exception if it wasn't. And in the user interface everything seemed
to be working properly.
We were having this issue when skipping verification, when there could
be voters without a document number, which would be considered invalid.
Raising an exception when failing to save the voter and making sure the
answer and the voter are saved inside a transaction solves the problem.
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
We barely use this trait. In the votation type spec we're probably using
it wrong, and in the answer spec we assume one of the answers is going
to be "Yes".
The name `yes_no` is more expressive, since it makes it clear what the
answers are.