In Rails 5.1, calling `travel_to` inside another `travel_to` block will
result in a RuntimeError:
> Calling `travel_to` with a block, when we have previously already made
> a call to `travel_to`, can lead to confusing time stubbing.
Due to technical issues, sometimes users voted in booths and their vote
couldn't be added to the database. So we're including them in the users
with no demographic data.
We need a way to manually expire the cache for a budget or poll without
expiring the cache of every budget or poll.
Using the `updated_at` column would be dangerous because most of the
times we update a budget or a poll, we don't need to regenerate their
stats.
We've considered adding a `stats_updated_at` column to each of these
tables. However, in that case we would also need to add a similar column
in the future to every process type whose stats we want to generate.
If users participated and were hidden after participating, we should
still count them in the participants stats.
In the tests, we set users' `hidden_at` attribute before they vote.
Although in real life they would vote first and then they would be
hidden, I've written the tests like this for the sake of simplicity.
It will make it far easier to call other methods on the stats object,
and we're already caching the methods.
We had to remove the view fragment caching because the stats object
isn't as easy to cache. The good thing about it is the view will
automatically be updated when we change logic regarding which stats to
show, and the methods taking long to execute are cached in the model.
For now we think showing them would be showing too much data and it
would be a bit confusing.
I've been tempted to just remove the view and keep the methods in the
model in case they're used by other institutions using CONSUL. However,
it's probably better to wait until we're asked to re-implement them, and
in the meantime we don't maintain code nobody uses. The code wasn't that
great to start with (I know it because I wrote it).
While we already had "one test to rule all stats", testing each method
individually makes reading, adding and changing tests easier.
Note we need to make all methods being tested public. We could also test
them using methods like `stats.generate[:total_valid_votes]` instead of
`stats.total_valid_votes`, but then the tests would be more difficult to
read.
Adding the option to assign a poll to a poll recount factory meant we
didn't need to create so much data.
Also note we're removing the `create(:poll_voter, origin: "booth")`
code, since it isn't used in the stats calculations.
