We were inconsistent on this one. I consider it particularly useful when
a method starts with a `return` statement.
In other cases, we probably shouldn't have a guard rule in the middle of
a method in any case, but that's a different refactoring.
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
Naming two variables the same way is confusing at the very least, and
can lead to hard to debug errors. That's why the Ruby interpreter issues
a warning when we do so.
The code `where(id: ids)` is equivalent to `where(id: ids.uniq)`.
Since Rails 5 uses `distinct` instead of `uniq` and in most cases where
we use `uniq` with `pluck` we should simply remove the `uniq` call (as
done in this commit), we're also removing the `Rails/UniqBeforePluck`
rubocop rule.
