JavaScript is used by about 98% of web users, so by testing without it
enabled, we're only testing that the application works for a very
reduced number of users.
We proceeded this way in the past because CONSUL started using Rails 4.2
and truncating the database between JavaScript tests with database
cleaner, which made these tests terribly slow.
When we upgraded to Rails 5.1 and introduced system tests, we started
using database transactions in JavaScript tests, making these tests much
faster. So now we can use JavaScript tests everywhere without critically
slowing down our test suite.
We were repeating the same code over and over (with a few variants) to
setup tests which require an administrator. We can use a tag and
simplify the code.
This rule was added in Rubocop 0.89.0. However, there are some false
positives when we don't use interpolation but simply concatenate in
order to avoid long lines. Even if there weren't false positives, there
are places where we concatenate to emphasize the point that we're adding
a certain character to a text.
We might reconsider this rule in the future, since we generally prefer
interpolation over concatenation.
