It's very easy to forget to add `require 'rails_helper'` at the top of every core/plugin spec file, and omissions can cause some very confusing/sporadic errors.
By setting this flag in `.rspec`, we can remove the need for `require 'rails_helper'` entirely.
A simplified version of the logic used in the function before my fix is as follow:
```ruby
result = []
things = [0,1,2,3]
max_values = 2
every = (things.size.to_f / max_values).ceil
things.each_with_index do |t, index|
next unless (t % every) === 0
result << t
end
p result # [0, 2]
# 3 doesn’t get included
```
The problem is that if you get unlucky two times you won't get last tuple(s) and might get a very erroneous date.
Double unlucky:
- last tuple index % computed every !== 0 and you don't get the last tuple
- the last tuple is related to a post with a very different date than the previous tuples (on year difference in our case)
