activesupport on ruby 2.6 | using 1.hour in step gets slow

[artisr]

Steps to reproduce

use ruby 2.6 & activesupport 5.2.2

(1...72000).step(1.hour).each { |x| puts x }
or any other duration used in step

Expected behavior

be constantly fast

Actual behavior

gets exponentially slower

System configuration

rails 5.2
ruby 2.6

[artisr]

its creating a new duration all the time
https://github.com/rails/rails/blob/5-2-stable/activesupport/lib/active_support/duration.rb#L245

using .step(1.hour.to_i) on duration fixes things, so no biggy, but maybe someone wants to take a peek :)

[eileencodes]

Hey @artisr does this happen with Rails 5.2 Ruby 2.5 as well?

[artisr]

@eileencodes no, on ruby 2.5 its instant / no slowdowns.
I guess its because ruby 2.6 has the new Enumerator::ArithmeticSequence

Just to make it clear, its not limited to 1.hour its to any duration used in step

[brian-kephart]

I'm experiencing this issue as well, with the same versions.

[brian-kephart]

My code uses a range of times, like this:

(Time.parse('10am').to_i..Time.parse('9pm').to_i).step(30.minutes).each do |time|
  puts time
end

The symptoms are all the same as @artisr, I just wanted to point out the issue occurs with multiple range types.