ArgumentError (wrong number of arguments (given 2, expected 1)) after updating to Ruby 3.0

Question

When I try to update our site to Ruby 3.0.0 I get this error:

ArgumentError (wrong number of arguments (given 2, expected 1))

 % rails console
Loading development environment (Rails 6.1.0)
irb(main):001:0> puts RUBY_VERSION
3.0.0
irb(main):002:0> puts IceCube::VERSION
0.16.3
irb(main):003:0> schedule = IceCube::Schedule.new
=> #<IceCube::Schedule:0x00007fccfe19cfa8 @start_time=2020-12-27 11:14:30 -0800, @all_recurrence_rules=[], @all_exception_rules=[]>
irb(main):004:0> puts schedule.to_ical
Traceback (most recent call last):
        1: from (irb):4:in `<main>'
ArgumentError (wrong number of arguments (given 2, expected 1))

Here are the same commands with Ruby 2.7.2 which work

% rails console
Loading development environment (Rails 6.1.0)
irb(main):001:0> puts RUBY_VERSION
2.7.2
irb(main):002:0> puts IceCube::VERSION
0.16.3
irb(main):003:0> schedule = IceCube::Schedule.new
=> #<IceCube::Schedule:0x00007f9da3128fe8 @start_time=2020-12-27 11:12:50 -0800, @all_recurrence_rules=[], @all_exception_rules=[]>
irb(main):004:0> puts schedule.to_ical
DTSTART;TZID=PST:20201227T111250

What's confusing is that it also works with a plain ruby script with the same gem versions as the first example

% irb
irb(main):001:0> puts RUBY_VERSION
3.0.0
irb(main):002:0> gem 'ice_cube'
irb(main):003:0> require 'ice_cube'
irb(main):004:0> puts IceCube::VERSION
0.16.3
irb(main):005:0> schedule = IceCube::Schedule.new
=> #<IceCube::Schedule:0x00007ff2fb0d5b88 @start_time=2020-12-27 11:11:02 -0800, @all_recurrence_rules=[], @all_exception_rules=[]>
irb(main):006:0> puts schedule.to_ical
DTSTART;TZID=PST:20201227T111102

Does anyone know where I can start to fix this? We're just starting the project and I am hoping to use Ruby 3

Answer 1

TL;DR: ice_cube 0.16.4 has already sorted out these compatibility problems with ruby 3.x, so just upgrade.

---

The issue has to do with how keyword arguments are handled in ruby 3.0 and how ice_cube is passing its arguments to I18n.localize.
So, extracting and simplifying the buggy code, this worked on ruby < 3

RUBY_VERSION # "2.7.2"

def foo(*args)
  bar(*args)
end

def bar(object, locale: nil, format: nil, **options)
  puts "object:#{object}"
  puts "locale:#{locale}"
  puts "format:#{format}"
  puts "options:#{options}"
end

foo('date', format: 'whatever')
# object:date
# locale:
# format:whatever
# options:{}

And from ruby >= 3

RUBY_VERSION # "3.0.0"

def foo(*args)
  bar(*args)
end

def bar(object, locale: nil, format: nil, **options)
  puts "object:#{object}"
  puts "locale:#{locale}"
  puts "format:#{format}"
  puts "options:#{options}"
end

foo('date', format: 'whatever')
# Traceback (most recent call last):
#        16: from /Users/alter/.rbenv/versions/3.0.0/lib/ruby/3.0.0/bundler/cli.rb:24:in `start'
#        15: from /Users/alter/.rbenv/versions/3.0.0/lib/ruby/3.0.0/bundler/vendor/thor/lib/thor/base.rb:485:in `start'
#        14: from /Users/alter/.rbenv/versions/3.0.0/lib/ruby/3.0.0/bundler/cli.rb:30:in `dispatch'
#        13: from /Users/alter/.rbenv/versions/3.0.0/lib/ruby/3.0.0/bundler/vendor/thor/lib/thor.rb:392:in `dispatch'
#        12: from /Users/alter/.rbenv/versions/3.0.0/lib/ruby/3.0.0/bundler/vendor/thor/lib/thor/invocation.rb:127:in `invoke_command'
#        11: from /Users/alter/.rbenv/versions/3.0.0/lib/ruby/3.0.0/bundler/vendor/thor/lib/thor/command.rb:27:in `run'
#        10: from /Users/alter/.rbenv/versions/3.0.0/lib/ruby/3.0.0/bundler/cli.rb:497:in `exec'
#         9: from /Users/alter/.rbenv/versions/3.0.0/lib/ruby/3.0.0/bundler/cli/exec.rb:28:in `run'
#         8: from /Users/alter/.rbenv/versions/3.0.0/lib/ruby/3.0.0/bundler/cli/exec.rb:63:in `kernel_load'
#         7: from /Users/alter/.rbenv/versions/3.0.0/lib/ruby/3.0.0/bundler/cli/exec.rb:63:in `load'
#         6: from /Users/alter/.rbenv/versions/3.0.0/bin/irb:23:in `<top (required)>'
#         5: from /Users/alter/.rbenv/versions/3.0.0/bin/irb:23:in `load'
#         4: from /Users/alter/.rbenv/versions/3.0.0/lib/ruby/gems/3.0.0/gems/irb-1.3.0/exe/irb:11:in `<top (required)>'
#         3: from (irb):11:in `<main>'
#         2: from (irb):3:in `foo'
#         1: from (irb):5:in `bar'
# ArgumentError (wrong number of arguments (given 2, expected 1))

So, the fix I can see is to explicitely passing the parameters to the method:

def foo2(object, **options)
  bar(object, **options)
end

foo2('date', format: 'whatever')
# object:date
# locale:
# format:whatever
# options:{}

Or in terms of the involved module:

module IceCube
  module I18n
    def self.l(object, **options)
      backend.l(object, **options)
    end
  end
end

and send a PR, use your own fork, monkey-patch, whatever works best for you.
But most important, brace yourself to find this issue in a lot of other gems, as the first stable ruby 3 version was just released 2 days ago, so probably you'll have these type of issues with other gems, specially the unmaintained ones. Good luck.