If-else vs case

[tejasbubane]

This came up in a PR discussion: rubocop/rubocop#7153 (comment)

Suggestion is to prefer case over if-elsif-...-else

# bad
if arg == :foo
  foo_action
elsif arg == :bar
  bar_action
elsif arg == :baz
  baz_action
else
  final_action
end

# good
case arg
when :foo
  foo_action
when :bar
  bar_action
when :baz
  baz_action
else
  final_action
end

[bbatsov]

I thought we had this already. After all it's one of the primary usecases of case, so it makes sense to recommend it.