Style/GuardClause triggered for complex elsif conditions

[amw]

The most recent version of RuboCop as well as current git master trigger this GuardClause errors for my if/elsif/else branches. Example file:

def process_file file
  if file.video?
    puts file.video_info
  elsif file.image?
    puts file.image_info
  else
    raise "unsupported file type"
  end

  puts file.general_info
end

Output:

asd.rb:4:3: C: Use a guard clause instead of wrapping the code inside a conditional expression.
  elsif file.image?
  ^^^^^

I think it doesn't make sense. The guard condition would have to be very complex, the more complex the more elsif clauses there are. Below is – in my opinion – worse code that Rubocop likes:

def process_file file
  raise "unsupported file type" unless file.video? || file.image?

  if file.video?
    puts file.video_info
  elsif file.image?
    puts file.image_info
  end

  puts file.general_info
end

If this looks OK to you then consider the same example, but with 5 elsif checks.

[madwort]

Using case will pass the cop:

def process_file file
  case  
  when file.video?
    puts file.video_info
  when file.image?
    puts file.image_info
  else
    raise "unsupported file type"
  end

  puts file.general_info
end

[alexdowad]

Using case will pass the cop:

That's true, but is the behavior of this cop desirable as re: elsif?

[madwort]

No, I think @amw 's original example is preferable when using elsif

[alexdowad]

This cop already has a clause which catches elsifs, but it does it wrongly.