syck seems to not work on ruby 2.2.0p0 (2014-12-25 revision 49005) [i686-linux]

[ghost]

Hello,

This is an error possibly on ruby 2.2.0p0.
syck works perfectly fine on ruby 2.1.5 for me.

The error I get is when I try to do this here:

YAML::ENGINE.yamler

I used this before to set syck.

When I do this, though, I immediately get this error:

NameError: uninitialized constant Psych::Syck::ENGINE

Both psych and syck were required before I tried the above.

I assume something has changed in between these two ruby
versions but I am not quite sure how to trace back this error.

Thanks.

[paneq]

+1.

I was wondering whether YAML = Syck is the new way to use Syck instead of Psych globally?

[nicolai86]

+1.

Any ideas on how to work around this issue for now, without downgrading your ruby?

[fredv]

Hi Aaron @tenderlove,
this seems to be because of the removal of YAML::ENGINE in psych. (see https://github.com/tenderlove/psych/blob/24ff7855ca2f62e59fc951fa30b225f42369c2a2/CHANGELOG.rdoc, Sun May 25 11:35:41 2014 Zachary Scott e@zzak.io * test/psych/*: YAML::ENGINE was removed in [Bug #8344])

Is there an alternative way? Maybe the constant overwriting part could be optional or another version switch included?

This should be a legacy problem, for our case it's about handling different parsing behavior of psych and syck (I think I remember some cases where syck can parse fairly valid structures from technically invalid YAML ... which is awkward on its own I guess).

We will work around this by not using syck in this case as fallback, I think.

Thank you for putting together both libraries!

[jcabasc]

Is there any update on this? Still having the same with ruby-2.2.0 or greater.

[hsbt]

Hi, If you submit a patch of this issue, I will merge it.

[dbackeus]

+1

[ccutrer]

You should be able to check YAML.name. In regular ruby 2.2, you get "Psych", but with the syck gem you get "Syck".

[illtellyoulater]

So, is it still possible to use the "syck" engine with Ruby 2.2?

In some old source code I had this:

YAML::ENGINE.yamler='syck'  # using old version of engine will avoid dumping to binary format 

But now I can't quite understand what I meant myself? :)

Given that it seems I can't use "syck" anymore with Ruby 2.2, can I just remove YAML::ENGINE.yamler='syck' and it will still be able to parse the old "syck" serialized data?

[GCinellu]

+1

[courtenay]

this appears to be broken again on 2.3.x

irb
irb(main):001:0> RUBY_VERSION
=> "2.3.4"
irb(main):002:0> require 'yaml'
=> true
irb(main):003:0> require 'syck'
=> true
irb(main):004:0> YAML::ENGINE
NameError: uninitialized constant Syck::ENGINE
	from (irb):4
	from /Users/courtenay/.rbenv/versions/2.3.4/bin/irb:11:in `<main>'

looking at the code for engine_manager should be possible to just require that, but..

irb(main):006:0> require 'yaml/engine_manager'
/Users/courtenay/.rbenv/versions/2.3.4/lib/ruby/gems/2.3.0/gems/syck-1.2.0/lib/yaml/engine_manager.rb:70: warning: already initialized constant Syck::ENGINE
/Users/courtenay/.rbenv/versions/2.3.4/lib/ruby/gems/2.3.0/gems/syck-1.2.0/lib/yaml/engine_manager.rb:49: warning: previous definition of ENGINE was here
=> true
irb(main):007:0> YAML::ENGINE
=> #<Syck::EngineManager:0x007fb4d993cc78 @yamler=nil>
irb(main):008:0> YAML::ENGINE.yamler
=> nil
irb(main):009:0> YAML::ENGINE.yamler = 'syck'
NameError: constant Syck::Object::YAML not defined
	from /Users/courtenay/.rbenv/versions/2.3.4/lib/ruby/gems/2.3.0/gems/syck-1.2.0/lib/yaml/engine_manager.rb:34:in `remove_const'
	from /Users/courtenay/.rbenv/versions/2.3.4/lib/ruby/gems/2.3.0/gems/syck-1.2.0/lib/yaml/engine_manager.rb:34:in `yamler='
	from /Users/courtenay/.rbenv/versions/2.3.4/lib/ruby/gems/2.3.0/gems/syck-1.2.0/lib/yaml/engine_manager.rb:33:in `class_eval'
	from /Users/courtenay/.rbenv/versions/2.3.4/lib/ruby/gems/2.3.0/gems/syck-1.2.0/lib/yaml/engine_manager.rb:33:in `yamler='
	from (irb):9
	from /Users/courtenay/.rbenv/versions/2.3.4/bin/irb:11:in `<main>'

it appears that this fixes it somewhat in engine_manager

-      Object.class_eval <<-eorb, __FILE__, __LINE__ + 1
+     ::Object.class_eval <<-eorb, __FILE__, __LINE__ + 1

i'm not sure if this is right though :)

[mikhailov]

is there a plan to get it working with Ruby 2.3.5?

[nuritnt]

any news on this?

[hsbt]

Nothing. I always welcome your patch.

[intrip]

is there a plan to get it working with Ruby 2.3.5?

It works with Ruby 2.3.5, when you require "syck" the YAML parser is automatically replaced by syck.