Version#changeset raises a ArgumentError

[igorbozato]

syntax error on line 13, col 1: `'

/home/igorbozato/.rvm/rubies/ree-1.8.7-2011.03/lib/ruby/1.8/yaml.rb:133:in `load'
/home/igorbozato/.rvm/rubies/ree-1.8.7-2011.03/lib/ruby/1.8/yaml.rb:133:in `load'
paper_trail (2.2.9) lib/paper_trail/version.rb:87:in `changeset'
app/views/admin/actions/show.html.erb:45:in `_app_views_admin_actions_show_html_erb__306327435_43834300_0'

[airblade]

Please can you post the YAML in question?

[igorbozato]

--- !map:ActiveSupport::HashWithIndifferentAccess last_sign_in_ip: - 200.205.205.178 - 186.200.37.235 last_sign_in_at: - 2011-08-23 13:41:41 Z - 2011-08-26 22:24:20 Z sign_in_count: - 159 - 160 current_sign_in_ip: - 186.200.37.235 - 200.205.205.178 c

[airblade]

Your YAML seems to be stripped of new lines. Is that correct?

[igorbozato]

Sorry, I get it using a ERB page, that is from terminal:

ree-1.8.7-2011.03 :002 > version.object_changes
 => "--- !map:ActiveSupport::HashWithIndifferentAccess \nlast_sign_in_ip: \n- 200.205.205.178\n- 186.200.37.235\nlast_sign_in_at: \n- 2011-08-23 13:41:41 Z\n- 2011-08-26 22:24:20 Z\nsign_in_count: \n- 159\n- 160\ncurrent_sign_in_ip: \n- 186.200.37.235\n- 200.205.205.178\nc" 

[igorbozato]

From the db console:

mysql> select object_changes from versions where id = 3347;
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| object_changes                                                                                                                                                                                                                                                  |
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| --- !map:ActiveSupport::HashWithIndifferentAccess 
last_sign_in_ip: 
- 200.205.205.178
- 186.200.37.235
last_sign_in_at: 
- 2011-08-23 13:41:41 Z
- 2011-08-26 22:24:20 Z
sign_in_count: 
- 159
- 160
current_sign_in_ip: 
- 186.200.37.235
- 200.205.205.178
c |
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

[airblade]

Thanks for those outputs.

The problem is the YAML engine fails to parse the YAML string (which it generated in the first place).

>> require 'active_support'
>> YAML::load "--- !map:ActiveSupport::HashWithIndifferentAccess \nlast_sign_in_ip: \n- 200.205.205.178\n- 186.200.37.235\nlast_sign_in_at: \n- 2011-08-23 13:41:41 Z\n- 2011-08-26 22:24:20 Z\nsign_in_count: \n- 159\n- 160\ncurrent_sign_in_ip: \n- 186.200.37.235\n- 200.205.205.178\nc"
ArgumentError: syntax error on line 13, col 1: `'
    from /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/yaml.rb:133:in `load'
    from /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/yaml.rb:133:in `load'
    from (irb):12

Unfortunately I have no idea why it fails.

[michaelstalker]

This may be a long shot, but I've had some problems with PaperTrail's compatibility with one of the YAML parsers out there. I switched from psych to syck (or the other way around), and that fixed my problem.

[michaelstalker]

As a follow-up, I had added this to my config/boot.rb file to fix the problem I had:

require 'yaml'
YAML::ENGINE.yamler = 'syck'

[airblade]

@mstalker Thanks for posting that.

[batter]

It appears as though the error being thrown is the result of an errant c character at the end of @igorbozato's YAML string. If you remove the c from the end of the string, and try this:

YAML::load "--- !map:ActiveSupport::HashWithIndifferentAccess \nlast_sign_in_ip: \n- 200.205.205.178\n- 186.200.37.235\nlast_sign_in_at: \n- 2011-08-23 13:41:41 Z\n- 2011-08-26 22:24:20 Z\nsign_in_count: \n- 159\n- 160\ncurrent_sign_in_ip: \n- 186.200.37.235\n- 200.205.205.178\n"

It seems to work fine (with both psych and syck as the parser). Not sure how that c character snuck in there, but I have a feeling this may have been accidental user error or something? At any rate I think it is safe to say that this is an unusual case because others do not seem to be encountering this regularly.

If anyone thinks there is something errant in the PaperTrail code that could have caused this, please let us know and I will try to do a deeper investigation to address this problem. I could see a case for potentially swapping in JSON for the default serializer instead of YAML at some point in the future (perhaps v3.0.0) due to the known confusion surrounding psych and syck with the current Ruby releases.