Issue #6910 has been updated by tenderlovemaking (Aaron Patterson).

Status changed from Assigned to Rejected

I've pushed a gem for people that want to upgrade to Ruby 2.0.0, but still have Syck's YAML:

  https://rubygems.org/gems/syck

Since libyaml does the actual YAML parsing, we would either have to include syck with psych, or ship libyaml with ruby and modify it's parser.  I think the gem option is the best route.  People can still use it to parse old YAML.
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Feature #6910: Loading syck's broken yaml with psych
https://bugs.ruby-lang.org/issues/6910#change-31779

Author: naruse (Yui NARUSE)
Status: Rejected
Priority: Normal
Assignee: tenderlovemaking (Aaron Patterson)
Category: ext
Target version: 2.0.0


You know, syck outputs wrong yaml.
For example, syck works as following:

ruby-1.9.2 > ["\u3042",Time.at(0).to_s].to_yaml
=> "--- \n- \"\\xE3\\x81\\x82\"\n- 1970-01-01 09:00:00 +09:00\n"

It should be

ruby-1.9.3 > ["\u3042",Time.at(0).to_s].to_yaml
=> "---\n- ???\n- '1970-01-01 09:00:00 +0900'\n"

syck's dump of Unicode string is interpreted as "\u00E3\u0081\u0082".
syck's dump of Time like string is interpreted as Time.
It is hard to migrate old data to new and correct data, so it is useful if psych has a such compatibility option.


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