Single-escaped strings with '' should be valid

[irony]

When trying to parse this valid string

key:
value: 'Let''s encode this'

It throws this error:

Error: hash not properly dedented, near "'s escape this'"
at Parser.expect (/Users/cln/src/js-yaml/lib/yaml.js:183:9)
at Parser.parseHash (/Users/cln/src/js-yaml/lib/yaml.js:287:12)
at Parser.parse (/Users/cln/src/js-yaml/lib/yaml.js:244:19)
at Object.exports.eval (/Users/cln/src/js-yaml/lib/yaml.js:388:46)
at /Users/cln/src/js-yaml/examples/run.js:14:20
at FSReqWrap.readFileAfterClose as oncomplete

http://symfony.com/doc/current/components/yaml/yaml_format.html