rspec/rspec-core — pull request #857 by natsumesou (2013-04-03 17:03:31+00:00)
Title: Using let variable in before(:all) hook, example store let variable in each scope and it break rspec test.

I think this is a bug. and should not store let variable.

this is demo spec.
https://gist.github.com/natsumesou/5300504