rubinius/rubinius — pull request #1545 by leocassarani (2012-02-04 03:39:16+00:00)
Title: Make Error#to_yaml produce expected output under 1.9

`Exception#to_yaml_properties` specifically removes the `@backtrace` and `@custom_backtrace` instance variables so as not to pollute the YAML output. However, under 1.9 instance variables are represented as symbols rather than strings, so those two variables were not being removed under 1.9, causing them to appear in the output of `Error#to_yaml`, which in turn made the relevant RubySpec fail.

Separating the implementations of the method under 1.8 and 1.9 fixes the spec.