whitequark/parser — pull request #107 by misfo (2013-09-14 18:38:38+00:00)
Title: Node#equivalent? for testing runtime equivalence

After formatting code, I'd like to be able to check whether I've changed the AST or not. If superfluous parens were removed or added, for instance, the new AST is not `==` to the original, but it's still equivalent. I added a method to check for this kind of equivalence.