elixir-lang/elixir — pull request #2370 by keithseahus (2014-06-01 12:51:14+00:00)
Title: Fix Path.absname("/") and Path.expand("/") to return the absolute path "/".

Since "/" is surely an absolute path and Path.absname("/foo") returns "/foo", programmers will expect that Path.absname("/") should return "/", and the same applies to Path.expand("/").
The past code retruned "" for Path.absname("/") and FunctionClauseError for Path.expand("/").