gistfile1.rb

#!/usr/bin/env ruby

directory = "/Users/omarqureshi/test/"
files = Dir.glob("#{directory}**/*")

out = files.inject({}) do |mem, file|
  mem[directory] ||= []
  remainder = file.gsub(directory, "")
  after_split = remainder.split("/")
  if after_split.size == 1
    mem[directory] << after_split[0] unless File.directory?(directory + after_split[0])
  else
    dirname = directory + after_split[0..-2].join("/")
    mem[dirname] ||= []
    mem[dirname] << after_split[-1] unless File.directory?(dirname + after_split[-1])
  end
  mem
end

puts out.inspect