zone_finder.rb

require 'open-uri'
require 'fastercsv'

class ZoneFinder
  
  # Creates a ZoneFinder object
  def initialize(network_data_path)
    @network_data_path = network_data_path
  end
  
  # Returns the network data parsed from a csv file as an array of 
  # FasterCSV rows.
  def fetch_network_data
    return FasterCSV.parse(
      get_data().gsub('"', '\''),
      :headers => true
    )
  end
  
  def get_data
    open(@network_data_path).read
  end
  
end

zone_finder_spec.rb

require 'zone_finder'

describe ZoneFinder, "#fetch_network_data" do

  before(:each) do
    @network_data_handle = mock('network data handle')
    @network_data_handle.stub!(:read).and_return("data")
    
    @zone_finder = ZoneFinder.new("test-network-data-path")
    @zone_finder.stub!(:open).and_return(@network_data_handle)
  end
  
  it "should attempt to open the file located at the network_data_path" do
    @zone_finder.should_receive(:open).with("test-network-data-path").and_return(@network_data_handle)

    @zone_finder.fetch_network_data
  end
  
  it "should read the data from the network data file" do
    @network_data_handle.should_receive(:read).and_return("data")
    
    @zone_finder.fetch_network_data
  end

  it "should replace double quotes with single quotes in the returned csv document" do
    @zone_finder.stub!(:get_data).and_return('"test-speak-marks"')
    FasterCSV.should_receive(:parse).with("'test-speak-marks'", anything)
    
    @zone_finder.send(:fetch_network_data)
  end
  
  it "should parse the returned csv document and return it" do
    @network_data_handle.stub!(:read).and_return("csv-data")
    FasterCSV.should_receive(:parse).with("csv-data", :headers => true).and_return("csv-data-parsed")
    
    @zone_finder.send(:fetch_network_data).should == "csv-data-parsed"
  end
  
end