State.rb - Ruby Class to deal with the United States of AMERICA!

State.rb

class State
  #usage:
  #State.new.state_by_abbreviation("WY") 
  #=> "Wyoming"
  #State.new.abbreviation_by_state("Wyoming")
  #=> "WY"
  #State.new.abbreviations
  #-Returns all abbreviations
  #State.new.names
  #-Returns all States Names
  #State.new.valid?("WyOmInG")
  #->true
  #State.new.valid?("Hobbiton")
  #->false
  
  def initialize
  end

  def state_by_abbreviation(abbreviation)
    return nil if abbreviation.nil?
    return nil if abbreviation.empty?

    states.fetch(abbreviation.upcase, nil)
  end

  def abbreviation_by_state(state)
    return nil if state.nil?
    return nil if state.empty?

    states.key(state.capitalize)
  end

  def names
    states.values
  end

  def abbreviations
    states.keys
  end

  def valid?(state)
    return false if state.nil?
    return false if state.empty?
    return false if state.length < 2

    if state.length == 2
      state_by_abbreviation(state).nil? ? false : true
    else
      abbreviation_by_state(state).nil? ? false : true
    end
  end

  def states
    {
      'AL' => 'Alabama',
      'AK' => 'Alaska',
      'AS' => 'American Samoa',
      'AZ' => 'Arizona',
      'AR' => 'Arkansas',
      'CA' => 'California',
      'CO' => 'Colorado',
      'CT' => 'Connecticut',
      'DE' => 'Delaware',
      'DC' => 'District of Columbia',
      'FL' => 'Florida',
      'GA' => 'Georgia',
      'GU' => 'Guam',
      'HI' => 'Hawaii',
      'ID' => 'Idaho',
      'IL' => 'Illinois',
      'IN' => 'Indiana',
      'IA' => 'Iowa',
      'KS' => 'Kansas',
      'KY' => 'Kentucky',
      'LA' => 'Louisiana',
      'ME' => 'Maine',
      'MH' => 'Marshall Islands',
      'MD' => 'Maryland',
      'MA' => 'Massachusetts',
      'MI' => 'Michigan',
      'MN' => 'Minnesota',
      'MS' => 'Mississippi',
      'MO' => 'Missouri',
      'MT' => 'Montana',
      'NE' => 'Nebraska',
      'NV' => 'Nevada',
      'NH' => 'New Hampshire',
      'NJ' => 'New Jersey',
      'NM' => 'New Mexico',
      'NY' => 'New York',
      'NC' => 'North Carolina',
      'ND' => 'North Dakota',
      'OH' => 'Ohio',
      'OK' => 'Oklahoma',
      'OR' => 'Oregon',
      'PW' => 'Palau',
      'PA' => 'Pennsylvania',
      'PR' => 'Puerto Rico',
      'RI' => 'Rhode Island',
      'SC' => 'South Carolina',
      'SD' => 'South Dakota',
      'TN' => 'Tennessee',
      'TX' => 'Texas',
      'UT' => 'Utah',
      'VT' => 'Vermont',
      'VI' => 'Virgin Islands',
      'VA' => 'Virginia',
      'WA' => 'Washington',
      'WV' => 'West Virginia',
      'WI' => 'Wisconsin',
      'WY' => 'Wyoming'
    }
  end
end

state_spec.rb

require "spec_helper"

describe State do

  before(:all) do
    @states = State.new
  end

  it "should return only abbreviations" do
    states = @states.abbreviations
    states.should include "AL"
    states.should include "WY"
  end

  it "should return only names of states" do
    states = @states.names
    states.should include "Alabama"
    states.should include "Wyoming"
  end

  it "should return the abbreviation based on the state name" do
    @states.abbreviation_by_state("Wyoming").should eq "WY"
    @states.abbreviation_by_state("wyoming").should eq "WY"
    @states.abbreviation_by_state("WYOMING").should eq "WY"
    @states.abbreviation_by_state("wYoMiNg").should eq "WY"
    @states.abbreviation_by_state("").should eq nil
    @states.abbreviation_by_state(" ").should eq nil
  end

  it "should return the state based on the abbreviation" do
    @states.state_by_abbreviation("WY").should eq "Wyoming"
    @states.state_by_abbreviation("wy").should eq "Wyoming"
    @states.state_by_abbreviation("wY").should eq "Wyoming"
    @states.state_by_abbreviation("Wy").should eq "Wyoming"
    @states.state_by_abbreviation("").should eq nil
    @states.state_by_abbreviation(" ").should eq nil
  end


  it "should return false if valid is passed a state with a nil value" do
    @states.valid?(nil).should eq false
  end

  it "should return false if valid is passed a state with a blank or empty value" do
    @states.valid?("").should eq false
  end

  it "should return false if valid is passed a state with less than 2 characters" do
    @states.valid?("A").should eq false
  end

  it "should return false if abbreviation is not found" do
    @states.valid?("BA").should eq false
  end

  it "should return true if abbreviation is found" do
    @states.valid?("GA").should eq true
  end

  it "should return false if state is not found" do
    @states.valid?("CRAP").should eq false
  end

  it "should return true if state is found" do
    @states.valid?("Maine").should eq true
  end
end