smart_pluralize.rb

# == a smarter way to pluralize
#
# Accepts an integer as an optional argument
# >> "actress".smart_pluralize
# => "actresses"
# >> "guitar".smart_pluralize(1)
# => "guitar"
# >> "monkey".smart_pluralize(2)
# => "monkeys"
#
# Understands quantity strings
# >> "1 monkey".smart_pluralize
# => "1 monkey"
# >> "900 monkey".smart_pluralize
# => "900 monkeys"
class String
  def smart_pluralize num=self
    num.to_i.abs == 1 ? self : pluralize
  end
end

smart_pluralize_spec.rb

require 'rubygems'
require 'activesupport'
require File.join(File.dirname(__FILE__), 'smart_pluralize')
require 'spec'
 
describe String do
  it "should respond to smart_pluralize" do
    "".respond_to?(:smart_pluralize).should be_true
  end
 
  describe "with one integer argument" do
    it "should not pluralize with arg of 1" do
      "monkey".smart_pluralize(1).should == "monkey"
    end
 
    it "should not pluralize with arg of -1" do
      "monkey".smart_pluralize(-1).should == "monkey"
    end
 
    it "should pluralize with arg of 0" do
      "monkey".smart_pluralize(0).should == "monkeys"
    end
 
    it "should pluralize with arg of 2..100" do
      (2..100).each do |i|
        "monkey".smart_pluralize(i).should == "monkeys"
      end
    end
 
    it "should pluralize with arg of -100..-2" do
      (-100..-2).each do |i|
        "monkey".smart_pluralize(i).should == "monkeys"
      end
    end
  end
 
  describe "with no args" do
    it "should pluralize with no args" do
      "monkey".smart_pluralize.should == "monkeys"
    end
 
    it "should not pluralize 1 monkey" do
      "1 monkey".smart_pluralize.should == "1 monkey"
    end
 
    it "should not pluralize -1 monkey" do
      "-1 monkey".smart_pluralize.should == "-1 monkey"
    end
 
    it "should pluralize 0 monkey" do
      "0 monkey".smart_pluralize.should == "0 monkeys"
    end
 
    it "should pluralize 2 - 100 monkeys" do
      (2..100).each do |i|
        "#{i} monkey".smart_pluralize.should == "#{i} monkeys"
      end
    end
 
    it "should pluralize -100 through -2 monkeys" do
      (-100..-2).each do |i|
        "#{i} monkey".smart_pluralize.should == "#{i} monkeys"
      end
    end
  end
end