A passing spec for the simple number parser.

number_parser_spec.rb

# -*- coding: utf-8 -*-
require 'spec_helper'


describe Parsers::NumberParser do

  before(:each) do
    @p = Parsers::NumberParser.new
  end

  it 'can be instantiated' do
    @p.should be_instance_of Parsers::NumberParser
  end


  context '#number?' do
    it 'correctly determines that text is a number' do
      @p.number?('fifty-five').should be_true
    end

    it 'correctly determines that text is not a number' do
      @p.number?('53x9').should be_false
    end
  end


  context '#parse' do
    it 'rejects bad input' do
      expect { @p.parse('xxx') }.to raise_error
    end

    it 'can parse a number regardless of case' do
      @p.parse('one').should == 1
      @p.parse('One').should == 1
      @p.parse('ONE').should == 1
    end

    it 'parses a number with a leading space' do
      @p.parse(' thirteen hundred').should == @p.parse('thirteen hundred')
    end
    
    specify { @p.parse('two').should == 2 }
    specify { @p.parse('nine').should == 9 }
    specify { @p.parse('fifteen').should == 15 }
    specify { @p.parse('forty-one').should == 41 }
    specify { @p.parse('one hundred three').should == 103 }
    specify { @p.parse('four hundred').should == 400 }
    specify { @p.parse('four hundred one').should == 401 }
    specify { @p.parse('thirteen hundred one').should == 1301 }
    specify { @p.parse('thirteen hundred thirteen').should == 1313 }
  end

end