TDDBC Tokyo 2013-03 のお題にチャレンジしてみた （お題の参考）https://github.com/sue445/tddbc_tokyo_20130316

LTSV.pm

package LTSV;

use strict;
use warnings;
use feature qw/ say /;

sub new {
    my $pkg = shift;
    bless{
        attributes => {},
    }, $pkg;
}

sub set {
    my ($pkg, $key, $val) = @_;
    $pkg->{attributes}->{$key} = $val;
}

sub get {
    my ($pkg, $key) = @_;
    $pkg->{attributes}->{$key};
}

sub dump {
    my $pkg = shift;

    my $str = '';
    while ( my ($key, $val) = each($pkg->{attributes}) ) {
        $str .= $key . ':' . $val . "\t";
    }
    $str =~ s/\t$//;
    $str . "\n";
}

sub parse {
    my ($class, $str) = @_;

    my $ltsv = $class->new;

    chomp($str);

    my @kvs = split("\t", $str);
    foreach my $kv (@kvs) {
        my ($key, $val) = split(':', $kv, 2);
        $ltsv->set($key, $val);
    }
    $ltsv;
}

1;

ltsv.rb

class LTSV
  def initialize
    @attributes = {}
  end

  def set(key, val)
    raise ArgumentError if key.nil? || key.empty?
    @attributes[key] = val
    self
  end

  def get(key)
    @attributes[key]
  end

  def dump
    @attributes.map{|key, val| "#{key}:#{val}"}.join("\t").tap { |str|
      str.concat("\n") unless str.empty?
    }
  end

  class << self
    def parse(row)
      LTSV.new.tap do |ltsv|
        row.chomp.split("\t").map { |kv|
          key, val = kv.split(':', 2)
          ltsv.set(key, val)
        }
      end
    end
  end
end

LTSV.t

use strict;
use warnings;

use Test::More;

BEGIN { use_ok('LTSV'); }

my $ltsv = LTSV->new;

ok($ltsv->set('foo', 'bar'), 'LTSV provides set method');

is($ltsv->get('foo'), 'bar', 'LTSV provides get method');

$ltsv->set('foo', 'hoge');
is($ltsv->get('foo'), 'hoge', 'LTSV#set overrides key');

$ltsv->set('hoge', 'fuga');
is($ltsv->dump, "foo:hoge\thoge:fuga\n", 'LTSV provides dump method');

{
    my $ltsv = LTSV->parse("foo:hoge\thoge:fuga\n");
    is($ltsv->get('foo'),  'hoge', 'LTSV parses given string');
    is($ltsv->get('hoge'), 'fuga', 'LTSV parses given string');
}

done_testing;

ltsv_test.rb

require 'test/unit'
require File.expand_path('../ltsv', __FILE__)

class TestLTSV < Test::Unit::TestCase
  def setup
    @ltsv = LTSV.new
  end

  def test_set
    assert_nothing_raised ArgumentError do
      @ltsv.set('foo', 'hoge')
    end
  end

  def test_get
    @ltsv.set('foo', 'hoge')
    assert_equal 'hoge', @ltsv.get('foo')
  end

  def test_not_key_get
    @ltsv.set('foo', 'hoge')
    assert_nil @ltsv.get('bar')
  end

  def test_dump
    @ltsv.set('hoge', 'fuga').set('foo', 'bar')
    assert_equal "hoge:fuga\tfoo:bar\n", @ltsv.dump
  end

  def test_override_value
    @ltsv.set('foo', 'bar').set('foo', 'piyo')
    assert_equal 'piyo', @ltsv.get('foo')
  end

  def test_parse
    ltsv = LTSV.parse("foo:hoge\tbar:fuga\n")
    assert_equal 'hoge', ltsv.get('foo')
    assert_equal 'fuga', ltsv.get('bar')
  end

  def test_raise_nil_key
    assert_raise ArgumentError do
      @ltsv.set(nil, 'hey')
    end
  end

  def test_raise_empty_key
    assert_raise ArgumentError do
      @ltsv.set('', 'hey')
    end
  end
end