tc_zoneinfo_timezone_info.rb

# encoding: UTF-8

require File.join(File.expand_path(File.dirname(__FILE__)), 'test_utils')
require 'tempfile'

include TZInfo

# Use send as a workaround for erroneous 'wrong number of arguments' errors with
# JRuby 9.0.5.0 when calling methods with Java implementations. See #114.
send(:using, RubyCoreSupport::UntaintExt) if RubyCoreSupport.const_defined?(:UntaintExt)

class TCZoneinfoTimezoneInfo < Minitest::Test

  begin
    Time.at(-2147483649)
    Time.at(2147483648)
    SUPPORTS_64BIT = true
  rescue RangeError
    SUPPORTS_64BIT = false
  end

  begin
    Time.at(-1)
    Time.at(-2147483648)
    SUPPORTS_NEGATIVE = true
  rescue ArgumentError
    SUPPORTS_NEGATIVE = false
  end

  def assert_period(abbreviation, utc_offset, std_offset, dst, start_at, end_at, info)    
    if start_at
      period = info.period_for_utc(start_at)
    elsif end_at
      period = info.period_for_utc(TimeOrDateTime.wrap(end_at).add_with_convert(-1).to_orig)
    else
      # no transitions, pick the epoch
      period = info.period_for_utc(Time.utc(1970, 1, 1))
    end
    
    assert_equal(abbreviation, period.abbreviation)
    assert_equal(utc_offset, period.utc_offset)
    assert_equal(std_offset, period.std_offset)
    assert_equal(dst, period.dst?)
    
    if start_at
      refute_nil(period.utc_start_time)
      assert_equal(start_at, period.utc_start_time)
    else
      assert_nil(period.utc_start_time)
    end
    
    if end_at
      refute_nil(period.utc_end_time)
      assert_equal(end_at, period.utc_end_time)
    else
      assert_nil(period.utc_end_time)
    end
  end
  
  def convert_times_to_i(items, key = :at)
    items.each do |item|
      if item[key].kind_of?(Time)
        item[key] = item[key].utc.to_i
      end
    end
  end
  
  def select_with_32bit_values(items, key = :at)
    items.select do |item|
      i = item[key]
      i >= -2147483648 && i <= 2147483647
    end
  end
  
  def pack_int64_network_order(values)
    values.collect {|value| [value >> 32, value & 0xFFFFFFFF]}.flatten.pack('NN' * values.length)
  end
  
  def pack_int64_signed_network_order(values)
    # Convert to the equivalent 64-bit unsigned integer with the same bit representation
    pack_int64_network_order(values.collect {|value| value < 0 ? value + 0x10000000000000000 : value})
  end
  
  def write_tzif(format, offsets, transitions, leaps = [], options = {})
    
    # Options for testing malformed zoneinfo files.
    magic = options[:magic]
    section2_magic = options[:section2_magic]
    abbrev_separator = options[:abbrev_separator] || "\0"
    abbrev_offset_base = options[:abbrev_offset_base] || 0
      
    unless magic
      if format == 1
        magic = "TZif\0"
      elsif format >= 2
        magic = "TZif#{format}"
      else
        raise ArgumentError, 'Invalid format specified'
      end
    end
    
    if section2_magic.kind_of?(Proc)
      section2_magic = section2_magic.call(format)
    else
      section2_magic = magic unless section2_magic
    end
    
    convert_times_to_i(transitions)
    convert_times_to_i(leaps)    
    
    abbrevs = offsets.collect {|o| o[:abbrev]}.uniq
    
    if abbrevs.length > 0
      abbrevs = abbrevs.collect {|a| a.encode('UTF-8')} if abbrevs.first.respond_to?(:encode)    
    
      if abbrevs.first.respond_to?(:bytesize)
        abbrevs_length = abbrevs.inject(0) {|sum, a| sum + a.bytesize + abbrev_separator.bytesize}
      else
        abbrevs_length = abbrevs.inject(0) {|sum, a| sum + a.length + abbrev_separator.length}
      end
    else
      abbrevs_length = 0
    end
  
    b32_transitions = select_with_32bit_values(transitions)    
    b32_leaps = select_with_32bit_values(leaps)
  
    Tempfile.open('tzinfo-test-zone') do |file|
      file.binmode
      
      file.write(
        [magic, offsets.length, offsets.length, leaps.length, 
         b32_transitions.length, offsets.length, abbrevs_length].pack('a5 x15 NNNNNN'))
	
      unless b32_transitions.empty?
        file.write(b32_transitions.collect {|t| t[:at]}.pack('N' * b32_transitions.length))
        file.write(b32_transitions.collect {|t| t[:offset_index]}.pack('C' * b32_transitions.length))
      end
      
      offsets.each do |offset|
        index = abbrevs.index(offset[:abbrev])
        abbrev_offset = abbrev_offset_base
        0.upto(index - 1) {|i| abbrev_offset += abbrevs[i].length + 1}
      
        file.write([offset[:gmtoff], offset[:isdst] ? 1 : 0, abbrev_offset].pack('NCC'))
      end
          
      abbrevs.each do |a|
        file.write(a)
        file.write(abbrev_separator)
      end
      
      b32_leaps.each do |leap|
        file.write([leap[:at], leap[:seconds]].pack('NN'))
      end
      
      unless offsets.empty?
        file.write("\0" * offsets.length * 2)
      end
      
      if format >= 2
        file.write(
          [section2_magic, offsets.length, offsets.length, leaps.length, 
           transitions.length, offsets.length, abbrevs_length].pack('a5 x15 NNNNNN'))
    
        unless transitions.empty?
          file.write(pack_int64_signed_network_order(transitions.collect {|t| t[:at]}))
          file.write(transitions.collect {|t| t[:offset_index]}.pack('C' * transitions.length))
        end
        
        offsets.each do |offset|
          index = abbrevs.index(offset[:abbrev])
          abbrev_offset = abbrev_offset_base
          0.upto(index - 1) {|i| abbrev_offset += abbrevs[i].length + 1}
        
          file.write([offset[:gmtoff], offset[:isdst] ? 1 : 0, abbrev_offset].pack('NCC'))
        end
        
        abbrevs.each do |a|
          file.write(a)
          file.write(abbrev_separator)
        end
        
        leaps.each do |leap|          
          file.write(pack_int64_signed_network_order([leap[:at]]))
          file.write([leap[:seconds]].pack('N'))
        end
        
        unless offsets.empty?
          file.write("\0" * offsets.length * 2)
        end
        
        # Empty POSIX timezone string
        file.write("\n\n")
      end
      
      file.flush
      
      yield file.path, format
    end
  end
  
  def tzif_test(offsets, transitions, leaps = [], options = {}, &block)
    min_format = options[:min_format] || 1
    
    min_format.upto(3) do |format|
      write_tzif(format, offsets, transitions, leaps, options, &block)
    end
  end
  
  def test_load
    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST'},
      {:gmtoff => 7200, :isdst => true,  :abbrev => 'XDT'},
      {:gmtoff =>    0, :isdst => false, :abbrev => 'XNST'}]
      
    transitions = [
      {:at => Time.utc(1971,  1,  2), :offset_index => 1},
      {:at => Time.utc(1980,  4, 22), :offset_index => 2},
      {:at => Time.utc(1980, 10, 21), :offset_index => 1},
      {:at => Time.utc(2000, 12, 31), :offset_index => 3}]
  
    tzif_test(offsets, transitions) do |path, format|     
      info = ZoneinfoTimezoneInfo.new('Zone/One', path)
      assert_equal('Zone/One', info.identifier)
      
      assert_period(:LMT,  3542,    0, false,                    nil, Time.utc(1971,  1,  2), info)
      assert_period(:XST,  3600,    0, false, Time.utc(1971,  1,  2), Time.utc(1980,  4, 22), info)
      assert_period(:XDT,  3600, 3600,  true, Time.utc(1980,  4, 22), Time.utc(1980, 10, 21), info)
      assert_period(:XST,  3600,    0, false, Time.utc(1980, 10, 21), Time.utc(2000, 12, 31), info)
      assert_period(:XNST,    0,    0, false, Time.utc(2000, 12, 31),                    nil, info)
    end
  end
  
  def test_load_negative_utc_offset
    offsets = [
      {:gmtoff => -12492, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => -12000, :isdst => false, :abbrev => 'XST'},
      {:gmtoff => -8400,  :isdst => true,  :abbrev => 'XDT'},
      {:gmtoff => -8400,  :isdst => false, :abbrev => 'XNST'}]
      
    transitions = [
      {:at => Time.utc(1971,  7,  9, 3,  0, 0), :offset_index => 1},
      {:at => Time.utc(1972, 10, 12, 3,  0, 0), :offset_index => 2},
      {:at => Time.utc(1973,  4, 29, 3,  0, 0), :offset_index => 1},
      {:at => Time.utc(1992,  4,  1, 4, 30, 0), :offset_index => 3}]
  
    tzif_test(offsets, transitions) do |path, format|     
      info = ZoneinfoTimezoneInfo.new('Zone/One', path)
      assert_equal('Zone/One', info.identifier)
      
      assert_period(:LMT, -12492,    0, false,                              nil, Time.utc(1971,  7,  9, 3,  0, 0), info)
      assert_period(:XST, -12000,    0, false, Time.utc(1971,  7,  9, 3,  0, 0), Time.utc(1972, 10, 12, 3,  0, 0), info)
      assert_period(:XDT, -12000, 3600,  true, Time.utc(1972, 10, 12, 3,  0, 0), Time.utc(1973,  4, 29, 3,  0, 0), info)
      assert_period(:XST, -12000,    0, false, Time.utc(1973,  4, 29, 3,  0, 0), Time.utc(1992,  4,  1, 4, 30, 0), info)
      assert_period(:XNST, -8400,    0, false, Time.utc(1992,  4,  1, 4, 30, 0),                              nil, info)
    end
  end
  
  def test_load_dst_first
    offsets = [
      {:gmtoff => 7200, :isdst => true,  :abbrev => 'XDT'},
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST'},
      {:gmtoff =>    0, :isdst => false, :abbrev => 'XNST'}]
      
    transitions = [
      {:at => Time.utc(1979,  1,  2), :offset_index => 2},
      {:at => Time.utc(1980,  4, 22), :offset_index => 0},
      {:at => Time.utc(1980, 10, 21), :offset_index => 2},
      {:at => Time.utc(2000, 12, 31), :offset_index => 3}]
  
    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/Two', path)
      assert_equal('Zone/Two', info.identifier)
      
      assert_period(:LMT, 3542, 0, false, nil, Time.utc(1979, 1, 2), info)      
    end
  end
    
  def test_load_no_transitions
    offsets = [{:gmtoff => -12094, :isdst => false, :abbrev => 'LT'}]
        
    tzif_test(offsets, []) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/three', path)
      assert_equal('Zone/three', info.identifier)
      
      assert_period(:LT, -12094, 0, false, nil, nil, info)
    end
  end
  
  def test_load_no_offsets
    offsets = []
    transitions = [{:at => Time.utc(2000, 12, 31), :offset_index => 0}]

    tzif_test(offsets, transitions) do |path, format|
      assert_raises(InvalidZoneinfoFile) do
        ZoneinfoTimezoneInfo.new('Zone', path)
      end
    end
  end

  def test_load_invalid_offset_index
    offsets = [{:gmtoff => -0, :isdst => false, :abbrev => 'LMT'}]
    transitions = [{:at => Time.utc(2000, 12, 31), :offset_index => 2}]
        
    tzif_test(offsets, transitions) do |path, format|
      assert_raises(InvalidZoneinfoFile) do
        ZoneinfoTimezoneInfo.new('Zone', path)
      end
    end
  end
  
  def test_load_with_leap_seconds
    offsets = [{:gmtoff => -0, :isdst => false, :abbrev => 'LMT'}]
    leaps = [{:at => Time.utc(1972,6,30,23,59,60), :seconds => 1}]
        
    tzif_test(offsets, [], leaps) do |path, format|
      assert_raises(InvalidZoneinfoFile) do
        ZoneinfoTimezoneInfo.new('Zone', path)
      end
    end
  end
  
  def test_load_invalid_magic
    ['TZif4', 'tzif2', '12345'].each do |magic|    
      offsets = [{:gmtoff => -12094, :isdst => false, :abbrev => 'LT'}]
          
      tzif_test(offsets, [], [], :magic => magic) do |path, format|        
        assert_raises(InvalidZoneinfoFile) do
          ZoneinfoTimezoneInfo.new('Zone2', path)
        end
      end
    end
  end
  
  # These tests can only be run if the platform supports 64-bit Times. When
  # 64-bit support is unavailable, the second section will not be read, so no 
  # error will be raised.
  if SUPPORTS_64BIT
    def test_load_invalid_section2_magic
      ['TZif4', 'tzif2', '12345'].each do |section2_magic|    
        offsets = [{:gmtoff => -12094, :isdst => false, :abbrev => 'LT'}]
            
        tzif_test(offsets, [], [], :min_format => 2, :section2_magic => section2_magic) do |path, format|        
          assert_raises(InvalidZoneinfoFile) do
            ZoneinfoTimezoneInfo.new('Zone4', path)
          end
        end
      end
    end
    
    def test_load_mismatched_section2_magic
      minus_one = Proc.new {|f| f == 2 ? "TZif\0" : "TZif#{f - 1}" }
      plus_one = Proc.new {|f| "TZif#{f + 1}" }
      
      [minus_one, plus_one].each do |section2_magic|    
        offsets = [{:gmtoff => -12094, :isdst => false, :abbrev => 'LT'}]
            
        tzif_test(offsets, [], [], :min_format => 2, :section2_magic => section2_magic) do |path, format|        
          assert_raises(InvalidZoneinfoFile) do
            ZoneinfoTimezoneInfo.new('Zone5', path)
          end
        end
      end
    end
  end
  
  def test_load_invalid_format
    Tempfile.open('tzinfo-test-zone') do |file|
      file.write('Invalid')
      file.flush
      
      assert_raises(InvalidZoneinfoFile) do
        ZoneinfoTimezoneInfo.new('Zone3', file.path)
      end
    end
  end
  
  def test_load_missing_abbrev_null_termination
    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false,  :abbrev => 'XST'}]
      
    transitions = [
      {:at => Time.utc(2000, 1, 1), :offset_index => 1}]
            
    tzif_test(offsets, transitions, [], :abbrev_separator => '^') do |path, format|
      assert_raises(InvalidZoneinfoFile) do
        ZoneinfoTimezoneInfo.new('Zone', path)
      end
    end
  end
  
  def test_load_out_of_range_abbrev_offsets
    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false,  :abbrev => 'XST'}]
      
    transitions = [
      {:at => Time.utc(2000, 1, 1), :offset_index => 1}]
            
    tzif_test(offsets, transitions, [], :abbrev_offset_base => 8) do |path, format|
      assert_raises(InvalidZoneinfoFile) do
        ZoneinfoTimezoneInfo.new('Zone', path)
      end
    end
  end
  
  def test_load_before_epoch
    # Some platforms don't support negative timestamps for times before the
    # epoch. Check that they are returned when supported and skipped when not.

    # Note the last transition before the epoch (and within the 32-bit range) is
    # moved to the epoch on platforms that do not support negative timestamps.
  
    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST'},
      {:gmtoff => 7200, :isdst => true,  :abbrev => 'XDT'},
      {:gmtoff =>    0, :isdst => false, :abbrev => 'XNST'}]
      
    transitions = [
      {:at =>             -694224000, :offset_index => 1}, # Time.utc(1948,  1,  2)
      {:at =>              -21945600, :offset_index => 2}, # Time.utc(1969,  4, 22)
      {:at => Time.utc(1970, 10, 21), :offset_index => 1},
      {:at => Time.utc(2000, 12, 31), :offset_index => 3}]
  
    tzif_test(offsets, transitions) do |path, format|     
      info = ZoneinfoTimezoneInfo.new('Zone/Negative', path)
      assert_equal('Zone/Negative', info.identifier)
      
      if SUPPORTS_NEGATIVE
        assert_period(:LMT,  3542,    0, false,                    nil, Time.utc(1948,  1,  2), info)
        assert_period(:XST,  3600,    0, false, Time.utc(1948,  1,  2), Time.utc(1969,  4, 22), info)
        assert_period(:XDT,  3600, 3600,  true, Time.utc(1969,  4, 22), Time.utc(1970, 10, 21), info)
      else
        assert_period(:LMT,  3542,    0, false,                    nil, Time.utc(1970,  1,  1), info)
        assert_period(:XDT,  3600, 3600,  true, Time.utc(1970,  1,  1), Time.utc(1970, 10, 21), info)
      end
      
      assert_period(:XST,  3600,    0, false, Time.utc(1970, 10, 21), Time.utc(2000, 12, 31), info)
      assert_period(:XNST,    0,    0, false, Time.utc(2000, 12, 31),                    nil, info)
    end
  end

  def test_load_on_epoch
    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST'},
      {:gmtoff => 7200, :isdst => true,  :abbrev => 'XDT'},
      {:gmtoff =>    0, :isdst => false, :abbrev => 'XNST'}]

    transitions = [
      {:at =>             -694224000, :offset_index => 1}, # Time.utc(1948,  1,  2)
      {:at =>              -21945600, :offset_index => 2}, # Time.utc(1969,  4, 22)
      {:at => Time.utc(1970,  1,  1), :offset_index => 1},
      {:at => Time.utc(2000, 12, 31), :offset_index => 3}]

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/Negative', path)
      assert_equal('Zone/Negative', info.identifier)

      if SUPPORTS_NEGATIVE
        assert_period(:LMT,  3542,    0, false,                    nil, Time.utc(1948,  1,  2), info)
        assert_period(:XST,  3600,    0, false, Time.utc(1948,  1,  2), Time.utc(1969,  4, 22), info)
        assert_period(:XDT,  3600, 3600,  true, Time.utc(1969,  4, 22), Time.utc(1970,  1,  1), info)
      else
        assert_period(:LMT,  3542,    0, false,                    nil, Time.utc(1970,  1,  1), info)
      end

      assert_period(:XST,  3600,    0, false, Time.utc(1970,  1,  1), Time.utc(2000, 12, 31), info)
      assert_period(:XNST,    0,    0, false, Time.utc(2000, 12, 31),                    nil, info)
    end
  end

  def test_load_64bit
    # Some platforms support 64-bit Times, others only 32-bit. The TZif version
    # 2 and later format contains both 32-bit and 64-bit times.
    
    # Where 64-bit is supported and a TZif 2 or later file is provided, the 
    # 64-bit times should be used, otherwise the 32-bit information should be 
    # used.
  
    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST'},
      {:gmtoff => 7200, :isdst => true,  :abbrev => 'XDT'},
      {:gmtoff =>    0, :isdst => false, :abbrev => 'XNST'}]
      
    transitions = [
      {:at =>            -3786739200, :offset_index => 1}, # Time.utc(1850,  1,  2)
      {:at => Time.utc(2003,  4, 22), :offset_index => 2},
      {:at => Time.utc(2003, 10, 21), :offset_index => 1},
      {:at =>             2240524800, :offset_index => 3}] # Time.utc(2040, 12, 31)
  
    tzif_test(offsets, transitions) do |path, format|     
      info = ZoneinfoTimezoneInfo.new('Zone/SixtyFour', path)
      assert_equal('Zone/SixtyFour', info.identifier)
  
      if SUPPORTS_64BIT && format >= 2
        assert_period(:LMT,  3542,    0, false,                    nil, Time.utc(1850,  1,  2), info)
        assert_period(:XST,  3600,    0, false, Time.utc(1850,  1,  2), Time.utc(2003,  4, 22), info)
        assert_period(:XDT,  3600, 3600,  true, Time.utc(2003,  4, 22), Time.utc(2003, 10, 21), info)
        assert_period(:XST,  3600,    0, false, Time.utc(2003, 10, 21), Time.utc(2040, 12, 31), info)
        assert_period(:XNST,    0,    0, false, Time.utc(2040, 12, 31),                    nil, info)
      else
        assert_period(:LMT,  3542,    0, false,                    nil, Time.utc(2003,  4, 22), info)
        assert_period(:XDT,  3600, 3600,  true, Time.utc(2003,  4, 22), Time.utc(2003, 10, 21), info)
        assert_period(:XST,  3600,    0, false, Time.utc(2003, 10, 21),                    nil, info)
      end
    end
  end
  
  def test_load_64bit_range
    # The full range of 64 bit timestamps is not currently supported because of
    # the way transitions are indexed. Transitions outside the supported range
    # will be ignored.

    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST'},
      {:gmtoff => 7200, :isdst => false, :abbrev => 'XNST'}]

    transitions = [
      {:at => -2**63,                :offset_index => 1},
      {:at => Time.utc(2014, 5, 27), :offset_index => 2},
      {:at => 2**63 - 1,             :offset_index => 0}]

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/SixtyFourRange', path)
      assert_equal('Zone/SixtyFourRange', info.identifier)

      if SUPPORTS_64BIT && format >= 2
        # When the full range is supported, the following periods will be defined:
        #assert_period(:LMT,  3542, 0, false, nil,                    Time.at(-2**63).utc,    info)
        #assert_period(:XST,  3600, 0, false, Time.at(-2**63).utc,    Time.utc(2014, 5, 27),  info)
        #assert_period(:XNST, 7200, 0, false, Time.utc(2014, 5, 27),  Time.at(2**63 - 1).utc, info)
        #assert_period(:LMT,  3542, 0, false, Time.at(2**63 - 1).utc, nil,                    info)

        # Without full range support, the following periods will be defined:
        assert_period(:LMT,  3542, 0, false, nil,                   Time.utc(2014, 5, 27), info)
        assert_period(:XNST, 7200, 0, false, Time.utc(2014, 5, 27), nil,                   info)
      else
        assert_period(:LMT,  3542, 0, false, nil,                   Time.utc(2014, 5, 27), info)
        assert_period(:XNST, 7200, 0, false, Time.utc(2014, 5, 27), nil,                   info)
      end
    end
  end

  def test_load_supported_64bit_range
    # The full range of 64 bit timestamps is not currently supported because of
    # the way transitions are indexed. Transitions outside the supported range
    # will be ignored.

    min_timestamp = -8520336000 # Time.utc(1700, 1, 1).to_i
    max_timestamp = 16725225600 # Time.utc(2500, 1, 1).to_i

    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST'},
      {:gmtoff => 7200, :isdst => false, :abbrev => 'XNST'}]

    transitions = [
      {:at => min_timestamp,         :offset_index => 1},
      {:at => Time.utc(2014, 5, 27), :offset_index => 2},
      {:at => max_timestamp - 1,     :offset_index => 0}]

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/SupportedSixtyFourRange', path)
      assert_equal('Zone/SupportedSixtyFourRange', info.identifier)

      if SUPPORTS_64BIT && format >= 2
        assert_period(:LMT,  3542, 0, false, nil,                            Time.at(min_timestamp).utc,     info)
        assert_period(:XST,  3600, 0, false, Time.at(min_timestamp).utc,     Time.utc(2014, 5, 27),          info)
        assert_period(:XNST, 7200, 0, false, Time.utc(2014, 5, 27),          Time.at(max_timestamp - 1).utc, info)
        assert_period(:LMT,  3542, 0, false, Time.at(max_timestamp - 1).utc, nil,                            info)
      else
        assert_period(:LMT,  3542, 0, false, nil,                   Time.utc(2014, 5, 27), info)
        assert_period(:XNST, 7200, 0, false, Time.utc(2014, 5, 27), nil,                   info)
      end
    end
  end

  def test_load_32bit_range
    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST'},
      {:gmtoff => 7200, :isdst => false, :abbrev => 'XNST'}]

    transitions = [
      {:at => -2**31,                :offset_index => 1},
      {:at => Time.utc(2014, 5, 27), :offset_index => 2},
      {:at => 2**31 - 1,             :offset_index => 0}]

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/ThirtyTwoRange', path)
      assert_equal('Zone/ThirtyTwoRange', info.identifier)

      if SUPPORTS_NEGATIVE
        assert_period(:LMT,  3542, 0, false, nil,                    Time.at(-2**31).utc,    info)
        assert_period(:XST,  3600, 0, false, Time.at(-2**31).utc,    Time.utc(2014, 5, 27),  info)
        assert_period(:XNST, 7200, 0, false, Time.utc(2014, 5, 27),  Time.at(2**31 - 1).utc, info)
        assert_period(:LMT,  3542, 0, false, Time.at(2**31 - 1).utc, nil,                    info)
      else
        assert_period(:XST,  3600, 0, false, Time.utc(1970, 1, 1),   Time.utc(2014, 5, 27),  info)
        assert_period(:XNST, 7200, 0, false, Time.utc(2014, 5, 27),  Time.at(2**31 - 1).utc, info)
        assert_period(:LMT,  3542, 0, false, Time.at(2**31 - 1).utc, nil,                    info)
      end
    end
  end

  def test_load_std_offset_changes
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.
  
    offsets = [
      {:gmtoff =>  3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff =>  3600, :isdst => false, :abbrev => 'XST'},
      {:gmtoff =>  7200, :isdst => true,  :abbrev => 'XDT'},
      {:gmtoff => 10800, :isdst => true,  :abbrev => 'XDDT'}]
      
    transitions = [
      {:at => Time.utc(2000, 1, 1), :offset_index => 1},
      {:at => Time.utc(2000, 2, 1), :offset_index => 2},
      {:at => Time.utc(2000, 3, 1), :offset_index => 3},
      {:at => Time.utc(2000, 4, 1), :offset_index => 1}]
  
    tzif_test(offsets, transitions) do |path, format|     
      info = ZoneinfoTimezoneInfo.new('Zone/DoubleDaylight', path)
      assert_equal('Zone/DoubleDaylight', info.identifier)
  
      assert_period(:LMT,  3542,    0, false,                  nil, Time.utc(2000, 1, 1), info)
      assert_period(:XST,  3600,    0, false, Time.utc(2000, 1, 1), Time.utc(2000, 2, 1), info)
      assert_period(:XDT,  3600, 3600,  true, Time.utc(2000, 2, 1), Time.utc(2000, 3, 1), info)
      assert_period(:XDDT, 3600, 7200,  true, Time.utc(2000, 3, 1), Time.utc(2000, 4, 1), info)
      assert_period(:XST,  3600,    0, false, Time.utc(2000, 4, 1), nil, info)
    end
  end
  
  def test_load_std_offset_changes_jump_to_double_dst
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.
  
    offsets = [
      {:gmtoff =>  3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff =>  3600, :isdst => false, :abbrev => 'XST'},      
      {:gmtoff => 10800, :isdst => true,  :abbrev => 'XDDT'}]
      
    transitions = [
      {:at => Time.utc(2000, 4, 1), :offset_index => 1},
      {:at => Time.utc(2000, 5, 1), :offset_index => 2},
      {:at => Time.utc(2000, 6, 1), :offset_index => 1}]
  
    tzif_test(offsets, transitions) do |path, format|     
      info = ZoneinfoTimezoneInfo.new('Zone/DoubleDaylight', path)
      assert_equal('Zone/DoubleDaylight', info.identifier)
  
      assert_period(:LMT,  3542,    0, false,                  nil, Time.utc(2000, 4, 1), info)
      assert_period(:XST,  3600,    0, false, Time.utc(2000, 4, 1), Time.utc(2000, 5, 1), info)
      assert_period(:XDDT, 3600, 7200,  true, Time.utc(2000, 5, 1), Time.utc(2000, 6, 1), info)
      assert_period(:XST,  3600,    0, false, Time.utc(2000, 6, 1),                  nil, info)
    end
  end
  
  def test_load_std_offset_changes_negative
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.
  
    offsets = [
      {:gmtoff => -10821, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => -10800, :isdst => false, :abbrev => 'XST'},
      {:gmtoff =>  -7200, :isdst => true,  :abbrev => 'XDT'},
      {:gmtoff =>  -3600, :isdst => true,  :abbrev => 'XDDT'}]
      
    transitions = [
      {:at => Time.utc(2000, 1, 1), :offset_index => 1},
      {:at => Time.utc(2000, 2, 1), :offset_index => 2},
      {:at => Time.utc(2000, 3, 1), :offset_index => 3},
      {:at => Time.utc(2000, 4, 1), :offset_index => 1},
      {:at => Time.utc(2000, 5, 1), :offset_index => 3},
      {:at => Time.utc(2000, 6, 1), :offset_index => 1}]
  
    tzif_test(offsets, transitions) do |path, format|     
      info = ZoneinfoTimezoneInfo.new('Zone/DoubleDaylight', path)
      assert_equal('Zone/DoubleDaylight', info.identifier)
  
      assert_period(:LMT,  -10821,    0, false,                  nil, Time.utc(2000, 1, 1), info)
      assert_period(:XST,  -10800,    0, false, Time.utc(2000, 1, 1), Time.utc(2000, 2, 1), info)
      assert_period(:XDT,  -10800, 3600,  true, Time.utc(2000, 2, 1), Time.utc(2000, 3, 1), info)
      assert_period(:XDDT, -10800, 7200,  true, Time.utc(2000, 3, 1), Time.utc(2000, 4, 1), info)
      assert_period(:XST,  -10800,    0, false, Time.utc(2000, 4, 1), Time.utc(2000, 5, 1), info)
      assert_period(:XDDT, -10800, 7200,  true, Time.utc(2000, 5, 1), Time.utc(2000, 6, 1), info)
      assert_period(:XST,  -10800,    0, false, Time.utc(2000, 6, 1),                  nil, info)
    end
  end
  
  def test_load_starts_two_hour_std_offset
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.
  
    offsets = [
      {:gmtoff =>  3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff =>  3600, :isdst => false, :abbrev => 'XST'},
      {:gmtoff =>  7200, :isdst => true,  :abbrev => 'XDT'},
      {:gmtoff => 10800, :isdst => true,  :abbrev => 'XDDT'}]
      
    transitions = [
      {:at => Time.utc(2000, 1, 1), :offset_index => 3},
      {:at => Time.utc(2000, 2, 1), :offset_index => 2},
      {:at => Time.utc(2000, 3, 1), :offset_index => 1}]
  
    tzif_test(offsets, transitions) do |path, format|     
      info = ZoneinfoTimezoneInfo.new('Zone/DoubleDaylight', path)
      assert_equal('Zone/DoubleDaylight', info.identifier)
  
      assert_period(:LMT,  3542,    0, false,                  nil, Time.utc(2000, 1, 1), info)
      assert_period(:XDDT, 3600, 7200,  true, Time.utc(2000, 1, 1), Time.utc(2000, 2, 1), info)
      assert_period(:XDT,  3600, 3600,  true, Time.utc(2000, 2, 1), Time.utc(2000, 3, 1), info)
      assert_period(:XST,  3600,    0, false, Time.utc(2000, 3, 1),                  nil, info)
    end
  end
    
  def test_load_starts_only_dst_transition_with_lmt
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 7200, :isdst => true,  :abbrev => 'XDT'}]

    transitions = [{:at => Time.utc(2000, 1, 1), :offset_index => 1}]

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/OnlyDST', path)
      assert_equal('Zone/OnlyDST', info.identifier)

      assert_period(:LMT, 3542,    0, false,                  nil, Time.utc(2000, 1, 1), info)
      assert_period(:XDT, 3542, 3658,  true, Time.utc(2000, 1, 1),                  nil, info)
    end
  end

  def test_load_starts_only_dst_transition_without_lmt
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [{:gmtoff => 7200, :isdst => true,  :abbrev => 'XDT'}]

    transitions = [{:at => Time.utc(2000, 1, 1), :offset_index => 0}]

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/OnlyDST', path)
      assert_equal('Zone/OnlyDST', info.identifier)

      assert_period(:XDT, 3600, 3600, true,                  nil, Time.utc(2000, 1, 1), info)
      assert_period(:XDT, 3600, 3600, true, Time.utc(2000, 1, 1),                  nil, info)
    end
  end
  
  def test_load_switch_to_dst_and_change_utc_offset
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.
  
    # Switch from non-DST to DST at the same time as moving the UTC offset
    # back an hour (i.e. wall clock time doesn't change).
  
    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'YST'},
      {:gmtoff => 3600, :isdst => true,  :abbrev => 'XDT'}]
      
    transitions = [
      {:at => Time.utc(2000, 1, 1), :offset_index => 1},
      {:at => Time.utc(2000, 2, 1), :offset_index => 2}]
  
    tzif_test(offsets, transitions) do |path, format|     
      info = ZoneinfoTimezoneInfo.new('Zone/DoubleDaylight', path)
      assert_equal('Zone/DoubleDaylight', info.identifier)
  
      assert_period(:LMT,  3542,    0, false,                  nil, Time.utc(2000, 1, 1), info)
      assert_period(:YST,  3600,    0, false, Time.utc(2000, 1, 1), Time.utc(2000, 2, 1), info)
      assert_period(:XDT,     0, 3600,  true, Time.utc(2000, 2, 1), nil, info)
    end
  end

  def test_load_apia_international_dateline_change
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    # Pacific/Apia moved across the International Date Line whilst observing
    # daylight savings time.

    offsets = [
      {:gmtoff =>  45184, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => -39600, :isdst => false, :abbrev => '-11'},
      {:gmtoff => -36000, :isdst => true,  :abbrev => '-10'},
      {:gmtoff =>  50400, :isdst => true,  :abbrev => '+14'},
      {:gmtoff =>  46800, :isdst => false, :abbrev => '+13'}]

    transitions = [
      {:at => Time.utc(2011,  4,  2, 14, 0, 0), :offset_index => 1},
      {:at => Time.utc(2011,  9, 24, 14, 0, 0), :offset_index => 2},
      {:at => Time.utc(2011, 12, 30, 10, 0, 0), :offset_index => 3},
      {:at => Time.utc(2012,  3, 31, 14, 0, 0), :offset_index => 4}]

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Test/Pacific/Apia', path)
      assert_equal('Test/Pacific/Apia', info.identifier)

      assert_period(  :LMT,  45184,    0, false,                              nil, Time.utc(2011,  4,  2, 14, 0, 0), info)
      assert_period(:'-11', -39600,    0, false, Time.utc(2011,  4,  2, 14, 0, 0), Time.utc(2011,  9, 24, 14, 0, 0), info)
      assert_period(:'-10', -39600, 3600,  true, Time.utc(2011,  9, 24, 14, 0, 0), Time.utc(2011, 12, 30, 10, 0, 0), info)
      assert_period(:'+14',  46800, 3600,  true, Time.utc(2011, 12, 30, 10, 0, 0), Time.utc(2012,  3, 31, 14, 0, 0), info)
      assert_period(:'+13',  46800,    0, false, Time.utc(2012,  3, 31, 14, 0, 0),                              nil, info)
    end
  end

  def test_load_offset_split_for_different_utc_offset
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [
      {:gmtoff =>  3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff =>  3600, :isdst => false, :abbrev => 'XST1'},
      {:gmtoff =>  7200, :isdst => false, :abbrev => 'XST2'},
      {:gmtoff => 10800, :isdst => true,  :abbrev => 'XDT'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 1},
      {:at => Time.utc(2000,  2, 1), :offset_index => 3},
      {:at => Time.utc(2000,  3, 1), :offset_index => 1},
      {:at => Time.utc(2000,  4, 1), :offset_index => 2},
      {:at => Time.utc(2000,  5, 1), :offset_index => 3},
      {:at => Time.utc(2000,  6, 1), :offset_index => 2},
      {:at => Time.utc(2000,  7, 1), :offset_index => 1},
      {:at => Time.utc(2000,  8, 1), :offset_index => 3},
      {:at => Time.utc(2000,  9, 1), :offset_index => 1},
      {:at => Time.utc(2000, 10, 1), :offset_index => 2},
      {:at => Time.utc(2000, 11, 1), :offset_index => 3},
      {:at => Time.utc(2000, 12, 1), :offset_index => 2}]

    # XDT will be split and defined according to its surrounding standard time
    # offsets.

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/SplitUtcOffset', path)
      assert_equal('Zone/SplitUtcOffset', info.identifier)

      assert_period( :LMT, 3542,    0, false,                   nil, Time.utc(2000,  1, 1), info)
      assert_period(:XST1, 3600,    0, false, Time.utc(2000,  1, 1), Time.utc(2000,  2, 1), info)
      assert_period( :XDT, 3600, 7200,  true, Time.utc(2000,  2, 1), Time.utc(2000,  3, 1), info)
      assert_period(:XST1, 3600,    0, false, Time.utc(2000,  3, 1), Time.utc(2000,  4, 1), info)
      assert_period(:XST2, 7200,    0, false, Time.utc(2000,  4, 1), Time.utc(2000,  5, 1), info)
      assert_period( :XDT, 7200, 3600,  true, Time.utc(2000,  5, 1), Time.utc(2000,  6, 1), info)
      assert_period(:XST2, 7200,    0, false, Time.utc(2000,  6, 1), Time.utc(2000,  7, 1), info)
      assert_period(:XST1, 3600,    0, false, Time.utc(2000,  7, 1), Time.utc(2000,  8, 1), info)
      assert_period( :XDT, 3600, 7200,  true, Time.utc(2000,  8, 1), Time.utc(2000,  9, 1), info)
      assert_period(:XST1, 3600,    0, false, Time.utc(2000,  9, 1), Time.utc(2000, 10, 1), info)
      assert_period(:XST2, 7200,    0, false, Time.utc(2000, 10, 1), Time.utc(2000, 11, 1), info)
      assert_period( :XDT, 7200, 3600,  true, Time.utc(2000, 11, 1), Time.utc(2000, 12, 1), info)
      assert_period(:XST2, 7200,    0, false, Time.utc(2000, 12, 1),                   nil, info)

      1.upto(6) do |i|
        assert_same(info.period_for_utc(Time.utc(2000, i, 1)).offset, info.period_for_utc(Time.utc(2000, i + 6, 1)).offset)
      end
    end
  end

  def test_load_offset_utc_offset_taken_from_minimum_difference_minimum_after
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [
      {:gmtoff =>  3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff =>  3600, :isdst => false, :abbrev => 'XST1'},
      {:gmtoff =>  7200, :isdst => false, :abbrev => 'XST2'},
      {:gmtoff => 10800, :isdst => true,  :abbrev => 'XDT'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 1},
      {:at => Time.utc(2000,  2, 1), :offset_index => 3},
      {:at => Time.utc(2000,  3, 1), :offset_index => 2}]

    # XDT should use the closest utc_offset (7200) (and not an equivalent
    # utc_offset of 3600 and std_offset of 7200).

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/MinimumUtcOffset', path)
      assert_equal('Zone/MinimumUtcOffset', info.identifier)

      assert_period( :LMT, 3542,    0, false,                   nil, Time.utc(2000,  1, 1), info)
      assert_period(:XST1, 3600,    0, false, Time.utc(2000,  1, 1), Time.utc(2000,  2, 1), info)
      assert_period( :XDT, 7200, 3600,  true, Time.utc(2000,  2, 1), Time.utc(2000,  3, 1), info)
      assert_period(:XST2, 7200,    0, false, Time.utc(2000,  3, 1),                   nil, info)
    end
  end

  def test_load_offset_utc_offset_taken_from_minimum_difference_minimum_before
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [
      {:gmtoff =>  3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff =>  3600, :isdst => false, :abbrev => 'XST1'},
      {:gmtoff =>  7200, :isdst => false, :abbrev => 'XST2'},
      {:gmtoff => 10800, :isdst => true,  :abbrev => 'XDT'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 2},
      {:at => Time.utc(2000,  2, 1), :offset_index => 3},
      {:at => Time.utc(2000,  3, 1), :offset_index => 1}]

    # XDT should use the closest utc_offset (7200) (and not an equivalent
    # utc_offset of 3600 and std_offset of 7200).

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/MinimumUtcOffset', path)
      assert_equal('Zone/MinimumUtcOffset', info.identifier)

      assert_period( :LMT, 3542,    0, false,                   nil, Time.utc(2000,  1, 1), info)
      assert_period(:XST2, 7200,    0, false, Time.utc(2000,  1, 1), Time.utc(2000,  2, 1), info)
      assert_period( :XDT, 7200, 3600,  true, Time.utc(2000,  2, 1), Time.utc(2000,  3, 1), info)
      assert_period(:XST1, 3600,    0, false, Time.utc(2000,  3, 1),                   nil, info)
    end
  end

  def test_load_offset_does_not_use_equal_utc_total_offset_equal_after
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST1'},
      {:gmtoff => 7200, :isdst => false, :abbrev => 'XST2'},
      {:gmtoff => 7200, :isdst => true,  :abbrev => 'XDT'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 1},
      {:at => Time.utc(2000,  2, 1), :offset_index => 3},
      {:at => Time.utc(2000,  3, 1), :offset_index => 2}]

    # XDT will be based on the utc_offset of XST1 even though XST2 has an
    # equivalent (or greater) utc_total_offset.

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/UtcOffsetEqual', path)
      assert_equal('Zone/UtcOffsetEqual', info.identifier)

      assert_period( :LMT, 3542,    0, false,                   nil, Time.utc(2000,  1, 1), info)
      assert_period(:XST1, 3600,    0, false, Time.utc(2000,  1, 1), Time.utc(2000,  2, 1), info)
      assert_period( :XDT, 3600, 3600,  true, Time.utc(2000,  2, 1), Time.utc(2000,  3, 1), info)
      assert_period(:XST2, 7200,    0, false, Time.utc(2000,  3, 1),                   nil, info)
    end
  end

  def test_load_offset_does_not_use_equal_utc_total_offset_equal_before
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST1'},
      {:gmtoff => 7200, :isdst => false, :abbrev => 'XST2'},
      {:gmtoff => 7200, :isdst => true,  :abbrev => 'XDT'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 2},
      {:at => Time.utc(2000,  2, 1), :offset_index => 3},
      {:at => Time.utc(2000,  3, 1), :offset_index => 1}]

    # XDT will be based on the utc_offset of XST1 even though XST2 has an
    # equivalent (or greater) utc_total_offset.

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/UtcOffsetEqual', path)
      assert_equal('Zone/UtcOffsetEqual', info.identifier)

      assert_period( :LMT, 3542,    0, false,                   nil, Time.utc(2000,  1, 1), info)
      assert_period(:XST2, 7200,    0, false, Time.utc(2000,  1, 1), Time.utc(2000,  2, 1), info)
      assert_period( :XDT, 3600, 3600,  true, Time.utc(2000,  2, 1), Time.utc(2000,  3, 1), info)
      assert_period(:XST1, 3600,    0, false, Time.utc(2000,  3, 1),                   nil, info)
    end
  end

  def test_load_offset_both_adjacent_non_dst_equal_utc_total_offset
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [
      {:gmtoff => 7142, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 7200, :isdst => false, :abbrev => 'XST'},
      {:gmtoff => 7200, :isdst => true,  :abbrev => 'XDT'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 1},
      {:at => Time.utc(2000,  2, 1), :offset_index => 2},
      {:at => Time.utc(2000,  3, 1), :offset_index => 1}]

    # XDT will just assume an std_offset of +1 hour and calculate the utc_offset
    # from utc_total_offset - std_offset.

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/AdjacentEqual', path)
      assert_equal('Zone/AdjacentEqual', info.identifier)

      assert_period(:LMT, 7142,    0, false,                   nil, Time.utc(2000,  1, 1), info)
      assert_period(:XST, 7200,    0, false, Time.utc(2000,  1, 1), Time.utc(2000,  2, 1), info)
      assert_period(:XDT, 3600, 3600,  true, Time.utc(2000,  2, 1), Time.utc(2000,  3, 1), info)
      assert_period(:XST, 7200,    0, false, Time.utc(2000,  3, 1),                   nil, info)
    end
  end

  def test_load_offset_utc_offset_preserved_from_next
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [
      {:gmtoff =>  3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff =>  3600, :isdst => false, :abbrev => 'XST1'},
      {:gmtoff =>  7200, :isdst => false, :abbrev => 'XST2'},
      {:gmtoff => 10800, :isdst => true,  :abbrev => 'XDT1'},
      {:gmtoff => 10800, :isdst => true,  :abbrev => 'XDT2'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 1},
      {:at => Time.utc(2000,  2, 1), :offset_index => 3},
      {:at => Time.utc(2000,  3, 1), :offset_index => 4},
      {:at => Time.utc(2000,  4, 1), :offset_index => 2}]

    # Both XDT1 and XDT2 should both use the closest utc_offset (7200) (and not
    # an equivalent utc_offset of 3600 and std_offset of 7200).

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/UtcOffsetPreserved', path)
      assert_equal('Zone/UtcOffsetPreserved', info.identifier)

      assert_period( :LMT, 3542,    0, false,                   nil, Time.utc(2000,  1, 1), info)
      assert_period(:XST1, 3600,    0, false, Time.utc(2000,  1, 1), Time.utc(2000,  2, 1), info)
      assert_period(:XDT1, 7200, 3600,  true, Time.utc(2000,  2, 1), Time.utc(2000,  3, 1), info)
      assert_period(:XDT2, 7200, 3600,  true, Time.utc(2000,  3, 1), Time.utc(2000,  4, 1), info)
      assert_period(:XST2, 7200,    0, false, Time.utc(2000,  4, 1),                   nil, info)
    end
  end

  def test_load_offset_utc_offset_preserved_from_previous
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [
      {:gmtoff =>  3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff =>  3600, :isdst => false, :abbrev => 'XST1'},
      {:gmtoff =>  7200, :isdst => false, :abbrev => 'XST2'},
      {:gmtoff => 10800, :isdst => true,  :abbrev => 'XDT1'},
      {:gmtoff => 10800, :isdst => true,  :abbrev => 'XDT2'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 2},
      {:at => Time.utc(2000,  2, 1), :offset_index => 3},
      {:at => Time.utc(2000,  3, 1), :offset_index => 4},
      {:at => Time.utc(2000,  4, 1), :offset_index => 1}]

    # Both XDT1 and XDT2 should both use the closest utc_offset (7200) (and not
    # an equivalent utc_offset of 3600 and std_offset of 7200).

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/UtcOffsetPreserved', path)
      assert_equal('Zone/UtcOffsetPreserved', info.identifier)

      assert_period( :LMT, 3542,    0, false,                   nil, Time.utc(2000,  1, 1), info)
      assert_period(:XST2, 7200,    0, false, Time.utc(2000,  1, 1), Time.utc(2000,  2, 1), info)
      assert_period(:XDT1, 7200, 3600,  true, Time.utc(2000,  2, 1), Time.utc(2000,  3, 1), info)
      assert_period(:XDT2, 7200, 3600,  true, Time.utc(2000,  3, 1), Time.utc(2000,  4, 1), info)
      assert_period(:XST1, 3600,    0, false, Time.utc(2000,  4, 1),                   nil, info)
    end
  end

  def test_read_offset_negative_std_offset_dst
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [
      {:gmtoff => -100, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST'},
      {:gmtoff =>    0, :isdst => true,  :abbrev => 'XWT'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 1},
      {:at => Time.utc(2000,  2, 1), :offset_index => 2},
      {:at => Time.utc(2000,  3, 1), :offset_index => 1},
      {:at => Time.utc(2000,  4, 1), :offset_index => 2},
      {:at => Time.utc(2000,  5, 1), :offset_index => 1}]

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/NegativeStdOffsetDst', path)
      assert_equal('Zone/NegativeStdOffsetDst', info.identifier)

      assert_period(:LMT, -100,     0, false,                  nil, Time.utc(2000, 1, 1), info)
      assert_period(:XST, 3600,     0, false, Time.utc(2000, 1, 1), Time.utc(2000, 2, 1), info)
      assert_period(:XWT, 3600, -3600,  true, Time.utc(2000, 2, 1), Time.utc(2000, 3, 1), info)
      assert_period(:XST, 3600,     0, false, Time.utc(2000, 3, 1), Time.utc(2000, 4, 1), info)
      assert_period(:XWT, 3600, -3600,  true, Time.utc(2000, 4, 1), Time.utc(2000, 5, 1), info)
      assert_period(:XST, 3600,     0, false, Time.utc(2000, 5, 1),                  nil, info)
    end
  end

  def test_read_offset_negative_std_offset_dst_initial_dst
    # The zoneinfo files don't include the offset from standard time, so this
    # has to be derived by looking at changes in the total UTC offset.

    offsets = [
      {:gmtoff => -100, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff =>    0, :isdst => true,  :abbrev => 'XWT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 1},
      {:at => Time.utc(2000,  2, 1), :offset_index => 2},
      {:at => Time.utc(2000,  3, 1), :offset_index => 1},
      {:at => Time.utc(2000,  4, 1), :offset_index => 2},
      {:at => Time.utc(2000,  5, 1), :offset_index => 1}]

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/NegativeStdOffsetDstInitialDst', path)
      assert_equal('Zone/NegativeStdOffsetDstInitialDst', info.identifier)

      assert_period(:LMT, -100,     0, false,                  nil, Time.utc(2000, 1, 1), info)
      assert_period(:XWT, 3600, -3600,  true, Time.utc(2000, 1, 1), Time.utc(2000, 2, 1), info)
      assert_period(:XST, 3600,     0, false, Time.utc(2000, 2, 1), Time.utc(2000, 3, 1), info)
      assert_period(:XWT, 3600, -3600,  true, Time.utc(2000, 3, 1), Time.utc(2000, 4, 1), info)
      assert_period(:XST, 3600,     0, false, Time.utc(2000, 4, 1), Time.utc(2000, 5, 1), info)
      assert_period(:XWT, 3600, -3600,  true, Time.utc(2000, 5, 1),                  nil, info)
    end
  end

  def test_read_offset_prefer_base_offset_moves_to_dst_not_hour
    offsets = [
      {:gmtoff => -100, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff =>    0, :isdst => false, :abbrev => 'XST'},
      {:gmtoff => 1800, :isdst => true,  :abbrev => 'XDT'},
      {:gmtoff => 1800, :isdst => false, :abbrev => 'XST'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 1},
      {:at => Time.utc(2000,  2, 1), :offset_index => 2},
      {:at => Time.utc(2000,  3, 1), :offset_index => 3}]

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/BaseOffsetMovesToDstNotHour', path)
      assert_equal('Zone/BaseOffsetMovesToDstNotHour', info.identifier)

      assert_period(:LMT, -100,     0, false,                  nil, Time.utc(2000, 1, 1), info)
      assert_period(:XST,    0,     0, false, Time.utc(2000, 1, 1), Time.utc(2000, 2, 1), info)
      assert_period(:XDT,    0,  1800,  true, Time.utc(2000, 2, 1), Time.utc(2000, 3, 1), info)
      assert_period(:XST, 1800,     0, false, Time.utc(2000, 3, 1),                  nil, info)
    end
  end

  def test_read_offset_prefer_base_offset_moves_from_dst_not_hour
    offsets = [
      {:gmtoff => -100, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 1800, :isdst => false, :abbrev => 'XST'},
      {:gmtoff => 1800, :isdst => true,  :abbrev => 'XDT'},
      {:gmtoff =>    0, :isdst => false, :abbrev => 'XST'}]

    transitions = [
      {:at => Time.utc(2000,  1, 1), :offset_index => 1},
      {:at => Time.utc(2000,  2, 1), :offset_index => 2},
      {:at => Time.utc(2000,  3, 1), :offset_index => 3}]

    tzif_test(offsets, transitions) do |path, format|
      info = ZoneinfoTimezoneInfo.new('Zone/BaseOffsetMovesFromDstNotHour', path)
      assert_equal('Zone/BaseOffsetMovesFromDstNotHour', info.identifier)

      assert_period(:LMT, -100,     0, false,                  nil, Time.utc(2000, 1, 1), info)
      assert_period(:XST, 1800,     0, false, Time.utc(2000, 1, 1), Time.utc(2000, 2, 1), info)
      assert_period(:XDT,    0,  1800,  true, Time.utc(2000, 2, 1), Time.utc(2000, 3, 1), info)
      assert_period(:XST,    0,     0, false, Time.utc(2000, 3, 1),                  nil, info)
    end
  end
  
  def test_load_in_safe_mode
    offsets = [{:gmtoff => -12094, :isdst => false, :abbrev => 'LT'}]
        
    tzif_test(offsets, []) do |path, format|
      # untaint only required for Ruby 1.9.2
      path.untaint
      
      safe_test do        
        info = ZoneinfoTimezoneInfo.new('Zone/three', path)
        assert_equal('Zone/three', info.identifier)
        
        assert_period(:LT, -12094, 0, false, nil, nil, info)
      end
    end
  end
  
  def test_load_encoding
    # tzfile.5 doesn't specify an encoding, but the source data is in ASCII.
    # ZoneinfoTimezoneInfo will load as UTF-8 (a superset of ASCII).
  
    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST©'}]
      
    transitions = [
      {:at => Time.utc(1971,  1,  2), :offset_index => 1}]
  
    tzif_test(offsets, transitions) do |path, format|     
      info = ZoneinfoTimezoneInfo.new('Zone/One', path)
      assert_equal('Zone/One', info.identifier)
      
      assert_period(:LMT,     3542,    0, false,                    nil, Time.utc(1971,  1,  2), info)
      assert_period(:"XST©",  3600,    0, false, Time.utc(1971,  1,  2),                    nil, info)
    end
  end
  
  def test_load_binmode
    offsets = [
      {:gmtoff => 3542, :isdst => false, :abbrev => 'LMT'},
      {:gmtoff => 3600, :isdst => false, :abbrev => 'XST'}]
      
    # Transition time that includes CRLF (4EFF0D0A).
    # Test that this doesn't get corrupted by translating CRLF to LF.
    transitions = [
      {:at => Time.utc(2011, 12, 31, 13, 24, 26), :offset_index => 1}]
  
    tzif_test(offsets, transitions) do |path, format|     
      info = ZoneinfoTimezoneInfo.new('Zone/One', path)
      assert_equal('Zone/One', info.identifier)
      
      assert_period(:LMT, 3542, 0, false,                                nil, Time.utc(2011, 12, 31, 13, 24, 26), info)
      assert_period(:XST, 3600, 0, false, Time.utc(2011, 12, 31, 13, 24, 26),                                nil, info)
    end
  end
end