require 'test/unit'

require 'facet/fileutils/head'
require 'facet/fileutils/slice'
require 'facet/fileutils/tail'


class TC_FileUtils_HeadTail < Test::Unit::TestCase
   
  def setup
    @workdir = Dir.getwd
    @thisdir = File.dirname(__FILE__)
    
    @tfile = 'test_file.txt'
    
    @expected_head1 = ["line1\n","line2\n","line3\n","line4\n","line5\n"]
    @expected_head1.push("line6\n","line7\n","line8\n","line9\n","line10\n")
    @expected_head2 = ["line1\n","line2\n","line3\n","line4\n","line5\n"]
    
    @expected_tail1 = ["line16\n","line17\n","line18\n","line19\n","line20\n"]
    @expected_tail1.push("line21\n","line22\n","line23\n","line24\n","line25\n")
    @expected_tail2 = ["line21\n","line22\n","line23\n","line24\n","line25\n"]
    
    @expected_body1 = ["line10\n", "line11\n", "line12\n", "line13\n", "line14\n"]
    @expected_body1.push("line15\n","line16\n", "line17\n", "line18\n", "line19\n","line20\n")
    @expected_body2 = ["line14\n","line15\n","line16\n","line17\n","line18\n","line19\n","line20\n"]
    @expected_body3 = ["line5\n","line6\n","line7\n","line8\n","line9\n","line10\n"]
  end

  def test_method
    assert_respond_to( FileUtils, :head )
    assert_respond_to( FileUtils, :tail )
    assert_respond_to( FileUtils, :slice )
  end

  def test_head
    Dir.chdir @thisdir
    begin
    assert_nothing_raised{ FileUtils.head(@tfile) }
    assert_nothing_raised{ FileUtils.head(@tfile,5) }
    assert_equal(@expected_head1,FileUtils.head(@tfile))
    assert_equal(@expected_head2,FileUtils.head(@tfile,5))
    ensure
      Dir.chdir @workdir
    end
  end

  def test_tail
    Dir.chdir @thisdir
    begin
      assert_nothing_raised{ FileUtils.tail(@tfile) }
      assert_nothing_raised{ FileUtils.tail(@tfile,5) }
      assert_equal(@expected_tail1,FileUtils.tail(@tfile))
      assert_equal(@expected_tail2,FileUtils.tail(@tfile,5))
    ensure
      Dir.chdir @workdir
    end
  end
   
  def test_slice
    Dir.chdir @thisdir
    begin
      assert_nothing_raised{ FileUtils.slice(@tfile,5,10) }
      assert_equal(@expected_body3,FileUtils.slice(@tfile,5,10))
    ensure
      Dir.chdir @workdir
    end
  end
   
end