## String#word_wrap

    require 'facets/string/word_wrap'

    e = "abcde\n12345\nxyzwu\n"
    r = "abcde 12345 xyzwu".word_wrap(5)
    r.assert == e

    e = "abcd\n1234\nxyzw\n"
    r = "abcd 1234 xyzw".word_wrap(4)
    r.assert == e

    e = "abc\n123\n"
    r = "abc 123".word_wrap(4)
    r.assert == e

    e = "abc \n123\n"
    r = "abc  123".word_wrap(4)
    r.assert == e

    e = "abc \n123\n"
    r = "abc     123".word_wrap(4)
    r.assert == e

## String#word_wrap!

    w = "abcde 12345 xyzwu"
    w.word_wrap!(5)
    w.assert == "abcde\n12345\nxyzwu\n"

    w = "abcd 1234 xyzw"
    w.word_wrap!(4)
    w.assert == "abcd\n1234\nxyzw\n"

    w = "abc 123"
    w.word_wrap!(4)
    w.assert == "abc\n123\n"

    w = "abc  123"
    w.word_wrap!(4)
    w.assert == "abc \n123\n"

    w = "abc     123"
    w.word_wrap!(4)
    w.assert == "abc \n123\n"

    # Unit :word_wrap do
    #   assert_equal "abcde-\n12345-\nxyzwu\n", "abcde12345xyzwu".word_wrap(6,2)
    #   assert_equal "abcd-\n1234-\nxyzw\n", "abcd1234xyzw".word_wrap(5,2)
    #   assert_equal "abc \n123\n", "abc 123".word_wrap(4,2)
    #   assert_equal "abc \n123\n", "abc  123".word_wrap(4,2)
    #   assert_equal "abc \n123\n", "abc     123".word_wrap(4,2)
    # end

