import pytest

def test_addition():
    import operator
    assert 'a' + 'b' == 'ab'
    raises(TypeError, operator.add, b'a', 'b')

def test_getitem():
    assert u'abc'[2] == 'c'
    raises(IndexError, u'abc'.__getitem__, 15)
    assert u'g\u0105\u015b\u0107'[2] == u'\u015b'

def test_join():
    def check(a, b):
        assert a == b
        assert type(a) == type(b)
    check(', '.join(['a']), 'a')
    check(', '.join(['a', 'b']), 'a, b')
    raises(TypeError, ','.join, [b'a'])
    check(','.join(iter([])), '')
    with raises(TypeError) as exc:
        ''.join(['a', 2, 3])
    assert 'sequence item 1' in str(exc.value)
    with raises(TypeError) as exc:
        ''.join(iter(['a', 2, 3]))
    assert 'sequence item 1' in str(exc.value)
    # unicode lists
    check(''.join(['\u1234']), '\u1234')
    check(''.join(['\u1234', '\u2345']), '\u1234\u2345')
    check('\u1234'.join(['\u2345', '\u3456']), '\u2345\u1234\u3456')
    check('x\u1234y'.join(['a', 'b', 'c']), 'ax\u1234ybx\u1234yc')
    # also checking passing a single unicode instead of a list
    check(''.join('\u1234'), '\u1234')
    check(''.join('\u1234\u2345'), '\u1234\u2345')
    check('\u1234'.join('\u2345\u3456'), '\u2345\u1234\u3456')

def test_contains():
    assert '' in 'abc'
    assert 'a' in 'abc'
    assert 'bc' in 'abc'
    assert '\xe2' in 'g\xe2teau'

def test_splitlines():
    assert ''.splitlines() == []
    assert ''.splitlines(1) == []
    assert '\n'.splitlines() == ['']
    assert 'a'.splitlines() == ['a']
    assert 'one\ntwo'.splitlines() == ['one', 'two']
    assert '\ntwo\nthree'.splitlines() == ['', 'two', 'three']
    assert '\n\n'.splitlines() == ['', '']
    assert 'a\nb\nc'.splitlines(1) == ['a\n', 'b\n', 'c']
    assert '\na\nb\n'.splitlines(1) == ['\n', 'a\n', 'b\n']
    assert ((u'a' + b'\xc2\x85'.decode('utf8') + u'b\n').splitlines() ==
            ['a', 'b'])

def test_zfill():
    assert '123'.zfill(2) == '123'
    assert '123'.zfill(3) == '123'
    assert '123'.zfill(4) == '0123'
    assert '123'.zfill(6) == '000123'
    assert '+123'.zfill(2) == '+123'
    assert '+123'.zfill(3) == '+123'
    assert '+123'.zfill(4) == '+123'
    assert '+123'.zfill(5) == '+0123'
    assert '+123'.zfill(6) == '+00123'
    assert '-123'.zfill(3) == '-123'
    assert '-123'.zfill(4) == '-123'
    assert '-123'.zfill(5) == '-0123'
    assert ''.zfill(3) == '000'
    assert '34'.zfill(1) == '34'
    assert '34'.zfill(4) == '0034'

def test_split():
    assert "".split() == []
    assert "".split('x') == ['']
    assert " ".split() == []
    assert "a".split() == ['a']
    assert "a".split("a", 1) == ['', '']
    assert " ".split(" ", 1) == ['', '']
    assert "aa".split("a", 2) == ['', '', '']
    assert " a ".split() == ['a']
    assert "a b c".split() == ['a','b','c']
    assert 'this is the split function'.split() == ['this', 'is', 'the', 'split', 'function']
    assert 'a|b|c|d'.split('|') == ['a', 'b', 'c', 'd']
    assert 'a|b|c|d'.split('|') == ['a', 'b', 'c', 'd']
    assert 'a|b|c|d'.split('|') == ['a', 'b', 'c', 'd']
    assert 'a|b|c|d'.split('|', 2) == ['a', 'b', 'c|d']
    assert 'a b c d'.split(None, 1) == ['a', 'b c d']
    assert 'a b c d'.split(None, 2) == ['a', 'b', 'c d']
    assert 'a b c d'.split(None, 3) == ['a', 'b', 'c', 'd']
    assert 'a b c d'.split(None, 4) == ['a', 'b', 'c', 'd']
    assert 'a b c d'.split(None, 0) == ['a b c d']
    assert 'a  b  c  d'.split(None, 2) == ['a', 'b', 'c  d']
    assert 'a b c d '.split() == ['a', 'b', 'c', 'd']
    assert 'a//b//c//d'.split('//') == ['a', 'b', 'c', 'd']
    assert 'endcase test'.split('test') == ['endcase ', '']
    raises(ValueError, 'abc'.split, '')
    raises(ValueError, 'abc'.split, '')
    raises(ValueError, 'abc'.split, '')
    assert '   a b c d'.split(None, 0) == ['a b c d']
    assert u'a\nb\u1680c'.split() == [u'a', u'b', u'c']

def test_rsplit():
    assert u"".rsplit() == []
    assert u" ".rsplit() == []
    assert u"a".rsplit() == [u'a']
    assert u"a".rsplit(u"a", 1) == [u'', u'']
    assert u" ".rsplit(u" ", 1) == [u'', u'']
    assert u"aa".rsplit(u"a", 2) == [u'', u'', u'']
    assert u" a ".rsplit() == [u'a']
    assert u"a b c".rsplit() == [u'a',u'b',u'c']
    assert u'this is the rsplit function'.rsplit() == [u'this', u'is', u'the', u'rsplit', u'function']
    assert u'a|b|c|d'.rsplit(u'|') == [u'a', u'b', u'c', u'd']
    assert u'a|b|c|d'.rsplit('|') == [u'a', u'b', u'c', u'd']
    assert 'a|b|c|d'.rsplit(u'|') == [u'a', u'b', u'c', u'd']
    assert u'a|b|c|d'.rsplit(u'|', 2) == [u'a|b', u'c', u'd']
    assert u'a b c d'.rsplit(None, 1) == [u'a b c', u'd']
    assert u'a b c d'.rsplit(None, 2) == [u'a b', u'c', u'd']
    assert u'a b c d'.rsplit(None, 3) == [u'a', u'b', u'c', u'd']
    assert u'a b c d'.rsplit(None, 4) == [u'a', u'b', u'c', u'd']
    assert u'a b c d'.rsplit(None, 0) == [u'a b c d']
    assert u'a  b  c  d'.rsplit(None, 2) == [u'a  b', u'c', u'd']
    assert u'a b c d '.rsplit() == [u'a', u'b', u'c', u'd']
    assert u'a//b//c//d'.rsplit(u'//') == [u'a', u'b', u'c', u'd']
    assert u'endcase test'.rsplit(u'test') == [u'endcase ', u'']
    raises(ValueError, u'abc'.rsplit, u'')
    raises(ValueError, u'abc'.rsplit, '')
    raises(ValueError, 'abc'.rsplit, u'')
    assert u'  a b c  '.rsplit(None, 0) == [u'  a b c']
    assert u''.rsplit('aaa') == [u'']
    assert u'a\nb\u1680c'.rsplit() == [u'a', u'b', u'c']

def test_rsplit_bug():
    assert u'Vestur- og Mið'.rsplit() == [u'Vestur-', u'og', u'Mið']

def test_center():
    s=u"a b"
    assert s.center(0) == u"a b"
    assert s.center(1) == u"a b"
    assert s.center(2) == u"a b"
    assert s.center(3) == u"a b"
    assert s.center(4) == u"a b "
    assert s.center(5) == u" a b "
    assert s.center(6) == u" a b  "
    assert s.center(7) == u"  a b  "
    assert s.center(8) == u"  a b   "
    assert s.center(9) == u"   a b   "
    assert u'abc'.center(10) == u'   abc    '
    assert u'abc'.center(6) == u' abc  '
    assert u'abc'.center(3) == u'abc'
    assert u'abc'.center(2) == u'abc'
    assert u'abc'.center(5, u'*') == u'*abc*'    # Python 2.4
    assert u'abc'.center(5, '*') == u'*abc*'     # Python 2.4
    raises(TypeError, u'abc'.center, 4, u'cba')
    assert 'x'.center(2, u'\U0010FFFF') == u'x\U0010FFFF'

def test_title():
    assert "brown fox".title() == "Brown Fox"
    assert "!brown fox".title() == "!Brown Fox"
    assert "bROWN fOX".title() == "Brown Fox"
    assert "Brown Fox".title() == "Brown Fox"
    assert "bro!wn fox".title() == "Bro!Wn Fox"
    assert u'A\u03a3 \u1fa1xy'.title() == u'A\u03c2 \u1fa9xy'
    assert u'A\u03a3A'.title() == u'A\u03c3a'
    assert u"brow\u4321n fox".title() == u"Brow\u4321N Fox"
    assert u'\ud800'.title() == u'\ud800'
    assert (chr(0x345) + u'abc').title() == u'\u0399abc'
    assert (chr(0x345) + u'ABC').title() == u'\u0399abc'

def test_title_bug():
    assert (chr(496) + "abc").title() == 'J̌abc'

def test_istitle():
    assert u"".istitle() == False
    assert u"!".istitle() == False
    assert u"!!".istitle() == False
    assert u"brown fox".istitle() == False
    assert u"!brown fox".istitle() == False
    assert u"bROWN fOX".istitle() == False
    assert u"Brown Fox".istitle() == True
    assert u"bro!wn fox".istitle() == False
    assert u"Bro!wn fox".istitle() == False
    assert u"!brown Fox".istitle() == False
    assert u"!Brown Fox".istitle() == True
    assert u"Brow&&&&N Fox".istitle() == True
    assert u"!Brow&&&&n Fox".istitle() == False
    assert u'\u1FFc'.istitle()
    assert u'Greek \u1FFcitlecases ...'.istitle()

def test_islower_isupper_with_titlecase():
    # \u01c5 is a char which is neither lowercase nor uppercase, but
    # titlecase
    assert not '\u01c5abc'.islower()
    assert not '\u01c5ABC'.isupper()

def test_islower():
    assert u'\u2177'.islower()

def test_isidentifier():
    assert "".isidentifier() is False
    assert "a4".isidentifier() is True
    assert "_var".isidentifier() is True
    assert "_!var".isidentifier() is False
    assert "3abc".isidentifier() is False

def test_lower_upper():
    assert u'a'.lower() == u'a'
    assert u'A'.lower() == u'a'
    assert u'\u0105'.lower() == u'\u0105'
    assert u'\u0104'.lower() == u'\u0105'
    assert u'\ud800'.lower() == u'\ud800'
    assert u'a'.upper() == u'A'
    assert u'A'.upper() == u'A'
    assert u'\u0105'.upper() == u'\u0104'
    assert u'\u0104'.upper() == u'\u0104'
    assert u'\ud800'.upper() == u'\ud800'

def test_capitalize():
    assert u'A\u0345\u03a3'.capitalize() == u'A\u0345\u03c2'
    assert u"brown fox".capitalize() == u"Brown fox"
    assert u' hello '.capitalize() == u' hello '
    assert u'Hello '.capitalize() == u'Hello '
    assert u'hello '.capitalize() == u'Hello '
    assert u'aaaa'.capitalize() == u'Aaaa'
    assert u'AaAa'.capitalize() == u'Aaaa'
    # check that titlecased chars are lowered correctly
    # \u1ffc is the titlecased char
    assert (u'\u1ff3\u1ff3\u1ffc\u1ffc'.capitalize() ==
            u'\u1ffc\u1ff3\u1ff3\u1ff3')
    # check with cased non-letter chars
    assert (u'\u24c5\u24ce\u24c9\u24bd\u24c4\u24c3'.capitalize() ==
            u'\u24c5\u24e8\u24e3\u24d7\u24de\u24dd')
    assert (u'\u24df\u24e8\u24e3\u24d7\u24de\u24dd'.capitalize() ==
            u'\u24c5\u24e8\u24e3\u24d7\u24de\u24dd')
    assert u'\u2160\u2161\u2162'.capitalize() == u'\u2160\u2171\u2172'
    assert u'\u2170\u2171\u2172'.capitalize() == u'\u2160\u2171\u2172'
    # check with Ll chars with no upper - nothing changes here
    assert ('\u019b\u1d00\u1d86\u0221\u1fb7'.capitalize() ==
            '\u019b\u1d00\u1d86\u0221\u1fb7')
    # cpython issue 17252 for i_dot
    assert u'h\u0130'.capitalize() == u'H\u0069\u0307'

def test_capitalize_bug_38():
    assert 'finnish'.capitalize() == "Finnish"

def test_changed_in_unicodedata_version_8():
    assert u'\u025C'.upper() == u'\uA7AB'

def test_isprintable():
    assert "".isprintable()
    assert " ".isprintable()
    assert "abcdefg".isprintable()
    assert not "abcdefg\n".isprintable()
    # some defined Unicode character
    assert "\u0374".isprintable()
    # undefined character
    assert not "\u0378".isprintable()
    # single surrogate character
    assert not "\ud800".isprintable()

def test_isascii():
    assert "".isascii()
    assert "abcdefg\t".isascii()
    assert not "abc\u0374".isascii()
    assert not "\ud800abc".isascii()

def test_rjust():
    s = u"abc"
    assert s.rjust(2) == s
    assert s.rjust(3) == s
    assert s.rjust(4) == u" " + s
    assert s.rjust(5) == u"  " + s
    assert u'abc'.rjust(10) == u'       abc'
    assert u'abc'.rjust(6) == u'   abc'
    assert u'abc'.rjust(3) == u'abc'
    assert u'abc'.rjust(2) == u'abc'
    assert u'abc'.rjust(5, u'*') == u'**abc'    # Python 2.4
    assert u'abc'.rjust(5, '*') == u'**abc'     # Python 2.4
    raises(TypeError, u'abc'.rjust, 5, u'xx')

def test_ljust():
    s = u"abc"
    assert s.ljust(2) == s
    assert s.ljust(3) == s
    assert s.ljust(4) == s + u" "
    assert s.ljust(5) == s + u"  "
    assert u'abc'.ljust(10) == u'abc       '
    assert u'abc'.ljust(6) == u'abc   '
    assert u'abc'.ljust(3) == u'abc'
    assert u'abc'.ljust(2) == u'abc'
    assert u'abc'.ljust(5, u'*') == u'abc**'    # Python 2.4
    assert u'abc'.ljust(5, '*') == u'abc**'     # Python 2.4
    raises(TypeError, u'abc'.ljust, 6, u'')

def test_replace():
    assert 'one!two!three!'.replace('!', '@', 1) == 'one@two!three!'
    assert 'one!two!three!'.replace('!', '') == 'onetwothree'
    assert 'one!two!three!'.replace('!', '@', 2) == 'one@two@three!'
    assert 'one!two!three!'.replace('!', '@', 3) == 'one@two@three@'
    assert 'one!two!three!'.replace('!', '@', 4) == 'one@two@three@'
    assert 'one!two!three!'.replace('!', '@', 0) == 'one!two!three!'
    assert 'one!two!three!'.replace('!', '@') == 'one@two@three@'
    assert 'one!two!three!'.replace('x', '@') == 'one!two!three!'
    assert 'one!two!three!'.replace('x', '@', 2) == 'one!two!three!'
    assert u'\u1234'.replace(u'', '-') == u'-\u1234-'
    assert u'\u0234\u5678'.replace('', u'-') == u'-\u0234-\u5678-'
    assert u'\u0234\u5678'.replace('', u'-', 0) == u'\u0234\u5678'
    assert u'\u0234\u5678'.replace('', u'-', 1) == u'-\u0234\u5678'
    assert u'\u0234\u5678'.replace('', u'-', 2) == u'-\u0234-\u5678'
    assert u'\u0234\u5678'.replace('', u'-', 3) == u'-\u0234-\u5678-'
    assert u'\u0234\u5678'.replace('', u'-', 4) == u'-\u0234-\u5678-'
    assert u'\u0234\u5678'.replace('', u'-', 700) == u'-\u0234-\u5678-'
    assert u'\u0234\u5678'.replace('', u'-', -1) == u'-\u0234-\u5678-'
    assert u'\u0234\u5678'.replace('', u'-', -42) == u'-\u0234-\u5678-'
    assert 'abc'.replace('', '-') == '-a-b-c-'
    assert 'abc'.replace('', '-', 3) == '-a-b-c'
    assert 'abc'.replace('', '-', 0) == 'abc'
    assert ''.replace('', '') == ''
    assert ''.replace('', 'a') == 'a'
    assert 'abc'.replace('ab', '--', 0) == 'abc'
    assert 'abc'.replace('xy', '--') == 'abc'
    assert '123'.replace('123', '') == ''
    assert '123123'.replace('123', '') == ''
    assert '123x123'.replace('123', '') == 'x'

def test_replace_overflow():
    import sys
    if sys.maxsize > 2**31-1:
        skip("Wrong platform")
    s = "a" * (2**16)
    raises(OverflowError, s.replace, "", s)

def test_empty_replace_empty():
    assert "".replace("", "a", 0) == ""
    assert "".replace("", "a", 1) == "a"
    assert "".replace("", "a", 121344) == "a"

def test_strip():
    s = " a b "
    assert s.strip() == "a b"
    assert s.rstrip() == " a b"
    assert s.lstrip() == "a b "
    assert 'xyzzyhelloxyzzy'.strip('xyz') == 'hello'
    assert 'xyzzyhelloxyzzy'.lstrip('xyz') == 'helloxyzzy'
    assert 'xyzzyhelloxyzzy'.rstrip('xyz') == 'xyzzyhello'
    raises(TypeError, s.strip, bytearray(b'a'))

def test_strip_nonascii():
    assert 'c\x1d'.strip() == 'c'
    s = u" ä b "
    assert s.strip() == u"ä b"
    assert s.rstrip() == u" ä b"
    assert s.lstrip() == u"ä b "
    assert u'xyzzyh³lloxyzzy'.strip(u'xyzü') == u'h³llo'
    assert u'xyzzyh³lloxyzzy'.lstrip(u'xyzü') == u'h³lloxyzzy'
    assert u'xyzzyh³lloxyzzy'.rstrip(u'xyzü') == u'xyzzyh³llo'


def test_rstrip_bug():
    assert u"aaaaaaaaaaaaaaaaaaa".rstrip(u"a") == u""
    assert u"äääääääääääääääääääääääää".rstrip(u"ä") == u""

def test_long_from_unicode():
    assert int('12345678901234567890') == 12345678901234567890
    assert int('123', 7) == 66

def test_int_from_unicode():
    assert int('12345') == 12345

def test_float_from_unicode():
    assert float('123.456e89') == float('123.456e89')

def test_repr_16bits():
    # this used to fail when run on a CPython host with 16-bit unicodes
    s = repr('\U00101234')
    assert s == "'\\U00101234'"

def test_repr():
    for ustr in ["", "a", "'", "\'", "\"", "\t", "\\", '',
                 'a', '"', '\'', '\"', '\t', '\\', "'''\"",
                 chr(19), chr(2), '\u1234', '\U00101234', '\U0001f42a']:
        assert eval(repr(ustr)) == ustr

def test_getnewargs():
    class X(str):
        pass
    x = X("foo\u1234")
    a = x.__getnewargs__()
    assert a == ("foo\u1234",)
    assert type(a[0]) is str

def test_call_unicode():
    assert str() == ''
    assert str(None) == 'None'
    assert str(123) == '123'
    assert str(object=123) == '123'
    assert str([2, 3]) == '[2, 3]'
    assert str(errors='strict') == ''
    class U(str):
        pass
    assert str(U()).__class__ is str
    assert U().__str__().__class__ is str
    assert U('test') == 'test'
    assert U('test').__class__ is U
    assert U(errors='strict') == U('')

def test_call_unicode_2():
    class X(object):
        def __bytes__(self):
            return b'x'
    raises(TypeError, str, X(), 'ascii')

def test_startswith():
    assert 'ab'.startswith('ab') is True
    assert 'ab'.startswith('a') is True
    assert 'ab'.startswith('') is True
    assert 'x'.startswith('a') is False
    assert 'x'.startswith('x') is True
    assert ''.startswith('') is True
    assert ''.startswith('a') is False
    assert 'x'.startswith('xx') is False
    assert 'y'.startswith('xx') is False
    assert u'\u1234\u5678\u4321'.startswith(u'\u1234') is True
    assert u'\u1234\u5678\u4321'.startswith(u'\u1234\u4321') is False
    assert u'\u1234'.startswith(u'') is True

def test_startswith_more():
    assert 'ab'.startswith('a', 0) is True
    assert 'ab'.startswith('a', 1) is False
    assert 'ab'.startswith('b', 1) is True
    assert 'abc'.startswith('bc', 1, 2) is False
    assert 'abc'.startswith('c', -1, 4) is True
    assert '0'.startswith('', 1, -1) is False
    assert '0'.startswith('', 1, 0) is False
    assert '0'.startswith('', 1) is True
    assert '0'.startswith('', 1, None) is True
    assert ''.startswith('', 1, -1) is False
    assert ''.startswith('', 1, 0) is False
    assert ''.startswith('', 1) is False
    assert ''.startswith('', 1, None) is False
    try:
        'hello'.startswith(['o'])
    except TypeError as e:
        msg = str(e)
        assert 'str' in msg
        assert 'tuple' in msg
    else:
        assert False, 'Expected TypeError'

def test_startswith_too_large():
    assert u'ab'.startswith(u'b', 1) is True
    assert u'ab'.startswith(u'', 2) is True
    assert u'ab'.startswith(u'', 3) is False
    assert u'ab'.endswith(u'b', 1) is True
    assert u'ab'.endswith(u'', 2) is True
    assert u'ab'.endswith(u'', 3) is False

def test_startswith_tuples():
    assert 'hello'.startswith(('he', 'ha'))
    assert not 'hello'.startswith(('lo', 'llo'))
    assert 'hello'.startswith(('hellox', 'hello'))
    assert not 'hello'.startswith(())
    assert 'helloworld'.startswith(('hellowo', 'rld', 'lowo'), 3)
    assert not 'helloworld'.startswith(('hellowo', 'ello', 'rld'), 3)
    assert 'hello'.startswith(('lo', 'he'), 0, -1)
    assert not 'hello'.startswith(('he', 'hel'), 0, 1)
    assert 'hello'.startswith(('he', 'hel'), 0, 2)
    raises(TypeError, 'hello'.startswith, (42,))

def test_startswith_endswith_convert():
    assert 'hello'.startswith(('he\u1111', 'he'))
    assert not 'hello'.startswith(('lo\u1111', 'llo'))
    assert 'hello'.startswith(('hellox\u1111', 'hello'))
    assert not 'hello'.startswith(('lo', 'he\u1111'), 0, -1)
    assert not 'hello'.endswith(('he\u1111', 'he'))
    assert 'hello'.endswith(('\u1111lo', 'llo'))
    assert 'hello'.endswith(('\u1111hellox', 'hello'))

def test_endswith():
    assert 'ab'.endswith('ab') is True
    assert 'ab'.endswith('b') is True
    assert 'ab'.endswith('') is True
    assert 'x'.endswith('a') is False
    assert 'x'.endswith('x') is True
    assert ''.endswith('') is True
    assert ''.endswith('a') is False
    assert 'x'.endswith('xx') is False
    assert 'y'.endswith('xx') is False
    assert 'x'.endswith('', 1, 0) is False
    assert ''.endswith('', 1, 9223372036854775808) is False


def test_endswith_more():
    assert 'abc'.endswith('ab', 0, 2) is True
    assert 'abc'.endswith('bc', 1) is True
    assert 'abc'.endswith('bc', 2) is False
    assert 'abc'.endswith('b', -3, -1) is True
    assert '0'.endswith('', 1, -1) is False
    try:
        'hello'.endswith(['o'])
    except TypeError as e:
        msg = str(e)
        assert 'str' in msg
        assert 'tuple' in msg
    else:
        assert False, 'Expected TypeError'

def test_endswith_tuple():
    assert not 'hello'.endswith(('he', 'ha'))
    assert 'hello'.endswith(('lo', 'llo'))
    assert 'hello'.endswith(('hellox', 'hello'))
    assert not 'hello'.endswith(())
    assert 'helloworld'.endswith(('hellowo', 'rld', 'lowo'), 3)
    assert not 'helloworld'.endswith(('hellowo', 'ello', 'rld'), 3, -1)
    assert 'hello'.endswith(('hell', 'ell'), 0, -1)
    assert not 'hello'.endswith(('he', 'hel'), 0, 1)
    assert 'hello'.endswith(('he', 'hell'), 0, 4)
    raises(TypeError, 'hello'.endswith, (42,))

def test_expandtabs():
    assert 'abc\rab\tdef\ng\thi'.expandtabs() ==    'abc\rab      def\ng       hi'
    assert 'abc\rab\tdef\ng\thi'.expandtabs(8) ==   'abc\rab      def\ng       hi'
    assert 'abc\rab\tdef\ng\thi'.expandtabs(4) ==   'abc\rab  def\ng   hi'
    assert 'abc\r\nab\tdef\ng\thi'.expandtabs(4) == 'abc\r\nab  def\ng   hi'
    assert 'abc\rab\tdef\ng\thi'.expandtabs() ==    'abc\rab      def\ng       hi'
    assert 'abc\rab\tdef\ng\thi'.expandtabs(8) ==   'abc\rab      def\ng       hi'
    assert 'abc\r\nab\r\ndef\ng\r\nhi'.expandtabs(4) == 'abc\r\nab\r\ndef\ng\r\nhi'

    s = 'xy\t'
    assert s.expandtabs() =='xy      '

    s = '\txy\t'
    assert s.expandtabs() =='        xy      '
    assert s.expandtabs(1) ==' xy '
    assert s.expandtabs(2) =='  xy  '
    assert s.expandtabs(3) =='   xy '

    assert 'xy'.expandtabs() =='xy'
    assert ''.expandtabs() ==''

def test_expandtabs_overflows_gracefully():
    import sys
    raises((OverflowError, MemoryError), 't\tt\t'.expandtabs, sys.maxsize)

def test_expandtabs_0():
    assert u'x\ty'.expandtabs(0) == u'xy'
    assert u'x\ty'.expandtabs(-42) == u'xy'

def test_expandtabs_bug():
    assert u"a\u266f\ttest".expandtabs() == u'a\u266f      test'
    assert u"a\u266f\ttest".expandtabs(0) == u'a\u266ftest'

def test_translate():
    import sys
    assert 'bbbc' == 'abababc'.translate({ord('a'):None})
    assert 'iiic' == 'abababc'.translate({ord('a'):None, ord('b'):ord('i')})
    assert 'iiix' == 'abababc'.translate({ord('a'):None, ord('b'):ord('i'), ord('c'):'x'})
    assert '<i><i><i>c' == 'abababc'.translate({ord('a'):None, ord('b'):'<i>'})
    assert 'c' == 'abababc'.translate({ord('a'):None, ord('b'):''})
    assert 'xyyx' == 'xzx'.translate({ord('z'):'yy'})
    assert 'abcd' == 'ab\0d'.translate('c')
    assert 'abcd' == 'abcd'.translate('')
    assert 'abababc'.translate({ord('a'): ''}) == 'bbbc'

    raises(TypeError, 'hello'.translate)
    raises(ValueError, "\xff".translate, {0xff: sys.maxunicode+1})
    raises(ValueError, u'x'.translate, {ord('x'):0x110000})

def test_maketrans():
    assert 'abababc' == 'abababc'.translate({'b': '<i>'})
    tbl = str.maketrans({'a': None, 'b': '<i>'})
    assert '<i><i><i>c' == 'abababc'.translate(tbl)
    tbl = str.maketrans('abc', 'xyz', 'd')
    assert 'xyzzy' == 'abdcdcbdddd'.translate(tbl)
    tbl = str.maketrans({'\xe9': 'a'})
    assert "[\xe9]".translate(tbl) == "[a]"

    raises(TypeError, str.maketrans)
    raises(ValueError, str.maketrans, 'abc', 'defg')
    raises(TypeError, str.maketrans, 2, 'def')
    raises(TypeError, str.maketrans, 'abc', 2)
    raises(TypeError, str.maketrans, 'abc', 'def', 2)
    raises(ValueError, str.maketrans, {'xy': 2})
    raises(TypeError, str.maketrans, {(1,): 2})

    raises(TypeError, 'hello'.translate)
    raises(TypeError, 'abababc'.translate, 'abc', 'xyz')

def test_maketrans_bug():
    assert str.maketrans(u'啊', u'阿') == {21834: 38463}
    assert str.maketrans(u'啊', u'a') == {21834: 97}
    assert str.maketrans(u'', u'', u'阿') == {38463: None}

def test_unicode_from_encoded_object():
    assert str(b'x', 'utf-8') == 'x'
    assert str(b'x', 'utf-8', 'strict') == 'x'

def test_unicode_startswith_tuple():
    assert 'xxx'.startswith(('x', 'y', 'z'), 0)
    assert 'xxx'.endswith(('x', 'y', 'z'), 0)

def test_missing_cases():
    # some random cases, which are discovered to not be tested during annotation
    assert 'xxx'[1:1] == ''

# these tests test lots of encodings, so they really belong to the _codecs
# module. however, they test useful unicode methods too
# they are stolen from CPython's unit tests

def test_codecs_utf7():
    utfTests = [
        ('A\u2262\u0391.', b'A+ImIDkQ.'),             # RFC2152 example
        ('Hi Mom -\u263a-!', b'Hi Mom -+Jjo--!'),     # RFC2152 example
        ('\u65E5\u672C\u8A9E', b'+ZeVnLIqe-'),        # RFC2152 example
        ('Item 3 is \u00a31.', b'Item 3 is +AKM-1.'), # RFC2152 example
        ('+', b'+-'),
        ('+-', b'+--'),
        ('+?', b'+-?'),
        ('\?', b'+AFw?'),
        ('+?', b'+-?'),
        (r'\\?', b'+AFwAXA?'),
        (r'\\\?', b'+AFwAXABc?'),
        (r'++--', b'+-+---'),
    ]

    for (x, y) in utfTests:
        assert x.encode('utf-7') == y

    # surrogates are supported
    assert str(b'+3ADYAA-', 'utf-7') == '\udc00\ud800'

    assert str(b'+AB', 'utf-7', 'replace') == '\ufffd'

def test_codecs_utf8():
    import sys
    assert ''.encode('utf-8') == b''
    assert '\u20ac'.encode('utf-8') == b'\xe2\x82\xac'
    raises(UnicodeEncodeError, '\ud800'.encode, 'utf-8')
    raises(UnicodeEncodeError, '\udc00'.encode, 'utf-8')
    raises(UnicodeEncodeError, '\udc00!'.encode, 'utf-8')
    if sys.maxunicode > 0xFFFF and len(chr(0x10000)) == 1:
        raises(UnicodeEncodeError, '\ud800\udc02'.encode, 'utf-8')
        raises(UnicodeEncodeError, '\ud84d\udc56'.encode, 'utf-8')
        raises(UnicodeEncodeError, ('\ud800\udc02'*1000).encode, 'utf-8')
    else:
        assert '\ud800\udc02'.encode('utf-8') == b'\xf0\x90\x80\x82'
        assert '\ud84d\udc56'.encode('utf-8') == b'\xf0\xa3\x91\x96'
        assert ('\ud800\udc02'*1000).encode('utf-8') == b'\xf0\x90\x80\x82'*1000
    assert (
        '\u6b63\u78ba\u306b\u8a00\u3046\u3068\u7ffb\u8a33\u306f'
        '\u3055\u308c\u3066\u3044\u307e\u305b\u3093\u3002\u4e00'
        '\u90e8\u306f\u30c9\u30a4\u30c4\u8a9e\u3067\u3059\u304c'
        '\u3001\u3042\u3068\u306f\u3067\u305f\u3089\u3081\u3067'
        '\u3059\u3002\u5b9f\u969b\u306b\u306f\u300cWenn ist das'
        ' Nunstuck git und'.encode('utf-8') ==
        b'\xe6\xad\xa3\xe7\xa2\xba\xe3\x81\xab\xe8\xa8\x80\xe3\x81'
        b'\x86\xe3\x81\xa8\xe7\xbf\xbb\xe8\xa8\xb3\xe3\x81\xaf\xe3'
        b'\x81\x95\xe3\x82\x8c\xe3\x81\xa6\xe3\x81\x84\xe3\x81\xbe'
        b'\xe3\x81\x9b\xe3\x82\x93\xe3\x80\x82\xe4\xb8\x80\xe9\x83'
        b'\xa8\xe3\x81\xaf\xe3\x83\x89\xe3\x82\xa4\xe3\x83\x84\xe8'
        b'\xaa\x9e\xe3\x81\xa7\xe3\x81\x99\xe3\x81\x8c\xe3\x80\x81'
        b'\xe3\x81\x82\xe3\x81\xa8\xe3\x81\xaf\xe3\x81\xa7\xe3\x81'
        b'\x9f\xe3\x82\x89\xe3\x82\x81\xe3\x81\xa7\xe3\x81\x99\xe3'
        b'\x80\x82\xe5\xae\x9f\xe9\x9a\x9b\xe3\x81\xab\xe3\x81\xaf'
        b'\xe3\x80\x8cWenn ist das Nunstuck git und'
    )

    # UTF-8 specific decoding tests
    assert str(b'\xf0\xa3\x91\x96', 'utf-8') == '\U00023456'
    assert str(b'\xf0\x90\x80\x82', 'utf-8') == '\U00010002'
    assert str(b'\xe2\x82\xac', 'utf-8') == '\u20ac'
    # Invalid Continuation Bytes, EOF
    raises(UnicodeDecodeError, b'\xc4\x00'.decode, 'utf-8')
    raises(UnicodeDecodeError, b'\xe2\x82'.decode, 'utf-8')
    # Non-Canonical Forms
    raises(UnicodeDecodeError, b'\xc0\x80'.decode, 'utf-8')
    raises(UnicodeDecodeError, b'\xc1\xbf'.decode, 'utf-8')
    raises(UnicodeDecodeError, b'\xe0\x9f\xbf'.decode, 'utf-8')
    raises(UnicodeDecodeError, b'\xf0\x8f\x8f\x84'.decode, 'utf-8')
    raises(UnicodeDecodeError, b'\xf5\x80\x81\x82'.decode, 'utf-8')
    raises(UnicodeDecodeError, b'\xf4\x90\x80\x80'.decode, 'utf-8')
    # CESU-8
    raises(UnicodeDecodeError, b'\xed\xa0\xbc\xed\xb2\xb1'.decode, 'utf-8')

def test_encode_fast_path_bug_position():
    info = raises(UnicodeEncodeError, "ää\ud800".encode, "utf-8")
    assert info.value.start == 2 # used to be 4

def test_invalid_lookup():

    raises(LookupError, u"abcd".encode, "hex")
    raises(LookupError, b"abcd".decode, "hex")

def test_repr_printable():
    # PEP 3138: __repr__ respects printable characters.
    x = '\u027d'
    y = "'\u027d'"
    assert (repr(x) == y)
    x = '\U00090418\u027d\U000582b9\u54c3\U000fcb6e'
    y = "'\\U00090418\u027d\\U000582b9\u54c3\\U000fcb6e'"
    assert (repr(x) == y)
    assert (repr('\n') ==
            "'\\n'")


def test_partition():
    assert (u'this is the par', u'ti', u'tion method') == \
        u'this is the partition method'.partition(u'ti')

    # from raymond's original specification
    S = u'http://www.python.org'
    assert (u'http', u'://', u'www.python.org') == S.partition(u'://')
    assert (u'http://www.python.org', u'', u'') == S.partition(u'?')
    assert (u'', u'http://', u'www.python.org') == S.partition(u'http://')
    assert (u'http://www.python.', u'org', u'') == S.partition(u'org')

    raises(ValueError, S.partition, u'')
    raises(TypeError, S.partition, None)

def test_rpartition():
    assert (u'this is the rparti', u'ti', u'on method') == \
        u'this is the rpartition method'.rpartition(u'ti')

    # from raymond's original specification
    S = u'http://www.python.org'
    assert (u'http', u'://', u'www.python.org') == S.rpartition(u'://')
    assert (u'', u'', u'http://www.python.org') == S.rpartition(u'?')
    assert (u'', u'http://', u'www.python.org') == S.rpartition(u'http://')
    assert (u'http://www.python.', u'org', u'') == S.rpartition(u'org')

    raises(ValueError, S.rpartition, u'')
    raises(TypeError, S.rpartition, None)

def test_mul():
    zero = 0
    assert type('' * zero) == type(zero * '') is str
    assert '' * zero == zero * '' == ''
    assert 'x' * zero == zero * 'x' == ''
    assert type('x' * zero) == type(zero * 'x') is str
    assert '123' * zero == zero * '123' == ''
    assert type('123' * zero) == type(zero * '123') is str
    for i in range(10):
        u = '123' * i
        assert len(u) == 3*i
        for j in range(0, i, 3):
            assert u[j+0] == '1'
            assert u[j+1] == '2'
            assert u[j+2] == '3'
        assert '123' * i == i * '123'

def test_index():
    assert "rrarrrrrrrrra".index('a', 4, None) == 12
    assert "rrarrrrrrrrra".index('a', None, 6) == 2
    assert u"\u1234\u4321\u5678".index(u'\u5678', 1) == 2

def test_rindex():
    from sys import maxsize
    assert 'abcdefghiabc'.rindex('') == 12
    assert 'abcdefghiabc'.rindex('def') == 3
    assert 'abcdefghiabc'.rindex('abc') == 9
    assert 'abcdefghiabc'.rindex('abc', 0, -1) == 0
    assert 'abcdefghiabc'.rindex('abc', -4*maxsize, 4*maxsize) == 9
    assert 'rrarrrrrrrrra'.rindex('a', 4, None) == 12
    assert u"\u1234\u5678".rindex(u'\u5678') == 1

    raises(ValueError, 'abcdefghiabc'.rindex, 'hib')
    raises(ValueError, 'defghiabc'.rindex, 'def', 1)
    raises(ValueError, 'defghiabc'.rindex, 'abc', 0, -1)
    raises(ValueError, 'abcdefghi'.rindex, 'ghi', 0, 8)
    raises(ValueError, 'abcdefghi'.rindex, 'ghi', 0, -1)
    raises(TypeError, 'abcdefghijklmn'.rindex, 'abc', 0, 0.0)
    raises(TypeError, 'abcdefghijklmn'.rindex, 'abc', -10.0, 30)

def test_rfind():
    assert 'abcdefghiabc'.rfind('abc') == 9
    assert 'abcdefghiabc'.rfind('') == 12
    assert 'abcdefghiabc'.rfind('abcd') == 0
    assert 'abcdefghiabc'.rfind('abcz') == -1
    assert u"\u1234\u5678".rfind(u'\u5678') == 1

def test_rfind_corner_case():
    assert 'abc'.rfind('', 4) == -1

def test_count_unicode():
    assert u'aaa'.count(u'', 10) == 0
    assert u'aaa'.count(u'', 3) == 1
    assert u"".count(u"x") ==0
    assert u"".count(u"") ==1
    assert u"Python".count(u"") ==7
    assert u"ab aaba".count(u"ab") ==2
    assert u'aaa'.count(u'a') == 3
    assert u'aaa'.count(u'b') == 0
    assert u'aaa'.count(u'a', -1) == 1
    assert u'aaa'.count(u'a', -10) == 3
    assert u'aaa'.count(u'a', 0, -1) == 2
    assert u'aaa'.count(u'a', 0, -10) == 0
    assert u'ababa'.count(u'aba') == 1

def test_swapcase():
    assert '\xe4\xc4\xdf'.swapcase() == '\xc4\xe4SS'
    # sigma-little becomes sigma-little-final
    assert u'A\u0345\u03a3'.swapcase() == u'a\u0399\u03c2'
    # but not if the previous codepoint is 0-width
    assert u'\u0345\u03a3'.swapcase() == u'\u0399\u03c3'

def test_call_special_methods():
    # xxx not completely clear if these are implementation details or not
    assert 'abc'.__add__('def') == 'abcdef'
    assert u'abc'.__rmod__(u'%s') == u'abc'
    ret = u'abc'.__rmod__('%s')
    with raises(AttributeError):
        u'abc'.__radd__(u'def')

def test_str_unicode_concat_overrides():
    "Test from Jython about being bug-compatible with CPython."

    def check(value, expected):
        assert type(value) == type(expected)
        assert value == expected

    def _test_concat(t1, t2):
        class SubclassB(t2):
            def __add__(self, other):
                return SubclassB(t2(self) + t2(other))
        check(SubclassB('py') + SubclassB('thon'), SubclassB('python'))
        check(t1('python') + SubclassB('3'), str('python3'))
        check(SubclassB('py') + t1('py'), SubclassB('pypy'))

        class SubclassC(t2):
            def __radd__(self, other):
                return SubclassC(t2(other) + t2(self))
        check(SubclassC('stack') + SubclassC('less'), t2('stackless'))
        check(t1('iron') + SubclassC('python'), SubclassC('ironpython'))
        check(SubclassC('tiny') + t1('py'), str('tinypy'))

        class SubclassD(t2):
            def __add__(self, other):
                return SubclassD(t2(self) + t2(other))

            def __radd__(self, other):
                return SubclassD(t2(other) + t2(self))
        check(SubclassD('di') + SubclassD('ct'), SubclassD('dict'))
        check(t1('list') + SubclassD(' comp'), SubclassD('list comp'))
        check(SubclassD('dun') + t1('der'), SubclassD('dunder'))

    _test_concat(str, str)

def test_returns_subclass1():
    class X(str):
        pass

    class Y(str):
        def __str__(self):
            return X("stuff")

    assert str(Y()).__class__ is X

def test_returns_subclass2():
    class StrSubclass(str):
        pass

    class WithRepr:
        def __init__(self, value):
            self.value = value
        def __repr__(self):
            return self.value

    expected = StrSubclass("abc")
    actual = ascii(WithRepr(expected))
    assert type(actual) is type(expected)
    assert actual == expected

    expected = r"<\U0001f40d>"
    actual = ascii(WithRepr(StrSubclass("<\U0001f40d>")))
    assert type(actual) is type(expected)
    assert actual == expected

def test_getslice():
    s = u"\u0105b\u0107"
    assert s[:] == u"\u0105b\u0107"
    assert s[1:] == u"b\u0107"
    assert s[:2] == u"\u0105b"
    assert s[1:2] == u"b"
    assert s[-2:] == u"b\u0107"
    assert s[:-1] == u"\u0105b"
    assert s[-2:2] == u"b"
    assert s[1:-1] == u"b"
    assert s[-2:-1] == u"b"

def test_getitem_slice():
    assert u'123456'.__getitem__(slice(1, 5)) == u'2345'
    s = u"\u0105b\u0107"
    assert s[slice(3)] == u"\u0105b\u0107"
    assert s[slice(1, 3)] == u"b\u0107"
    assert s[slice(2)] == u"\u0105b"
    assert s[slice(1, 2)] == u"b"
    assert s[slice(-2, 3)] == u"b\u0107"
    assert s[slice(-1)] == u"\u0105b"
    assert s[slice(-2, 2)] == u"b"
    assert s[slice(1, -1)] == u"b"
    assert s[slice(-2, -1)] == u"b"
    assert u"abcde"[::2] == u"ace"
    assert u"\u0105\u0106\u0107abcd"[::2] == u"\u0105\u0107bd"

def test_iter():
    foo = "\u1111\u2222\u3333"
    assert hasattr(foo, '__iter__')
    iter = foo.__iter__()
    assert next(iter) == '\u1111'
    assert next(iter) == '\u2222'

def test_no_len_on_str_iter():
    iterable = "hello"
    raises(TypeError, len, iter(iterable))

def test_encode_raw_unicode_escape():
    u = str(b'\\', 'raw_unicode_escape')
    assert u == '\\'
    s = '\u05d1\u05d3\u05d9\u05e7\u05d4'.encode('raw_unicode_escape')
    assert s == b'\\u05d1\\u05d3\\u05d9\\u05e7\\u05d4'

def test_decode_from_buffer():
    buf = b'character buffers are decoded to unicode'
    u = str(buf, 'utf-8', 'strict')
    assert u == 'character buffers are decoded to unicode'

def test_unicode_conversion_with__str__():
    class A(str):
        def __str__(self):
            return "foo"
    class B(str):
        pass
    a = A('bar')
    assert a == 'bar'
    assert str(a) == 'foo'
    b = B('bar')
    assert b == 'bar'
    assert str(b) == 'bar'

def test_unicode_conversion_with__str__():
    # new-style classes
    class A(object):
        def __str__(self):
            return '\u1234'
    s = str(A())
    assert type(s) is str
    assert s == '\u1234'
    # with old-style classes, it's different, but it should work as well
    class A:
        def __str__(self):
            return '\u1234'
    s = str(A())
    assert type(s) is str
    assert s == '\u1234'

def test_formatting_uchr():
    assert '%c' % '\U00021483' == '\U00021483'

def test_formatting_unicode__str__0():
    assert '%.2s' % "a\xe9\u20ac" == 'a\xe9'
    class A:
        def __init__(self, num):
            self.num = num
        def __str__(self):
            return chr(self.num)

    s = '%s' % A(111)    # this is ASCII
    assert type(s) is str
    assert s == chr(111)

    s = '%s' % A(0x1234)    # this is not ASCII
    assert type(s) is str
    assert s == '\u1234'

    # now the same with a new-style class...
    class A(object):
        def __init__(self, num):
            self.num = num
        def __str__(self):
            return chr(self.num)

    s = '%s' % A(111)    # this is ASCII
    assert type(s) is str
    assert s == chr(111)

    s = '%s' % A(0x1234)    # this is not ASCII
    assert type(s) is str
    assert s == '\u1234'

def test_formatting_unicode__str__2():
    class A:
        def __str__(self):
            return u'baz'

    class B:
        def __str__(self):
            return 'bar'

    a = A()
    b = B()
    s = '%s %s' % (a, b)
    assert s == 'baz bar'

def test_formatting_unicode__str__3():
    # "bah" is all I can say
    class X(object):
        def __repr__(self):
            return u'\u1234'
    '%s' % X()
    #
    class X(object):
        def __str__(self):
            return u'\u1234'
    '%s' % X()

def test_formatting_unicode__str__4():
    # from lib-python/3/test/test_tokenize
    fmt = "%(token)-13.13r %(start)s"
    vals = {"token" : u"Örter", "start": "(1, 0)"}
    expected = u"'Örter'       (1, 0)"
    s = fmt % vals
    assert s == expected, "\ns       = '%s'\nexpected= '%s'" %(s, expected)

def test_format_repeat():
    assert format(u"abc", u"z<5") == u"abczz"
    assert format(u"abc", u"\u2007<5") == u"abc\u2007\u2007"
    assert format(123, "\u2007<5") == "123\u2007\u2007"

def test_formatting_unicode__repr__():
    # Printable character
    assert '%r' % chr(0xe9) == "'\xe9'"

def test_formatting_not_tuple():
    class mydict(dict):
        pass
    assert 'xxx' % mydict() == 'xxx'
    assert 'xxx' % b'foo' == 'xxx'   # b'foo' considered as a mapping(!)
    assert 'xxx' % bytearray() == 'xxx'   # same
    assert 'xxx' % [] == 'xxx'       # [] considered as a mapping(!)
    with raises(TypeError):
        'xxx' % 'foo'
    with raises(TypeError):
        'xxx' % 53

def test_str_subclass():
    class Foo9(str):
        def __str__(self):
            return "world"
    assert str(Foo9("hello")) == "world"

def test_format_unicode_subclass():
    class U(str):
        def __str__(self):
            return '__str__ overridden'
    u = U('xxx')
    assert repr("%s" % u) == "'__str__ overridden'"
    assert repr("{}".format(u)) == "'__str__ overridden'"

def test_format_c_overflow():
    import sys
    raises(OverflowError, u'{0:c}'.format, -1)
    raises(OverflowError, u'{0:c}'.format, sys.maxunicode + 1)

def test_format_0s():
    assert "{0:8s}".format("result") == "result  "
    assert "{0:0s}".format("result") == "result"

def test_replace_with_buffer():
    raises(TypeError, 'abc'.replace, b'b', b'e')

def test_unicode_subclass():
    class S(str):
        pass

    a = S('hello \u1234')
    b = str(a)
    assert type(b) is str
    assert b == 'hello \u1234'

    assert '%s' % S('mar\xe7') == 'mar\xe7'

def test_format_new():
    assert '0{0}1{b}2'.format('A', b='B') == '0A1B2'

def test_format_map():
    assert '0{a}1'.format_map({'a': 'A'}) == '0A1'

def test_format_map_positional():
    raises(ValueError, '{}'.format_map, {})

def test_isdecimal():
    assert '0'.isdecimal()
    assert not ''.isdecimal()
    assert not 'a'.isdecimal()
    assert not '\u2460'.isdecimal() # CIRCLED DIGIT ONE

def test_isnumeric():
    assert '0'.isnumeric()
    assert not ''.isnumeric()
    assert not 'a'.isnumeric()
    assert '\u2460'.isnumeric() # CIRCLED DIGIT ONE

def test_replace_autoconvert():
    res = 'one!two!three!'.replace('!', '@', 1)
    assert res == 'one@two!three!'
    assert type(res) == str

def test_join_subclass():
    class StrSubclass(str):
        pass
    class BytesSubclass(bytes):
        pass

    s1 = StrSubclass('a')
    assert ''.join([s1]) is not s1
    s2 = BytesSubclass(b'a')
    assert b''.join([s2]) is not s2

def test_encoding_and_errors_cant_be_none():
    with raises(TypeError):
        b''.decode(None)
    with raises(TypeError):
        u''.encode(None)
    with raises(TypeError):
        str(b'', encoding=None)
    with raises(TypeError):
        u"".encode("utf-8", None)

def test_encode_wrong_errors():
    assert ''.encode(errors='some_wrong_name') == b''

def test_casefold():
    assert u'hello'.casefold() == u'hello'
    assert u'hELlo'.casefold() == u'hello'
    assert u'ß'.casefold() == u'ss'
    assert u'fi'.casefold() == u'fi'
    assert u'\u03a3'.casefold() == u'\u03c3'
    assert u'A\u0345\u03a3'.casefold() == u'a\u03b9\u03c3'
    assert u'\u00b5'.casefold() == u'\u03bc'

def test_lower_3a3():
    # Special case for GREEK CAPITAL LETTER SIGMA U+03A3
    assert u'\u03a3'.lower() == u'\u03c3'
    assert u'\u0345\u03a3'.lower() == u'\u0345\u03c3'
    assert u'A\u0345\u03a3'.lower() == u'a\u0345\u03c2'
    assert u'A\u0345\u03a3a'.lower() == u'a\u0345\u03c3a'
    assert u'A\u0345\u03a3'.lower() == u'a\u0345\u03c2'
    assert u'A\u03a3\u0345'.lower() == u'a\u03c2\u0345'
    assert u'\u03a3\u0345 '.lower() == u'\u03c3\u0345 '

def test_title_3a3():
    # Special case for GREEK CAPITAL LETTER SIGMA U+03A3
    assert u'\u03a3abc'.title() == u'\u03a3abc'
    assert u'\u03a3'.title() == u'Σ'
    assert u'\u0345\u03a3'.title() == u'Ισ'
    assert u'A\u0345\u03a3'.title() == u'Aͅς'
    assert u'A\u0345\u03a3a'.title() == u'Aͅσa'
    assert u'A\u0345\u03a3'.title() == u'Aͅς'
    assert u'A\u03a3\u0345'.title() == u'Aςͅ'
    assert u'\u03a3\u0345 '.title() == u'Σͅ '

    assert u'ääää \u03a3'.title() == u'Ääää Σ'
    assert u'ääää \u0345\u03a3'.title() == u'Ääää Ισ'
    assert u'ääää A\u0345\u03a3'.title() == u'Ääää Aͅς'
    assert u'ääää A\u0345\u03a3a'.title() == u'Ääää Aͅσa'
    assert u'ääää A\u0345\u03a3'.title() == u'Ääää Aͅς'
    assert u'ääää A\u03a3\u0345'.title() == u'Ääää Aςͅ'
    assert u'ääää \u03a3\u0345 '.title() == u'Ääää Σͅ '


def test_unicode_constructor_misc():
    x = u'foo'
    x += u'bar'
    assert str(x) is x
    #
    class U(str):
        def __str__(self):
            return u'BOK'
    u = U(x)
    assert str(u) == u'BOK'
    #
    class U2(str):
        pass
    z = U2(u'foobaz')
    assert type(str(z)) is str
    assert str(z) == u'foobaz'
    #
    assert str(encoding='supposedly_the_encoding') == u''
    assert str(errors='supposedly_the_error') == u''
    e = raises(TypeError, str, u'', 'supposedly_the_encoding')
    assert str(e.value) == 'decoding str is not supported'
    e = raises(TypeError, str, u'', errors='supposedly_the_error')
    assert str(e.value) == 'decoding str is not supported'
    e = raises(TypeError, str, u, 'supposedly_the_encoding')
    assert str(e.value) == 'decoding str is not supported'
    e = raises(TypeError, str, z, 'supposedly_the_encoding')
    assert str(e.value) == 'decoding str is not supported'
    #
    e = raises(TypeError, str, 42, 'supposedly_the_encoding')
    assert str(e.value) in [
        "decoding to str: a bytes-like object is required, not 'int'",
        'decoding to str: need a bytes-like object, int found']
    e = raises(TypeError, str, None, 'supposedly_the_encoding')
    assert str(e.value) in [
        'decoding to str: a bytes-like object is required, not None',
        'decoding to str: need a bytes-like object, NoneType found']

def test_reduce_iterator():
    it = iter(u"abcdef")
    assert next(it) == u"a"
    assert next(it) == u"b"
    assert next(it) == u"c"
    assert next(it) == u"d"
    args = it.__reduce__()
    assert next(it) == u"e"
    assert next(it) == u"f"
    it2 = args[0](*args[1])
    it2.__setstate__(args[2])
    assert next(it2) == u"e"
    assert next(it2) == u"f"
    it3 = args[0](*args[1])
    it3.__setstate__(args[2])
    assert next(it3) == u"e"
    assert next(it3) == u"f"


def test_newlist_utf8_non_ascii():
    'ä'.split("\n")[0] # does not crash

def test_replace_no_occurrence():
    x = u"xyz"
    assert x.replace(u"a", u"b") is x

def test_removeprefix():
    assert u'abc'.removeprefix(u'x') == u'abc'
    assert u'abc'.removeprefix(u'ab') == u'c'

def test_removesuffix():
    assert u'abc'.removesuffix(u'x') == u'abc'
    assert u'abc'.removesuffix(u'bc') == u'a'
    assert u'abc'.removesuffix(u'') == u'abc'
    assert u'spam'.removesuffix(u'am') == u'sp'

def test_id_preserved():
    a = u"abc"
    assert a * 1 is a

    class Sub(str):
        pass

    a = Sub(u"abc")
    assert a * 1 is not a

def test_bad_encoding():
    with raises(UnicodeEncodeError):
        u"abc".encode("utf-8\udce2\udc80\udc9d")

def test_mul():
    assert u'abc'.__mul__(2) == u'abcabc'
    with raises(TypeError):
        u'abc'.__mul__('')