from __future__ import with_statement
import py.test
import sys
from rpython.conftest import option

from rpython.annotator import model as annmodel
from rpython.annotator.annrpython import RPythonAnnotator as _RPythonAnnotator
from rpython.translator.translator import graphof as tgraphof
from rpython.annotator.policy import AnnotatorPolicy
from rpython.annotator.signature import Sig
from rpython.annotator.listdef import ListDef, ListChangeUnallowed
from rpython.annotator.dictdef import DictDef
from rpython.flowspace.model import *
from rpython.rlib.rarithmetic import r_uint, base_int, r_longlong, r_ulonglong
from rpython.rlib.rarithmetic import r_singlefloat
from rpython.rlib import objectmodel
from rpython.flowspace.flowcontext import FlowingError
from rpython.flowspace.operation import op

from rpython.translator.test import snippet

def graphof(a, func):
    return tgraphof(a.translator, func)

def listitem(s_list):
    assert isinstance(s_list, annmodel.SomeList)
    return s_list.listdef.listitem.s_value

def somelist(s_type):
    return annmodel.SomeList(ListDef(None, s_type))

def dictkey(s_dict):
    assert isinstance(s_dict, annmodel.SomeDict)
    return s_dict.dictdef.dictkey.s_value

def dictvalue(s_dict):
    assert isinstance(s_dict, annmodel.SomeDict)
    return s_dict.dictdef.dictvalue.s_value

def somedict(s_key, s_value):
    return annmodel.SomeDict(DictDef(None, s_key, s_value))


class TestAnnotateTestCase:
    def teardown_method(self, meth):
        assert annmodel.s_Bool == annmodel.SomeBool()

    class RPythonAnnotator(_RPythonAnnotator):
        def build_types(self, *args):
            s = _RPythonAnnotator.build_types(self, *args)
            self.validate()
            if option.view:
                self.translator.view()
            return s

    def test_simple_func(self):
        """
        one test source:
        def f(x):
            return x+1
        """
        x = Variable("x")
        oper = op.add(x, Constant(1))
        block = Block([x])
        fun = FunctionGraph("f", block)
        block.operations.append(oper)
        block.closeblock(Link([oper.result], fun.returnblock))
        a = self.RPythonAnnotator()
        a.addpendingblock(fun, fun.startblock, [annmodel.SomeInteger()])
        a.complete()
        assert a.gettype(fun.getreturnvar()) == int

    def test_while(self):
        """
        one test source:
        def f(i):
            while i > 0:
                i = i - 1
            return i
        """
        i1 = Variable("i1")
        i2 = Variable("i2")
        conditionop = op.gt(i1, Constant(0))
        decop = op.add(i2, Constant(-1))
        headerblock = Block([i1])
        whileblock = Block([i2])

        fun = FunctionGraph("f", headerblock)
        headerblock.operations.append(conditionop)
        headerblock.exitswitch = conditionop.result
        headerblock.closeblock(Link([i1], fun.returnblock, False),
                               Link([i1], whileblock, True))
        whileblock.operations.append(decop)
        whileblock.closeblock(Link([decop.result], headerblock))

        a = self.RPythonAnnotator()
        a.addpendingblock(fun, fun.startblock, [annmodel.SomeInteger()])
        a.complete()
        assert a.gettype(fun.getreturnvar()) == int

    def test_while_sum(self):
        """
        one test source:
        def f(i):
            sum = 0
            while i > 0:
                sum = sum + i
                i = i - 1
            return sum
        """
        i1 = Variable("i1")
        i2 = Variable("i2")
        i3 = Variable("i3")
        sum2 = Variable("sum2")
        sum3 = Variable("sum3")

        conditionop = op.gt(i2, Constant(0))
        decop = op.add(i3, Constant(-1))
        addop = op.add(i3, sum3)
        startblock = Block([i1])
        headerblock = Block([i2, sum2])
        whileblock = Block([i3, sum3])

        fun = FunctionGraph("f", startblock)
        startblock.closeblock(Link([i1, Constant(0)], headerblock))
        headerblock.operations.append(conditionop)
        headerblock.exitswitch = conditionop.result
        headerblock.closeblock(Link([sum2], fun.returnblock, False),
                               Link([i2, sum2], whileblock, True))
        whileblock.operations.append(addop)
        whileblock.operations.append(decop)
        whileblock.closeblock(Link([decop.result, addop.result], headerblock))

        a = self.RPythonAnnotator()
        a.addpendingblock(fun, fun.startblock, [annmodel.SomeInteger()])
        a.complete()
        assert a.gettype(fun.getreturnvar()) == int

    def test_f_calls_g(self):
        a = self.RPythonAnnotator()
        s = a.build_types(f_calls_g, [int])
        # result should be an integer
        assert s.knowntype == int

    def test_lists(self):
        a = self.RPythonAnnotator()
        end_cell = a.build_types(snippet.poor_man_rev_range, [int])
        # result should be a list of integers
        assert listitem(end_cell).knowntype == int

    def test_factorial(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.factorial, [int])
        # result should be an integer
        assert s.knowntype == int

    def test_factorial2(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.factorial2, [int])
        # result should be an integer
        assert s.knowntype == int

    def test_build_instance(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.build_instance, [])
        # result should be a snippet.C instance
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef == a.bookkeeper.getuniqueclassdef(snippet.C)

    def test_set_attr(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.set_attr, [])
        # result should be an integer
        assert s.knowntype == int

    def test_merge_setattr(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.merge_setattr, [int])
        # result should be an integer
        assert s.knowntype == int

    def test_inheritance1(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.inheritance1, [])
        # result should be exactly:
        assert s == annmodel.SomeTuple([
                                a.bookkeeper.immutablevalue(()),
                                annmodel.SomeInteger()
                                ])

    def test_poor_man_range(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.poor_man_range, [int])
        # result should be a list of integers
        assert listitem(s).knowntype == int

    def test_staticmethod(self):
        class X(object):
            @staticmethod
            def stat(value):
                return value + 4
        def f(v):
            return X().stat(v)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeInteger)

    def test_classmethod(self):
        class X(object):
            @classmethod
            def meth(cls):
                return None
        def f():
            return X().meth()
        a = self.RPythonAnnotator()
        py.test.raises(annmodel.AnnotatorError, a.build_types, f,  [])

    def test_methodcall1(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet._methodcall1, [int])
        # result should be a tuple of (C, positive_int)
        assert s.knowntype == tuple
        assert len(s.items) == 2
        s0 = s.items[0]
        assert isinstance(s0, annmodel.SomeInstance)
        assert s0.classdef == a.bookkeeper.getuniqueclassdef(snippet.C)
        assert s.items[1].knowntype == int
        assert s.items[1].nonneg == True

    def test_classes_methodcall1(self):
        a = self.RPythonAnnotator()
        a.build_types(snippet._methodcall1, [int])
        # the user classes should have the following attributes:
        getcdef = a.bookkeeper.getuniqueclassdef
        assert getcdef(snippet.F).attrs.keys() == ['m']
        assert getcdef(snippet.G).attrs.keys() == ['m2']
        assert getcdef(snippet.H).attrs.keys() == ['attr']
        assert getcdef(snippet.H).about_attribute('attr') == (
                          a.bookkeeper.immutablevalue(1))

    def test_generaldict(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.generaldict, [str, int, str, int])
        # result should be an integer
        assert s.knowntype == int

    def test_somebug1(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet._somebug1, [int])
        # result should be a built-in method
        assert isinstance(s, annmodel.SomeBuiltin)

    def test_with_init(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.with_init, [int])
        # result should be an integer
        assert s.knowntype == int

    def test_with_more_init(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.with_more_init, [int, bool])
        # the user classes should have the following attributes:
        getcdef = a.bookkeeper.getuniqueclassdef
        # XXX on which class should the attribute 'a' appear?  We only
        #     ever flow WithInit.__init__ with a self which is an instance
        #     of WithMoreInit, so currently it appears on WithMoreInit.
        assert getcdef(snippet.WithMoreInit).about_attribute('a') == (
                          annmodel.SomeInteger())
        assert getcdef(snippet.WithMoreInit).about_attribute('b') == (
                          annmodel.SomeBool())

    def test_global_instance(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.global_instance, [])
        # currently this returns the constant 42.
        # XXX not sure this is the best behavior...
        assert s == a.bookkeeper.immutablevalue(42)

    def test_call_five(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.call_five, [])
        # returns should be a list of constants (= 5)
        assert listitem(s) == a.bookkeeper.immutablevalue(5)

    def test_call_five_six(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.call_five_six, [])
        # returns should be a list of positive integers
        assert listitem(s) == annmodel.SomeInteger(nonneg=True)

    def test_constant_result(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.constant_result, [])
        #a.translator.simplify()
        # must return "yadda"
        assert s == a.bookkeeper.immutablevalue("yadda")
        graphs = a.translator.graphs
        assert len(graphs) == 2
        assert graphs[0].func is snippet.constant_result
        assert graphs[1].func is snippet.forty_two
        a.simplify()
        #a.translator.view()

    def test_flow_type_info(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.flow_type_info, [int])
        a.simplify()
        assert s.knowntype == int

        a = self.RPythonAnnotator()
        s = a.build_types(snippet.flow_type_info, [str])
        a.simplify()
        assert s.knowntype == int

    def test_flow_type_info_2(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.flow_type_info,
                          [annmodel.SomeInteger(nonneg=True)])
        # this checks that isinstance(i, int) didn't lose the
        # actually more precise information that i is non-negative
        assert s == annmodel.SomeInteger(nonneg=True)

    def test_flow_usertype_info(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.flow_usertype_info, [snippet.WithInit])
        #a.translator.view()
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef == a.bookkeeper.getuniqueclassdef(snippet.WithInit)

    def test_flow_usertype_info2(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.flow_usertype_info, [snippet.WithMoreInit])
        #a.translator.view()
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef == a.bookkeeper.getuniqueclassdef(snippet.WithMoreInit)

    def test_mergefunctions(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.mergefunctions, [int])
        # the test is mostly that the above line hasn't blown up
        # but let's at least check *something*
        assert isinstance(s, annmodel.SomePBC)

    def test_func_calls_func_which_just_raises(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.funccallsex, [])
        # the test is mostly that the above line hasn't blown up
        # but let's at least check *something*
        #self.assert_(isinstance(s, SomeCallable))

    def test_tuple_unpack_from_const_tuple_with_different_types(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.func_arg_unpack, [])
        assert isinstance(s, annmodel.SomeInteger)
        assert s.const == 3

    def test_pbc_attr_preserved_on_instance(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.preserve_pbc_attr_on_instance, [bool])
        #a.simplify()
        #a.translator.view()
        assert s == annmodel.SomeInteger(nonneg=True)
        #self.assertEquals(s.__class__, annmodel.SomeInteger)

    def test_pbc_attr_preserved_on_instance_with_slots(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.preserve_pbc_attr_on_instance_with_slots,
                          [bool])
        assert s == annmodel.SomeInteger(nonneg=True)

    def test_is_and_knowntype_data(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.is_and_knowntype, [str])
        #a.simplify()
        #a.translator.view()
        assert s == a.bookkeeper.immutablevalue(None)

    def test_isinstance_and_knowntype_data(self):
        a = self.RPythonAnnotator()
        x = a.bookkeeper.immutablevalue(snippet.apbc)
        s = a.build_types(snippet.isinstance_and_knowntype, [x])
        #a.simplify()
        #a.translator.view()
        assert s == x

    def test_somepbc_simplify(self):
        a = self.RPythonAnnotator()
        # this example used to trigger an AssertionError
        a.build_types(snippet.somepbc_simplify, [])

    def test_builtin_methods(self):
        a = self.RPythonAnnotator()
        iv = a.bookkeeper.immutablevalue
        # this checks that some built-in methods are really supported by
        # the annotator (it doesn't check that they operate property, though)
        for example, methname, s_example in [
            ('', 'join',    annmodel.SomeString()),
            ([], 'append',  somelist(annmodel.s_Int)),
            ([], 'extend',  somelist(annmodel.s_Int)),
            ([], 'reverse', somelist(annmodel.s_Int)),
            ([], 'insert',  somelist(annmodel.s_Int)),
            ([], 'pop',     somelist(annmodel.s_Int)),
            ]:
            constmeth = getattr(example, methname)
            s_constmeth = iv(constmeth)
            assert isinstance(s_constmeth, annmodel.SomeBuiltin)
            s_meth = s_example.getattr(iv(methname))
            assert isinstance(s_constmeth, annmodel.SomeBuiltin)

    def test_str_join(self):
        a = self.RPythonAnnotator()
        def g(n):
            if n:
                return ["foo", "bar"]
        def f(n):
            g(0)
            return ''.join(g(n))
        s = a.build_types(f, [int])
        assert s.knowntype == str
        assert s.no_nul

    def test_str_split(self):
        a = self.RPythonAnnotator()
        def g(n):
            if n:
                return "test string"
        def f(n):
            if n:
                return g(n).split(' ')
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeList)
        s_item = s.listdef.listitem.s_value
        assert s_item.no_nul

    def test_str_split_nul(self):
        def f(n):
            return n.split('\0')[0]
        a = self.RPythonAnnotator()
        a.translator.config.translation.check_str_without_nul = True
        s = a.build_types(f, [annmodel.SomeString(no_nul=False, can_be_None=False)])
        assert isinstance(s, annmodel.SomeString)
        assert not s.can_be_None
        assert s.no_nul

        def g(n):
            return n.split('\0', 1)[0]
        a = self.RPythonAnnotator()
        a.translator.config.translation.check_str_without_nul = True
        s = a.build_types(g, [annmodel.SomeString(no_nul=False, can_be_None=False)])
        assert isinstance(s, annmodel.SomeString)
        assert not s.can_be_None
        assert not s.no_nul

    def test_str_splitlines(self):
        a = self.RPythonAnnotator()
        def f(a_str):
            return a_str.splitlines()
        s = a.build_types(f, [str])
        assert isinstance(s, annmodel.SomeList)
        assert s.listdef.listitem.resized

    def test_str_strip(self):
        a = self.RPythonAnnotator()
        def f(n, a_str):
            if n == 0:
                return a_str.strip(' ')
            elif n == 1:
                return a_str.rstrip(' ')
            else:
                return a_str.lstrip(' ')
        s = a.build_types(f, [int, annmodel.SomeString(no_nul=True)])
        assert s.no_nul

    def test_str_mul(self):
        a = self.RPythonAnnotator()
        def f(a_str):
            return a_str * 3
        s = a.build_types(f, [str])
        assert isinstance(s, annmodel.SomeString)

    def test_str_isalpha(self):
        def f(s):
            return s.isalpha()
        a = self.RPythonAnnotator()
        s = a.build_types(f, [str])
        assert isinstance(s, annmodel.SomeBool)

    def test_simple_slicing(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.simple_slice, [somelist(annmodel.s_Int)])
        assert isinstance(s, annmodel.SomeList)

    def test_simple_iter_list(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.simple_iter, [somelist(annmodel.s_Int)])
        assert isinstance(s, annmodel.SomeIterator)

    def test_simple_iter_next(self):
        def f(x):
            i = iter(range(x))
            return i.next()
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeInteger)

    def test_simple_iter_dict(self):
        a = self.RPythonAnnotator()
        t = somedict(annmodel.SomeInteger(), annmodel.SomeInteger())
        s = a.build_types(snippet.simple_iter, [t])
        assert isinstance(s, annmodel.SomeIterator)

    def test_simple_zip(self):
        a = self.RPythonAnnotator()
        x = somelist(annmodel.SomeInteger())
        y = somelist(annmodel.SomeString())
        s = a.build_types(snippet.simple_zip, [x,y])
        assert s.knowntype == list
        assert listitem(s).knowntype == tuple
        assert listitem(s).items[0].knowntype == int
        assert listitem(s).items[1].knowntype == str

    def test_dict_copy(self):
        a = self.RPythonAnnotator()
        t = somedict(annmodel.SomeInteger(), annmodel.SomeInteger())
        s = a.build_types(snippet.dict_copy, [t])
        assert isinstance(dictkey(s), annmodel.SomeInteger)
        assert isinstance(dictvalue(s), annmodel.SomeInteger)

    def test_dict_update(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.dict_update, [int])
        assert isinstance(dictkey(s), annmodel.SomeInteger)
        assert isinstance(dictvalue(s), annmodel.SomeInteger)

    def test_dict_update_2(self):
        a = self.RPythonAnnotator()
        def g(n):
            if n:
                return {3: 4}
        def f(n):
            g(0)
            d = {}
            d.update(g(n))
            return d
        s = a.build_types(f, [int])
        assert dictkey(s).knowntype == int

    def test_dict_keys(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.dict_keys, [])
        assert isinstance(listitem(s), annmodel.SomeString)

    def test_dict_keys2(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.dict_keys2, [])
        assert type(listitem(s)) is annmodel.SomeString

    def test_dict_values(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.dict_values, [])
        assert isinstance(listitem(s), annmodel.SomeString)

    def test_dict_values2(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.dict_values2, [])
        assert type(listitem(s)) is annmodel.SomeString

    def test_dict_items(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.dict_items, [])
        assert isinstance(listitem(s), annmodel.SomeTuple)
        s_key, s_value = listitem(s).items
        assert isinstance(s_key, annmodel.SomeString)
        assert isinstance(s_value, annmodel.SomeInteger)

    def test_dict_setdefault(self):
        a = self.RPythonAnnotator()
        def f():
            d = {}
            d.setdefault('a', 2)
            d.setdefault('a', -3)
            return d
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeDict)
        assert isinstance(dictkey(s), annmodel.SomeString)
        assert isinstance(dictvalue(s), annmodel.SomeInteger)
        assert not dictvalue(s).nonneg

    def test_exception_deduction(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.exception_deduction, [])
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef is a.bookkeeper.getuniqueclassdef(snippet.Exc)

    def test_exception_deduction_we_are_dumb(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.exception_deduction_we_are_dumb, [])
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef is a.bookkeeper.getuniqueclassdef(snippet.Exc)

    def test_nested_exception_deduction(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.nested_exception_deduction, [])
        assert isinstance(s, annmodel.SomeTuple)
        assert isinstance(s.items[0], annmodel.SomeInstance)
        assert isinstance(s.items[1], annmodel.SomeInstance)
        assert s.items[0].classdef is a.bookkeeper.getuniqueclassdef(snippet.Exc)
        assert s.items[1].classdef is a.bookkeeper.getuniqueclassdef(snippet.Exc2)

    def test_exc_deduction_our_exc_plus_others(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.exc_deduction_our_exc_plus_others, [])
        assert isinstance(s, annmodel.SomeInteger)

    def test_exc_deduction_our_excs_plus_others(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.exc_deduction_our_excs_plus_others, [])
        assert isinstance(s, annmodel.SomeInteger)

    def test_operation_always_raising(self):
        def operation_always_raising(n):
            lst = []
            try:
                return lst[n]
            except IndexError:
                return 24
        a = self.RPythonAnnotator()
        s = a.build_types(operation_always_raising, [int])
        assert s == a.bookkeeper.immutablevalue(24)

    def test_propagation_of_fresh_instances_through_attrs(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.propagation_of_fresh_instances_through_attrs, [int])
        assert s is not None

    def test_propagation_of_fresh_instances_through_attrs_rec_0(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.make_r, [int])
        Rdef = a.bookkeeper.getuniqueclassdef(snippet.R)
        assert s.classdef == Rdef
        assert Rdef.attrs['r'].s_value.classdef == Rdef
        assert Rdef.attrs['n'].s_value.knowntype == int
        assert Rdef.attrs['m'].s_value.knowntype == int


    def test_propagation_of_fresh_instances_through_attrs_rec_eo(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.make_eo, [int])
        assert s.classdef == a.bookkeeper.getuniqueclassdef(snippet.B)
        Even_def = a.bookkeeper.getuniqueclassdef(snippet.Even)
        Odd_def = a.bookkeeper.getuniqueclassdef(snippet.Odd)
        assert listitem(Even_def.attrs['x'].s_value).classdef == Odd_def
        assert listitem(Even_def.attrs['y'].s_value).classdef == Even_def
        assert listitem(Odd_def.attrs['x'].s_value).classdef == Even_def
        assert listitem(Odd_def.attrs['y'].s_value).classdef == Odd_def

    def test_flow_rev_numbers(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.flow_rev_numbers, [int])
        assert s.knowntype == int
        assert not s.is_constant() # !

    def test_methodcall_is_precise(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.methodcall_is_precise, [bool])
        getcdef = a.bookkeeper.getuniqueclassdef
        assert 'x' not in getcdef(snippet.CBase).attrs
        assert (getcdef(snippet.CSub1).attrs['x'].s_value ==
                a.bookkeeper.immutablevalue(42))
        assert (getcdef(snippet.CSub2).attrs['x'].s_value ==
                a.bookkeeper.immutablevalue('world'))
        assert s == a.bookkeeper.immutablevalue(42)

    def test_call_star_args(self):
        a = self.RPythonAnnotator(policy=AnnotatorPolicy())
        s = a.build_types(snippet.call_star_args, [int])
        assert s.knowntype == int

    def test_call_star_args_multiple(self):
        a = self.RPythonAnnotator(policy=AnnotatorPolicy())
        s = a.build_types(snippet.call_star_args_multiple, [int])
        assert s.knowntype == int

    def test_class_spec(self):
        a = self.RPythonAnnotator(policy=AnnotatorPolicy())
        s = a.build_types(snippet.class_spec, [])
        assert s.items[0].knowntype == int
        assert s.items[1].knowntype == str

    def test_class_spec_confused(self):
        x = snippet.PolyStk()
        def f():
            return x
        a = self.RPythonAnnotator(policy=AnnotatorPolicy())
        py.test.raises(Exception, a.build_types, f, [])

    def test_exception_deduction_with_raise1(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.exception_deduction_with_raise1, [bool])
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef is a.bookkeeper.getuniqueclassdef(snippet.Exc)


    def test_exception_deduction_with_raise2(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.exception_deduction_with_raise2, [bool])
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef is a.bookkeeper.getuniqueclassdef(snippet.Exc)

    def test_exception_deduction_with_raise3(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.exception_deduction_with_raise3, [bool])
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef is a.bookkeeper.getuniqueclassdef(snippet.Exc)

    def test_type_is(self):
        class B(object):
            pass
        class C(B):
            pass
        def f(x):
            assert type(x) is C
            return x
        a = self.RPythonAnnotator()
        s = a.build_types(f, [B])
        assert s.classdef is a.bookkeeper.getuniqueclassdef(C)

    def test_union_type_some_pbc(self):
        py.test.skip("is there a point? f() can return self.__class__ instead")
        class A(object):
            name = "A"

            def f(self):
                return type(self)

        class B(A):
            name = "B"

        def f(tp):
            return tp

        def main(n):
            if n:
                if n == 1:
                    inst = A()
                else:
                    inst = B()
                arg = inst.f()
            else:
                arg = B
            return f(arg).name

        a = self.RPythonAnnotator()
        s = a.build_types(main, [int])
        assert isinstance(s, annmodel.SomeString)

    def test_ann_assert(self):
        def assert_(x):
            assert x,"XXX"
        a = self.RPythonAnnotator()
        s = a.build_types(assert_, [int])
        assert s.const is None

    def test_string_and_none(self):
        def f(n):
            if n:
                return 'y'
            else:
                return 'n'
        def g(n):
            if n:
                return 'y'
            else:
                return None
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])
        assert s.knowntype == str
        assert not s.can_be_None
        s = a.build_types(g, [bool])
        assert s.knowntype == str
        assert s.can_be_None

    def test_implicit_exc(self):
        def f(l):
            try:
                l[0]
            except (KeyError, IndexError),e:
                return e
            return None

        a = self.RPythonAnnotator()
        s = a.build_types(f, [somelist(annmodel.s_Int)])
        assert s.classdef is a.bookkeeper.getuniqueclassdef(IndexError)  # KeyError ignored because l is a list

    def test_freeze_protocol(self):
        class Stuff:
            def __init__(self):
                self.called = False
            def _freeze_(self):
                self.called = True
                return True
        myobj = Stuff()
        a = self.RPythonAnnotator()
        s = a.build_types(lambda: myobj, [])
        assert myobj.called
        assert isinstance(s, annmodel.SomePBC)
        assert s.const == myobj

    def test_cleanup_protocol(self):
        class Stuff:
            def __init__(self):
                self.called = False
            def _cleanup_(self):
                self.called = True
        myobj = Stuff()
        a = self.RPythonAnnotator()
        s = a.build_types(lambda: myobj, [])
        assert myobj.called
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef is a.bookkeeper.getuniqueclassdef(Stuff)

    def test_circular_mutable_getattr(self):
        class C:
            pass
        c = C()
        c.x = c
        def f():
            return c.x
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef == a.bookkeeper.getuniqueclassdef(C)

    def test_circular_list_type(self):
        def f(n):
            lst = []
            for i in range(n):
                lst = [lst]
            return lst
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert listitem(s) == s

    def test_harmonic(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.harmonic, [int])
        assert s.knowntype == float
        # check that the list produced by range() is not mutated or resized
        graph = graphof(a, snippet.harmonic)
        all_vars = set().union(*[block.getvariables() for block in graph.iterblocks()])
        print all_vars
        for var in all_vars:
            s_value = var.annotation
            if isinstance(s_value, annmodel.SomeList):
                assert not s_value.listdef.listitem.resized
                assert not s_value.listdef.listitem.mutated
                assert s_value.listdef.listitem.range_step

    def test_bool(self):
        def f(a,b):
            return bool(a) or bool(b)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int, somelist(annmodel.s_Int)])
        assert s.knowntype == bool

    def test_float(self):
        def f(n):
            return float(n)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.knowntype == float

    def test_r_uint(self):
        def f(n):
            return n + constant_unsigned_five
        a = self.RPythonAnnotator()
        s = a.build_types(f, [r_uint])
        assert s == annmodel.SomeInteger(nonneg = True, unsigned = True)

    def test_large_unsigned(self):
        large_constant = sys.maxint * 2 + 1 # 0xFFFFFFFF on 32-bit platforms
        def f():
            return large_constant
        a = self.RPythonAnnotator()
        py.test.raises(Exception, a.build_types, f, [])
        # if you want to get a r_uint, you have to be explicit about it

    def test_add_different_ints(self):
        def f(a, b):
            return a + b
        a = self.RPythonAnnotator()
        py.test.raises(Exception, a.build_types, f, [r_uint, int])

    def test_merge_different_ints(self):
        def f(a, b):
            if a:
                c = a
            else:
                c = b
            return c
        a = self.RPythonAnnotator()
        py.test.raises(Exception, a.build_types, f, [r_uint, int])

    def test_merge_ruint_zero(self):
        def f(a):
            if a:
                c = a
            else:
                c = 0
            return c
        a = self.RPythonAnnotator()
        s = a.build_types(f, [r_uint])
        assert s == annmodel.SomeInteger(nonneg = True, unsigned = True)

    def test_merge_ruint_nonneg_signed(self):
        def f(a, b):
            if a:
                c = a
            else:
                assert b >= 0
                c = b
            return c
        a = self.RPythonAnnotator()
        s = a.build_types(f, [r_uint, int])
        assert s == annmodel.SomeInteger(nonneg = True, unsigned = True)


    def test_prebuilt_long_that_is_not_too_long(self):
        small_constant = 12L
        def f():
            return small_constant
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.const == 12
        assert s.nonneg
        assert not s.unsigned
        #
        small_constant = -23L
        def f():
            return small_constant
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.const == -23
        assert not s.nonneg
        assert not s.unsigned

    def test_pbc_getattr(self):
        class C:
            def __init__(self, v1, v2):
                self.v2 = v2
                self.v1 = v1

            def _freeze_(self):
                return True

        c1 = C(1,'a')
        c2 = C(2,'b')
        c3 = C(3,'c')

        def f1(l, c):
            l.append(c.v1)
        def f2(l, c):
            l.append(c.v2)

        def g():
            l1 = []
            l2 = []
            f1(l1, c1)
            f1(l1, c2)
            f2(l2, c2)
            f2(l2, c3)
            return l1,l2

        a = self.RPythonAnnotator()
        s = a.build_types(g,[])
        l1, l2 = s.items
        assert listitem(l1).knowntype == int
        assert listitem(l2).knowntype == str


        acc1 = a.bookkeeper.getdesc(c1).getattrfamily()
        acc2 = a.bookkeeper.getdesc(c2).getattrfamily()
        acc3 = a.bookkeeper.getdesc(c3).getattrfamily()

        assert acc1 is acc2 is acc3

        assert len(acc1.descs) == 3
        assert dict.fromkeys(acc1.attrs) == {'v1': None, 'v2': None}

    def test_single_pbc_getattr(self):
        class C:
            def __init__(self, v1, v2):
                self.v1 = v1
                self.v2 = v2
            def _freeze_(self):
                return True
        c1 = C(11, "hello")
        c2 = C(22, 623)
        def f1(l, c):
            l.append(c.v1)
        def f2(c):
            return c.v2
        def f3(c):
            return c.v2
        def g():
            l = []
            f1(l, c1)
            f1(l, c2)
            return l, f2(c1), f3(c2)

        a = self.RPythonAnnotator()
        s = a.build_types(g,[])
        s_l, s_c1v2, s_c2v2 = s.items
        assert listitem(s_l).knowntype == int
        assert s_c1v2.const == "hello"
        assert s_c2v2.const == 623

        acc1 = a.bookkeeper.getdesc(c1).getattrfamily()
        acc2 = a.bookkeeper.getdesc(c2).getattrfamily()
        assert acc1 is acc2
        assert acc1.attrs.keys() == ['v1']

    def test_simple_pbc_call(self):
        def f1(x,y=0):
            pass
        def f2(x):
            pass
        def f3(x):
            pass
        def g(f):
            f(1)
        def h():
            f1(1)
            f1(1,2)
            g(f2)
            g(f3)

        a = self.RPythonAnnotator()
        s = a.build_types(h, [])

        fdesc1 = a.bookkeeper.getdesc(f1)
        fdesc2 = a.bookkeeper.getdesc(f2)
        fdesc3 = a.bookkeeper.getdesc(f3)

        fam1 = fdesc1.getcallfamily()
        fam2 = fdesc2.getcallfamily()
        fam3 = fdesc3.getcallfamily()

        assert fam1 is not fam2
        assert fam1 is not fam3
        assert fam3 is fam2

        gf1 = graphof(a, f1)
        gf2 = graphof(a, f2)
        gf3 = graphof(a, f3)

        assert fam1.calltables == {(2, (), False): [{fdesc1: gf1}],
                                   (1, (), False): [{fdesc1: gf1}]}
        assert fam2.calltables == {(1, (), False): [{fdesc2: gf2, fdesc3: gf3}]}

    def test_pbc_call_ins(self):
        class A(object):
            def m(self):
                pass
        class B(A):
            def n(self):
                pass
        class C(A):
            def __init__(self):
                pass
            def m(self):
                pass
        def f(x):
            b = B()
            c = C()
            b.n()
            if x:
                a = b
            else:
                a = c
            a.m()

        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])

        clsdef = a.bookkeeper.getuniqueclassdef
        bookkeeper = a.bookkeeper

        def getmdesc(bmeth):
            return bookkeeper.immutablevalue(bmeth).any_description()

        mdescA_m = getmdesc(A().m)
        mdescC_m = getmdesc(C().m)
        mdescB_n = getmdesc(B().n)

        assert mdescA_m.name == 'm' == mdescC_m.name
        assert mdescB_n.name == 'n'

        famA_m = mdescA_m.getcallfamily()
        famC_m = mdescC_m.getcallfamily()
        famB_n = mdescB_n.getcallfamily()

        assert famA_m is famC_m
        assert famB_n is not famA_m

        gfB_n = graphof(a, B.n.im_func)
        gfA_m = graphof(a, A.m.im_func)
        gfC_m = graphof(a, C.m.im_func)

        assert famB_n.calltables == {(1, (), False): [{mdescB_n.funcdesc: gfB_n}] }
        assert famA_m.calltables == {(1, (), False): [{mdescA_m.funcdesc: gfA_m, mdescC_m.funcdesc: gfC_m }] }

        mdescCinit = getmdesc(C().__init__)
        famCinit = mdescCinit.getcallfamily()
        gfCinit = graphof(a, C.__init__.im_func)

        assert famCinit.calltables == {(1, (), False): [{mdescCinit.funcdesc: gfCinit}] }

    def test_isinstance_usigned(self):
        def f(x):
            return isinstance(x, r_uint)
        def g():
            v = r_uint(1)
            return f(v)
        a = self.RPythonAnnotator()
        s = a.build_types(g, [])
        assert s.const == True

    def test_isinstance_base_int(self):
        def f(x):
            return isinstance(x, base_int)
        def g(n):
            v = r_uint(n)
            return f(v)
        a = self.RPythonAnnotator()
        s = a.build_types(g, [int])
        assert s.const == True

    def test_alloc_like(self):
        class Base(object):
            pass
        class C1(Base):
            pass
        class C2(Base):
            pass

        def inst(cls):
            return cls()

        def alloc(cls):
            i = inst(cls)
            assert isinstance(i, cls)
            return i
        alloc._annspecialcase_ = "specialize:arg(0)"

        def f():
            c1 = alloc(C1)
            c2 = alloc(C2)
            return c1,c2

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        C1df = a.bookkeeper.getuniqueclassdef(C1)
        C2df = a.bookkeeper.getuniqueclassdef(C2)

        assert s.items[0].classdef == C1df
        assert s.items[1].classdef == C2df

        allocdesc = a.bookkeeper.getdesc(alloc)
        s_C1 = a.bookkeeper.immutablevalue(C1)
        s_C2 = a.bookkeeper.immutablevalue(C2)
        graph1 = allocdesc.specialize([s_C1], None)
        graph2 = allocdesc.specialize([s_C2], None)
        assert a.binding(graph1.getreturnvar()).classdef == C1df
        assert a.binding(graph2.getreturnvar()).classdef == C2df
        assert graph1 in a.translator.graphs
        assert graph2 in a.translator.graphs

    def test_specialcase_args(self):
        class C1(object):
            pass

        class C2(object):
            pass

        def alloc(cls, cls2):
            i = cls()
            assert isinstance(i, cls)
            j = cls2()
            assert isinstance(j, cls2)
            return i

        def f():
            alloc(C1, C1)
            alloc(C1, C2)
            alloc(C2, C1)
            alloc(C2, C2)

        alloc._annspecialcase_ = "specialize:arg(0,1)"

        a = self.RPythonAnnotator()
        C1df = a.bookkeeper.getuniqueclassdef(C1)
        C2df = a.bookkeeper.getuniqueclassdef(C2)
        s = a.build_types(f, [])
        allocdesc = a.bookkeeper.getdesc(alloc)
        s_C1 = a.bookkeeper.immutablevalue(C1)
        s_C2 = a.bookkeeper.immutablevalue(C2)
        graph1 = allocdesc.specialize([s_C1, s_C2], None)
        graph2 = allocdesc.specialize([s_C2, s_C2], None)
        assert a.binding(graph1.getreturnvar()).classdef == C1df
        assert a.binding(graph2.getreturnvar()).classdef == C2df
        assert graph1 in a.translator.graphs
        assert graph2 in a.translator.graphs

    def test_specialize_arg_bound_method(self):
        class GC(object):
            def trace(self, callback, *args):
                return callback(*args)
            trace._annspecialcase_ = "specialize:arg(1)"

            def callback1(self, arg1):
                self.x = arg1
                return "hello"

            def callback2(self, arg2, arg3):
                self.y = arg2
                self.z = arg3
                return 6

        def f():
            gc = GC()
            s1 = gc.trace(gc.callback1, "foo")
            n2 = gc.trace(gc.callback2, 7, 2)
            return (s1, n2, gc.x, gc.y, gc.z)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.items[0].const == "hello"
        assert s.items[1].const == 6
        assert s.items[2].const == "foo"
        assert s.items[3].const == 7
        assert s.items[4].const == 2

    def test_specialize_and_star_args(self):
        class I(object):
            def execute(self, op, *args):
                if op == 0:
                    return args[0]+args[1]
                if op == 1:
                    return args[0] * args[1] + args[2]
            execute._annspecialcase_ = "specialize:arg(1)"

        def f(x, y):
            i = I()
            a = i.execute(0, x, y)
            b = i.execute(1, y, y, 5)
            return a+b

        a = self.RPythonAnnotator()
        s = a.build_types(f, [int, int])

        executedesc = a.bookkeeper.getdesc(I.execute.im_func)
        assert len(executedesc._cache) == 2

        assert len(executedesc._cache[(0, 'star', 2)].startblock.inputargs) == 4
        assert len(executedesc._cache[(1, 'star', 3)].startblock.inputargs) == 5

    def test_specialize_arg_or_var(self):
        def f(a):
            return 1
        f._annspecialcase_ = 'specialize:arg_or_var(0)'

        def fn(a):
            return f(3) + f(a)

        a = self.RPythonAnnotator()
        a.build_types(fn, [int])
        executedesc = a.bookkeeper.getdesc(f)
        assert sorted(executedesc._cache.keys()) == [None, (3,)]
        # we got two different special

    def test_specialize_call_location(self):
        def g(a):
            return a
        g._annspecialcase_ = "specialize:call_location"
        def f(x):
            return g(x)
        f._annspecialcase_ = "specialize:argtype(0)"
        def h(y):
            w = f(y)
            return int(f(str(y))) + w
        a = self.RPythonAnnotator()
        assert a.build_types(h, [int]) == annmodel.SomeInteger()

    def test_assert_list_doesnt_lose_info(self):
        class T(object):
            pass
        def g(l):
            assert isinstance(l, list)
            return l
        def f():
            l = [T()]
            return g(l)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        s_item = listitem(s)
        assert isinstance(s_item, annmodel.SomeInstance)
        assert s_item.classdef is a.bookkeeper.getuniqueclassdef(T)

    def test_int_str_mul(self):
        def f(x,a,b):
            return a*x+x*b
        a = self.RPythonAnnotator()
        s = a.build_types(f, [str,int,int])
        assert s.knowntype == str

    def test_list_tuple(self):
        def g0(x):
            return list(x)
        def g1(x):
            return list(x)
        def f(n):
            l1 = g0(())
            l2 = g1((1,))
            if n:
                t = (1,)
            else:
                t = (2,)
            l3 = g1(t)
            return l1, l2, l3
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])
        assert listitem(s.items[0]) == annmodel.SomeImpossibleValue()
        assert listitem(s.items[1]).knowntype == int
        assert listitem(s.items[2]).knowntype == int

    def test_empty_list(self):
        def f():
            l = []
            return bool(l)
        def g():
            l = []
            x = bool(l)
            l.append(1)
            return x, bool(l)

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.const == False

        a = self.RPythonAnnotator()
        s = a.build_types(g, [])

        assert s.items[0].knowntype == bool and not s.items[0].is_constant()
        assert s.items[1].knowntype == bool and not s.items[1].is_constant()

    def test_empty_dict(self):
        def f():
            d = {}
            return bool(d)
        def g():
            d = {}
            x = bool(d)
            d['a'] = 1
            return x, bool(d)

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.const == False

        a = self.RPythonAnnotator()
        s = a.build_types(g, [])

        assert s.items[0].knowntype == bool and not s.items[0].is_constant()
        assert s.items[1].knowntype == bool and not s.items[1].is_constant()

    def test_call_two_funcs_but_one_can_only_raise(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.call_two_funcs_but_one_can_only_raise,
                          [int])
        assert s == a.bookkeeper.immutablevalue(None)

    def test_reraiseKeyError(self):
        def f(dic):
            try:
                dic[5]
            except KeyError:
                raise
        a = self.RPythonAnnotator()
        a.build_types(f, [somedict(annmodel.s_Int, annmodel.s_Int)])
        fg = graphof(a, f)
        et, ev = fg.exceptblock.inputargs
        t = annmodel.SomeType()
        t.const = KeyError
        t.is_type_of = [ev]
        assert a.binding(et) == t
        assert isinstance(a.binding(ev), annmodel.SomeInstance) and a.binding(ev).classdef == a.bookkeeper.getuniqueclassdef(KeyError)

    def test_reraiseAnything(self):
        def f(dic):
            try:
                dic[5]
            except:
                raise
        a = self.RPythonAnnotator()
        a.build_types(f, [somedict(annmodel.s_Int, annmodel.s_Int)])
        fg = graphof(a, f)
        et, ev = fg.exceptblock.inputargs
        t = annmodel.SomeType()
        t.is_type_of = [ev]
        t.const = KeyError    # IndexError ignored because 'dic' is a dict
        assert a.binding(et) == t
        assert isinstance(a.binding(ev), annmodel.SomeInstance) and a.binding(ev).classdef == a.bookkeeper.getuniqueclassdef(KeyError)

    def test_exception_mixing(self):
        def h():
            pass

        def g():
            pass

        class X(Exception):
            def __init__(self, x=0):
                self.x = x

        def f(a, l):
            if a==1:
                raise X
            elif a==2:
                raise X(1)
            elif a==3:
                raise X(4)
            else:
                try:
                    l[0]
                    x,y = l
                    g()
                finally:
                    h()
        a = self.RPythonAnnotator()
        a.build_types(f, [int, somelist(annmodel.s_Int)])
        fg = graphof(a, f)
        et, ev = fg.exceptblock.inputargs
        t = annmodel.SomeType()
        t.is_type_of = [ev]
        assert a.binding(et) == t
        assert isinstance(a.binding(ev), annmodel.SomeInstance) and a.binding(ev).classdef == a.bookkeeper.getuniqueclassdef(Exception)

    def test_try_except_raise_finally1(self):
        def h(): pass
        def g(): pass
        class X(Exception): pass
        def f():
            try:
                try:
                    g()
                except X:
                    h()
                    raise
            finally:
                h()
        a = self.RPythonAnnotator()
        a.build_types(f, [])
        fg = graphof(a, f)
        et, ev = fg.exceptblock.inputargs
        t = annmodel.SomeType()
        t.is_type_of = [ev]
        assert a.binding(et) == t
        assert isinstance(a.binding(ev), annmodel.SomeInstance) and a.binding(ev).classdef == a.bookkeeper.getuniqueclassdef(Exception)

    def test_inplace_div(self):
        def f(n):
            n /= 2
            return n / 2
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.knowntype == int

    def test_prime(self):
        a = self.RPythonAnnotator()
        s = a.build_types(snippet.prime, [int])
        assert s.knowntype == bool

    def test_and_bool_coalesce(self):
        def f(a,b,c,d,e):
            x = a and b
            if x:
                return d,c
            return e,c
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int, str, a.bookkeeper.immutablevalue(1.0), a.bookkeeper.immutablevalue('d'), a.bookkeeper.immutablevalue('e')])
        assert s == annmodel.SomeTuple([annmodel.SomeChar(), a.bookkeeper.immutablevalue(1.0)])

    def test_bool_coalesce2(self):
        def f(a,b,a1,b1,c,d,e):
            x = (a or  b) and (a1 or b1)
            if x:
                return d,c
            return e,c
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int, str, float, somelist(annmodel.s_Int),
                              a.bookkeeper.immutablevalue(1.0),
                              a.bookkeeper.immutablevalue('d'),
                              a.bookkeeper.immutablevalue('e')])
        assert s == annmodel.SomeTuple([annmodel.SomeChar(),
                                        a.bookkeeper.immutablevalue(1.0)])

    def test_bool_coalesce_sanity(self):
        def f(a):
            while a:
                pass
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s == a.bookkeeper.immutablevalue(None)

    def test_non_None_path(self):
        class C:
            pass
        def g(c):
            if c is None:
                return C()
            return c
        def f(x):
            if x:
                c = None
            else:
                c = C()
            return g(c)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])
        assert s.can_be_none() == False

    def test_can_be_None_path(self):
        class C:
            pass
        def f(x):
            if x:
                c = None
            else:
                c = C()
            return isinstance(c, C)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])
        assert not s.is_constant()

    def test_nonneg_cleverness(self):
        def f(a, b, c, d, e, f, g, h):
            if a < 0: a = 0
            if b <= 0: b = 0
            if c >= 0:
                pass
            else:
                c = 0
            if d < a: d = a
            if e <= b: e = 1
            if c > f: f = 2
            if d >= g: g = 3
            if h != a: h = 0
            return a, b, c, d, e, f, g, h
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int]*8)
        assert s == annmodel.SomeTuple([annmodel.SomeInteger(nonneg=True)] * 8)

    def test_general_nonneg_cleverness(self):
        def f(a, b, c, d, e, f, g, h):
            if a < 0: a = 0
            if b <= 0: b = 0
            if c >= 0:
                pass
            else:
                c = 0
            if d < a: d = a
            if e <= b: e = 1
            if c > f: f = 2
            if d >= g: g = 3
            if h != a: h = 0
            return a, b, c, d, e, f, g, h
        a = self.RPythonAnnotator()
        s = a.build_types(f, [r_longlong]*8)
        assert s == annmodel.SomeTuple([annmodel.SomeInteger(nonneg=True, knowntype=r_longlong)] * 8)


    def test_more_nonneg_cleverness(self):
        def f(start, stop):
            assert 0 <= start <= stop
            return start, stop
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int, int])
        assert s == annmodel.SomeTuple([annmodel.SomeInteger(nonneg=True)] * 2)

    def test_more_general_nonneg_cleverness(self):
        def f(start, stop):
            assert 0 <= start <= stop
            return start, stop
        a = self.RPythonAnnotator()
        s = a.build_types(f, [r_longlong, r_longlong])
        assert s == annmodel.SomeTuple([annmodel.SomeInteger(nonneg=True, knowntype=r_longlong)] * 2)

    def test_nonneg_cleverness_is_gentle_with_unsigned(self):
        def witness1(x):
            pass
        def witness2(x):
            pass
        def f(x):
            if 0 < x:
                witness1(x)
            if x > 0:
                witness2(x)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [annmodel.SomeInteger(unsigned=True)])
        wg1 = graphof(a, witness1)
        wg2 = graphof(a, witness2)
        assert a.binding(wg1.getargs()[0]).unsigned is True
        assert a.binding(wg2.getargs()[0]).unsigned is True

    def test_general_nonneg_cleverness_is_gentle_with_unsigned(self):
        def witness1(x):
            pass
        def witness2(x):
            pass
        def f(x):
            if 0 < x:
                witness1(x)
            if x > 0:
                witness2(x)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [annmodel.SomeInteger(knowntype=r_ulonglong)])
        wg1 = graphof(a, witness1)
        wg2 = graphof(a, witness2)
        assert a.binding(wg1.getargs()[0]).knowntype is r_ulonglong
        assert a.binding(wg2.getargs()[0]).knowntype is r_ulonglong

    def test_nonneg_cleverness_in_max(self):
        def f(x):
            return max(x, 0) + max(0, x)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.nonneg

    def test_attr_moving_into_parent(self):
        class A: pass
        class B(A): pass
        a1 = A()
        b1 = B()
        b1.stuff = a1
        a1.stuff = None
        def f():
            return b1.stuff
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeInstance)
        assert not s.can_be_None
        assert s.classdef is a.bookkeeper.getuniqueclassdef(A)

    def test_class_attribute(self):
        class A:
            stuff = 42
        class B(A):
            pass
        def f():
            b = B()
            return b.stuff
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s == a.bookkeeper.immutablevalue(42)

    def test_attr_recursive_getvalue(self):
        class A: pass
        a2 = A()
        a2.stuff = None
        a1 = A()
        a1.stuff = a2
        def f():
            return a1.stuff
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeInstance)
        assert s.can_be_None
        assert s.classdef is a.bookkeeper.getuniqueclassdef(A)

    def test_long_list_recursive_getvalue(self):
        class A: pass
        lst = []
        for i in range(500):
            a1 = A()
            a1.stuff = lst
            lst.append(a1)
        def f():
            A().stuff = None
            return (A().stuff, lst)[1]
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeList)
        s_item = s.listdef.listitem.s_value
        assert isinstance(s_item, annmodel.SomeInstance)

    def test_immutable_dict(self):
        d = {4: "hello",
             5: "world"}
        def f(n):
            return d[n]
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeString)

    def test_immutable_recursive_list(self):
        l = []
        l.append(l)
        def f():
            return l
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeList)
        s_item = s.listdef.listitem.s_value
        assert isinstance(s_item, annmodel.SomeList)
        assert s_item.listdef.same_as(s.listdef)

    def test_defaults_with_list_or_dict(self):
        def fn1(a=[]):
            return a
        def fn2(a={}):
            return a
        def f():
            fn1()
            fn2()
            return fn1([6, 7]), fn2({2: 3, 4: 5})
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeTuple)
        s1, s2 = s.items
        assert not s1.is_constant()
        assert not s2.is_constant()
        assert isinstance(s1.listdef.listitem. s_value, annmodel.SomeInteger)
        assert isinstance(s2.dictdef.dictkey.  s_value, annmodel.SomeInteger)
        assert isinstance(s2.dictdef.dictvalue.s_value, annmodel.SomeInteger)

    def test_pbc_union(self):
        class A:
            def meth(self):
                return 12
        class B(A):
            pass
        class C(B):
            pass
        def f(i):
            if i:
                f(0)
                x = B()
            else:
                x = C()
            return x.meth()
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s == a.bookkeeper.immutablevalue(12)

    def test_int(self):
        def f(x, s):
            return int(x) + int(s) + int(s, 16)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int, str])
        assert s.knowntype == int

    def test_int_nonneg(self):
        def f(x, y):
            assert x >= 0
            return int(x) + int(y == 3)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int, int])
        assert isinstance(s, annmodel.SomeInteger)
        assert s.nonneg

    def test_listitem_merge_asymmetry_bug(self):
        class K:
            pass
        def mutr(k, x, i):
            k.l2 = [x] + k.l2 # this involves a side-effectful union and unification, with this order
                              # of arguments some reflowing was missed
            k.l2[i] = x
        def witness(i):
            pass
        def trouble(k):
            l = k.l1 + k.l2
            for i in range(len(l)):
                witness(l[i])
        def f(flag, k, x, i):
            if flag:
                k = K()
                k.l1 = []
                k.l2 = []
            trouble(k)
            mutr(k, x, i)
        a = self.RPythonAnnotator()
        a.build_types(f, [bool, K,  int, int])
        g = graphof(a, witness)
        assert a.binding(g.getargs()[0]).knowntype == int

    # check RPython static semantics of isinstance(x,bool|int) as needed for wrap

    def test_isinstance_int_bool(self):
        def f(x):
            if isinstance(x, int):
                if isinstance(x, bool):
                    return "bool"
                return "int"
            return "dontknow"
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])
        assert s.const == "bool"
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.const == "int"
        a = self.RPythonAnnotator()
        s = a.build_types(f, [float])
        assert s.const == "dontknow"

    def test_hidden_method(self):
        class Base:
            def method(self):
                return ["should be hidden"]
            def indirect(self):
                return self.method()
        class A(Base):
            def method(self):
                return "visible"
        class B(A):       # note: it's a chain of subclasses
            def method(self):
                return None
        def f(flag):
            if flag:
                obj = A()
            else:
                obj = B()
            return obj.indirect()
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])
        assert annmodel.SomeString(can_be_None=True).contains(s)

    def test_dont_see_AttributeError_clause(self):
        class Stuff:
            def _freeze_(self):
                return True
            def createcompiler(self):
                try:
                    return self.default_compiler
                except AttributeError:
                    compiler = "yadda"
                    self.default_compiler = compiler
                    return compiler
        stuff = Stuff()
        stuff.default_compiler = 123
        def f():
            return stuff.createcompiler()
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s == a.bookkeeper.immutablevalue(123)

    def test_class_attribute_is_an_instance_of_itself(self):
        class Base:
            hello = None
        class A(Base):
            pass
        A.hello = globalA = A()
        def f():
            return (Base().hello, globalA)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeTuple)
        assert isinstance(s.items[0], annmodel.SomeInstance)
        assert s.items[0].classdef is a.bookkeeper.getuniqueclassdef(A)
        assert s.items[0].can_be_None
        assert s.items[1] == a.bookkeeper.immutablevalue(A.hello)

    def test_dict_and_none(self):
        def f(i):
            if i:
                return {}
            else:
                return None
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.knowntype == annmodel.SomeOrderedDict.knowntype

    def test_const_list_and_none(self):
        def g(l=None):
            return l is None
        L = [1,2]
        def f():
            g()
            return g(L)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.knowntype == bool
        assert not s.is_constant()

    def test_const_dict_and_none(self):
        def g(d=None):
            return d is None
        D = {1:2}
        def f():
            g(D)
            return g()
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.knowntype == bool
        assert not s.is_constant()

    def test_issubtype_and_const(self):
        class A(object):
            pass
        class B(object):
            pass
        class C(A):
            pass
        b = B()
        c = C()
        def g(f):
            if f == 1:
                x = b
            elif f == 2:
                x = c
            else:
                x = C()
            t = type(x)
            return issubclass(t, A)

        a = self.RPythonAnnotator()
        x = annmodel.SomeInteger()
        x.const = 1
        s = a.build_types(g, [x])
        assert s.const == False
        a = self.RPythonAnnotator()
        x = annmodel.SomeInteger()
        x.const = 2
        s = a.build_types(g, [x])
        assert s.const == True

    def test_reading_also_generalizes(self):
        def f1(i):
            d = {'c': i}
            return d['not-a-char'], d
        a = self.RPythonAnnotator()
        s = a.build_types(f1, [int])
        assert dictkey(s.items[1]).__class__ == annmodel.SomeString
        def f2(i):
            d = {'c': i}
            return d.get('not-a-char', i+1), d
        a = self.RPythonAnnotator()
        s = a.build_types(f2, [int])
        assert dictkey(s.items[1]).__class__ == annmodel.SomeString
        def f3(i):
            d = {'c': i}
            return 'not-a-char' in d, d
        a = self.RPythonAnnotator()
        s = a.build_types(f3, [int])
        assert dictkey(s.items[1]).__class__ == annmodel.SomeString
        def f4():
            lst = ['a', 'b', 'c']
            return 'not-a-char' in lst, lst
        a = self.RPythonAnnotator()
        s = a.build_types(f4, [])
        assert listitem(s.items[1]).__class__ == annmodel.SomeString
        def f5():
            lst = ['a', 'b', 'c']
            return lst.index('not-a-char'), lst
        a = self.RPythonAnnotator()
        s = a.build_types(f5, [])
        assert listitem(s.items[1]).__class__ == annmodel.SomeString

    def test_true_str_is_not_none(self):
        def f(s):
            if s:
                return s
            else:
                return ''
        def g(i):
            if i:
                return f(None)
            else:
                return f('')
        a = self.RPythonAnnotator()
        s = a.build_types(g, [int])
        assert s.knowntype == str
        assert not s.can_be_None

    def test_true_func_is_not_none(self):
        def a1():
            pass
        def a2():
            pass
        def f(a):
            if a:
                return a
            else:
                return a2
        def g(i):
            if i:
                return f(None)
            else:
                return f(a1)
        a = self.RPythonAnnotator()
        s = a.build_types(g, [int])
        assert not s.can_be_None

    def test_string_noNUL_canbeNone(self):
        def f(a):
            if a:
                return "abc"
            else:
                return None
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.can_be_None
        assert s.no_nul

    def test_str_or_None(self):
        def f(a):
            if a:
                return "abc"
            else:
                return None
        def g(a):
            x = f(a)
            if x is None:
                return "abcd"
            return x
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.can_be_None
        assert s.no_nul

    def test_emulated_pbc_call_simple(self):
        def f(a,b):
            return a + b
        from rpython.annotator import annrpython
        a = annrpython.RPythonAnnotator()
        from rpython.annotator import model as annmodel

        s_f = a.bookkeeper.immutablevalue(f)
        a.bookkeeper.emulate_pbc_call('f', s_f, [annmodel.SomeInteger(), annmodel.SomeInteger()])
        a.complete()

        assert a.binding(graphof(a, f).getreturnvar()).knowntype == int
        fdesc = a.bookkeeper.getdesc(f)

        someint = annmodel.SomeInteger()

        assert (fdesc.get_s_signatures((2, (), False))
                == [([someint,someint],someint)])

    def test_emulated_pbc_call_callback(self):
        def f(a,b):
            return a + b
        from rpython.annotator import annrpython
        a = annrpython.RPythonAnnotator()
        from rpython.annotator import model as annmodel

        memo = []
        def callb(ann, graph):
            memo.append(annmodel.SomeInteger() == ann.binding(graph.getreturnvar()))

        s_f = a.bookkeeper.immutablevalue(f)
        s = a.bookkeeper.emulate_pbc_call('f', s_f, [annmodel.SomeInteger(), annmodel.SomeInteger()],
                                          callback=callb)
        assert s == annmodel.SomeImpossibleValue()
        a.complete()

        assert a.binding(graphof(a, f).getreturnvar()).knowntype == int
        assert len(memo) >= 1
        for t in memo:
            assert t

    def test_iterator_union(self):
        def it(d):
            return d.iteritems()
        d0 = {1:2}
        def f():
            it(d0)
            return it({1:2})
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeIterator)
        assert s.variant == ('items',)

    def test_iteritems_str0(self):
        def it(d):
            return d.iteritems()
        def f():
            d0 = {'1a': '2a', '3': '4'}
            for item in it(d0):
                return "%s=%s" % item
            raise ValueError
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeString)
        assert s.no_nul

    def test_mul_str0(self):
        def f(s):
            return s*10
        a = self.RPythonAnnotator()
        s = a.build_types(f, [annmodel.SomeString(no_nul=True)])
        assert isinstance(s, annmodel.SomeString)
        assert s.no_nul

    def test_getitem_str0(self):
        def f(s, n):
            if n == 1:
                return s[0]
            elif n == 2:
                return s[1]
            elif n == 3:
                return s[1:]
            return s
        a = self.RPythonAnnotator()
        a.translator.config.translation.check_str_without_nul = True

        s = a.build_types(f, [annmodel.SomeString(no_nul=True),
                              annmodel.SomeInteger()])
        assert isinstance(s, annmodel.SomeString)
        assert s.no_nul

    def test_non_none_and_none_with_isinstance(self):
        class A(object):
            pass
        class B(A):
            pass
        def g(x):
            if isinstance(x, A):
                return x
            return None
        def f():
            g(B())
            return g(None)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef == a.bookkeeper.getuniqueclassdef(B)

    def test_type_is_no_improvement(self):
        class B(object):
            pass
        class C(B):
            pass
        class D(B):
            pass
        def f(x):
            if type(x) is C:
                return x
            raise Exception
        a = self.RPythonAnnotator()
        s = a.build_types(f, [D])
        assert s == annmodel.SomeImpossibleValue()

    def test_is_constant_instance(self):
        class A(object):
            pass
        prebuilt_instance = A()
        def f(x):
            if x is prebuilt_instance:
                return x
            raise Exception
        a = self.RPythonAnnotator()
        s = a.build_types(f, [A])
        assert s.is_constant()
        assert s.const is prebuilt_instance

    def test_call_memoized_function(self):
        fr1 = Freezing()
        fr2 = Freezing()
        def getorbuild(key):
            a = 1
            if key is fr1:
                result = eval("a+2")
            else:
                result = eval("a+6")
            return result
        getorbuild._annspecialcase_ = "specialize:memo"

        def f1(i):
            if i > 0:
                fr = fr1
            else:
                fr = fr2
            return getorbuild(fr)

        a = self.RPythonAnnotator()
        s = a.build_types(f1, [int])
        assert s.knowntype == int

    def test_call_memoized_function_with_bools(self):
        fr1 = Freezing()
        fr2 = Freezing()
        def getorbuild(key, flag1, flag2):
            a = 1
            if key is fr1:
                result = eval("a+2")
            else:
                result = eval("a+6")
            if flag1:
                result += 100
            if flag2:
                result += 1000
            return result
        getorbuild._annspecialcase_ = "specialize:memo"

        def f1(i):
            if i > 0:
                fr = fr1
            else:
                fr = fr2
            return getorbuild(fr, i % 2 == 0, i % 3 == 0)

        a = self.RPythonAnnotator()
        s = a.build_types(f1, [int])
        assert s.knowntype == int

    def test_stored_bound_method(self):
        # issue 129
        class H:
            def h(self):
                return 42
        class C:
            def __init__(self, func):
                self.f = func
            def do(self):
                return self.f()
        def g():
            h = H()
            c = C(h.h)
            return c.do()

        a = self.RPythonAnnotator()
        s = a.build_types(g, [])
        assert s.is_constant()
        assert s.const == 42

    def test_stored_bound_method_2(self):
        # issue 129
        class H:
            pass
        class H1(H):
            def h(self):
                return 42
        class H2(H):
            def h(self):
                return 17
        class C:
            def __init__(self, func):
                self.f = func
            def do(self):
                return self.f()
        def g(flag):
            if flag:
                h = H1()
            else:
                h = H2()
            c = C(h.h)
            return c.do()

        a = self.RPythonAnnotator()
        s = a.build_types(g, [int])
        assert s.knowntype == int
        assert not s.is_constant()

    def test_getorbuild_as_attr(self):
        from rpython.rlib.cache import Cache
        class SpaceCache(Cache):
            def _build(self, callable):
                return callable()
        class CacheX(Cache):
            def _build(self, key):
                return key.x
        class CacheY(Cache):
            def _build(self, key):
                return key.y
        class X:
            def __init__(self, x):
                self.x = x
            def _freeze_(self):
                return True
        class Y:
            def __init__(self, y):
                self.y = y
            def _freeze_(self):
                return True
        X1 = X(1)
        Y2 = Y("hello")
        fromcache = SpaceCache().getorbuild
        def f():
            return (fromcache(CacheX).getorbuild(X1),
                    fromcache(CacheY).getorbuild(Y2))

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.items[0].knowntype == int
        assert s.items[1].knowntype == str

    def test_constant_bound_method(self):
        class C:
            def __init__(self, value):
                self.value = value
            def meth(self):
                return self.value
        meth = C(1).meth
        def f():
            return meth()
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.knowntype == int

    def test_annotate__del__(self):
        class A(object):
            def __init__(self):
                self.a = 2
            def __del__(self):
                self.a = 1
        def f():
            return A().a
        a = self.RPythonAnnotator()
        t = a.translator
        s = a.build_types(f, [])
        assert s.knowntype == int
        graph = tgraphof(t, A.__del__.im_func)
        assert graph.startblock in a.annotated

    def test_annotate__del__baseclass(self):
        class A(object):
            def __init__(self):
                self.a = 2
            def __del__(self):
                self.a = 1
        class B(A):
            def __init__(self):
                self.a = 3
        def f():
            return B().a
        a = self.RPythonAnnotator()
        t = a.translator
        s = a.build_types(f, [])
        assert s.knowntype == int
        graph = tgraphof(t, A.__del__.im_func)
        assert graph.startblock in a.annotated

    def test_annotate_type(self):
        class A:
            pass
        x = [A(), A()]
        def witness(t):
            return type(t)
        def get(i):
            return x[i]
        def f(i):
            witness(None)
            return witness(get(i))

        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeType)

    def test_annotate_iter_empty_container(self):
        def f():
            n = 0
            d = {}
            for x in []:                n += x
            for y in d:                 n += y
            for z in d.iterkeys():      n += z
            for s in d.itervalues():    n += s
            for t, u in d.items():      n += t * u
            for t, u in d.iteritems():  n += t * u
            return n

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.is_constant()
        assert s.const == 0

    def test_mixin(self):
        class Mixin(object):
            _mixin_ = True

            def m(self, v):
                return v

        class Base(object):
            pass

        class A(Base, Mixin):
            pass

        class B(Base, Mixin):
            pass

        class C(B):
            pass

        def f():
            a = A()
            v0 = a.m(2)
            b = B()
            v1 = b.m('x')
            c = C()
            v2 = c.m('y')
            return v0, v1, v2

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s.items[0], annmodel.SomeInteger)
        assert isinstance(s.items[1], annmodel.SomeChar)
        assert isinstance(s.items[2], annmodel.SomeChar)

    def test_mixin_staticmethod(self):
        class Mixin(object):
            _mixin_ = True

            @staticmethod
            def m(v):
                return v

        class Base(object):
            pass

        class A(Base, Mixin):
            pass

        class B(Base, Mixin):
            pass

        class C(B):
            pass

        def f():
            a = A()
            v0 = a.m(2)
            b = B()
            v1 = b.m('x')
            c = C()
            v2 = c.m('y')
            return v0, v1, v2

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s.items[0], annmodel.SomeInteger)
        assert isinstance(s.items[1], annmodel.SomeChar)
        assert isinstance(s.items[2], annmodel.SomeChar)

    def test_mixin_first(self):
        class Mixin(object):
            _mixin_ = True
            def foo(self): return 4
        class Base(object):
            def foo(self): return 5
        class Concrete(Mixin, Base):
            pass
        def f():
            return Concrete().foo()

        assert f() == 4
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.const == 4

    def test_mixin_last(self):
        class Mixin(object):
            _mixin_ = True
            def foo(self): return 4
        class Base(object):
            def foo(self): return 5
        class Concrete(Base, Mixin):
            pass
        def f():
            return Concrete().foo()

        assert f() == 5
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.const == 5

    def test_mixin_concrete(self):
        class Mixin(object):
            _mixin_ = True
            def foo(self): return 4
        class Concrete(Mixin):
            def foo(self): return 5
        def f():
            return Concrete().foo()

        assert f() == 5
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.const == 5

    def test_multiple_mixins_mro(self):
        # an obscure situation, but it occurred in module/micronumpy/types.py
        class A(object):
            _mixin_ = True
            def foo(self): return 1
        class B(A):
            _mixin_ = True
            def foo(self): return 2
        class C(A):
            _mixin_ = True
        class D(B, C):
            _mixin_ = True
        class Concrete(D):
            pass
        def f():
            return Concrete().foo()

        assert f() == 2
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.const == 2

    def test_multiple_mixins_mro_2(self):
        class A(object):
            _mixin_ = True
            def foo(self): return 1
        class B(A):
            _mixin_ = True
            def foo(self): return 2
        class C(A):
            _mixin_ = True
        class Concrete(C, B):
            pass
        def f():
            return Concrete().foo()

        assert f() == 2
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.const == 2

    def test_cannot_use_directly_mixin(self):
        class A(object):
            _mixin_ = True
        #
        def f():
            return A()
        a = self.RPythonAnnotator()
        py.test.raises(annmodel.AnnotatorError, a.build_types, f, [])
        #
        class B(object):
            pass
        x = B()
        def g():
            return isinstance(x, A)
        py.test.raises(annmodel.AnnotatorError, a.build_types, g, [])

    def test_import_from_mixin(self):
        class M(object):
            def f(self):
                return self.a
        class I(object):
            objectmodel.import_from_mixin(M)
            def __init__(self, i):
                self.a = i
        class S(object):
            objectmodel.import_from_mixin(M)
            def __init__(self, s):
                self.a = s
        def f(n):
            return (I(n).f(), S("a" * n).f())

        assert f(3) == (3, "aaa")
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s.items[0], annmodel.SomeInteger)
        assert isinstance(s.items[1], annmodel.SomeString)

    def test___class___attribute(self):
        class Base(object): pass
        class A(Base): pass
        class B(Base): pass
        class C(A): pass
        def seelater():
            C()
        def f(n):
            if n == 1:
                x = A()
            else:
                x = B()
            y = B()
            result = x.__class__, y.__class__
            seelater()
            return result

        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s.items[0], annmodel.SomePBC)
        assert len(s.items[0].descriptions) == 4
        assert isinstance(s.items[1], annmodel.SomePBC)
        assert len(s.items[1].descriptions) == 1

    def test_slots(self):
        # check that the annotator ignores slots instead of being
        # confused by them showing up as 'member' objects in the class
        class A(object):
            __slots__ = ('a', 'b')
        def f(x):
            a = A()
            a.b = x
            return a.b

        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.knowntype == int

    def test_slots_reads(self):
        class A(object):
            __slots__ = ()
        class B(A):
            def __init__(self, x):
                self.x = x
        def f(x):
            if x:
                a = A()
            else:
                a = B(x)
            return a.x   # should explode here

        a = self.RPythonAnnotator()
        e = py.test.raises(Exception, a.build_types, f, [int])
        # this should explode on reading the attribute 'a.x', but it can
        # sometimes explode on 'self.x = x', which does not make much sense.
        # But it looks hard to fix in general: we don't know yet during 'a.x'
        # if the attribute x will be read-only or read-write.

    def test_unboxed_value(self):
        class A(object):
            __slots__ = ()
        class C(A, objectmodel.UnboxedValue):
            __slots__ = unboxedattrname = 'smallint'
        def f(n):
            return C(n).smallint

        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.knowntype == int


    def test_annotate_bool(self):
        def f(x):
            return ~x
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])
        assert s.knowntype == int


        def f(x):
            return -x
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])
        assert s.knowntype == int

        def f(x):
            return +x
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])
        assert s.knowntype == int

        def f(x):
            return abs(x)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])
        assert s.knowntype == int

        def f(x):
            return int(x)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool])
        assert s.knowntype == int


        def f(x, y):
            return x + y
        a = self.RPythonAnnotator()
        s = a.build_types(f, [bool, int])
        assert s.knowntype == int

        a = self.RPythonAnnotator()
        s = a.build_types(f, [int, bool])
        assert s.knowntype == int



    def test_annotate_rarith(self):
        inttypes = [int, r_uint, r_longlong, r_ulonglong]
        for inttype in inttypes:
            c = inttype()
            def f():
                return c
            a = self.RPythonAnnotator()
            s = a.build_types(f, [])
            assert isinstance(s, annmodel.SomeInteger)
            assert s.knowntype == inttype
            assert s.unsigned == (inttype(-1) > 0)

        for inttype in inttypes:
            def f():
                return inttype(0)
            a = self.RPythonAnnotator()
            s = a.build_types(f, [])
            assert isinstance(s, annmodel.SomeInteger)
            assert s.knowntype == inttype
            assert s.unsigned == (inttype(-1) > 0)

        for inttype in inttypes:
            def f(x):
                return x
            a = self.RPythonAnnotator()
            s = a.build_types(f, [inttype])
            assert isinstance(s, annmodel.SomeInteger)
            assert s.knowntype == inttype
            assert s.unsigned == (inttype(-1) > 0)

    def test_annotate_rshift(self):
        def f(x):
            return x >> 2
        a = self.RPythonAnnotator()
        s = a.build_types(f, [annmodel.SomeInteger(nonneg=True)])
        assert isinstance(s, annmodel.SomeInteger)
        assert s.nonneg

    def test_prebuilt_mutables(self):
        class A:
            pass
        class B:
            pass
        a1 = A()
        a2 = A()
        a1.d = {}    # this tests confusion between the two '{}', which
        a2.d = {}    # compare equal
        a1.l = []
        a2.l = []
        b = B()
        b.d1 = a1.d
        b.d2 = a2.d
        b.l1 = a1.l
        b.l2 = a2.l

        def dmutate(d):
            d[123] = 321

        def lmutate(l):
            l.append(42)

        def readout(d, l):
            return len(d) + len(l)

        def f():
            dmutate(b.d1)
            dmutate(b.d2)
            dmutate(a1.d)
            dmutate(a2.d)
            lmutate(b.l1)
            lmutate(b.l2)
            lmutate(a1.l)
            lmutate(a2.l)
            return readout(a1.d, a1.l) + readout(a2.d, a2.l)

        a = self.RPythonAnnotator()
        a.build_types(f, [])
        v1, v2 = graphof(a, readout).getargs()
        assert not a.binding(v1).is_constant()
        assert not a.binding(v2).is_constant()

    def test_prebuilt_mutables_dont_use_eq(self):
        # test that __eq__ is not called during annotation, at least
        # when we know that the classes differ anyway
        class Base(object):
            def __eq__(self, other):
                if self is other:
                    return True
                raise ValueError
            def __hash__(self):
                return 42
        class A(Base):
            pass
        class B(Base):
            pass
        a1 = A()
        a2 = B()
        a1.x = 5
        a2.x = 6

        def f():
            return a1.x + a2.x

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert s.knowntype == int

    def test_chr_out_of_bounds(self):
        def g(n, max):
            if n < max:
                return chr(n)
            else:
                return '?'
        def fun(max):
            v = g(1000, max)
            return g(ord(v), max)

        a = self.RPythonAnnotator()
        s = a.build_types(fun, [int])
        assert isinstance(s, annmodel.SomeChar)

    def test_range_nonneg(self):
        def fun(n, k):
            for i in range(n):
                if k == 17:
                    return i
            return 0
        a = self.RPythonAnnotator()
        s = a.build_types(fun, [int, int])
        assert isinstance(s, annmodel.SomeInteger)
        assert s.nonneg

    def test_range_nonneg_variablestep(self):
        def get_step(n):
            if n == 1:
                return 2
            else:
                return 3
        def fun(n, k):
            step = get_step(n)
            for i in range(0, n, step):
                if k == 17:
                    return i
            return 0
        a = self.RPythonAnnotator()
        s = a.build_types(fun, [int, int])
        assert isinstance(s, annmodel.SomeInteger)
        assert s.nonneg

    def test_reverse_range_nonneg(self):
        def fun(n, k):
            for i in range(n-1, -1, -1):
                if k == 17:
                    return i
            return 0
        a = self.RPythonAnnotator()
        s = a.build_types(fun, [int, int])
        assert isinstance(s, annmodel.SomeInteger)
        assert s.nonneg

    def test_sig(self):
        def fun(x, y):
            return x+y
        s_nonneg = annmodel.SomeInteger(nonneg=True)
        fun._annenforceargs_ = Sig(int, s_nonneg)

        a = self.RPythonAnnotator()
        s = a.build_types(fun, [s_nonneg, s_nonneg])
        assert isinstance(s, annmodel.SomeInteger)
        assert not s.nonneg
        py.test.raises(Exception, a.build_types, fun, [int, int])

    def test_sig_simpler(self):
        def fun(x, y):
            return x+y
        s_nonneg = annmodel.SomeInteger(nonneg=True)
        fun._annenforceargs_ = (int, s_nonneg)

        a = self.RPythonAnnotator()
        s = a.build_types(fun, [s_nonneg, s_nonneg])
        assert isinstance(s, annmodel.SomeInteger)
        assert not s.nonneg
        py.test.raises(Exception, a.build_types, fun, [int, int])

    def test_sig_lambda(self):
        def fun(x, y):
            return y
        s_nonneg = annmodel.SomeInteger(nonneg=True)
        fun._annenforceargs_ = Sig(lambda s1,s2: s1, lambda s1,s2: s1)
        # means: the 2nd argument's annotation becomes the 1st argument's
        #        input annotation

        a = self.RPythonAnnotator()
        s = a.build_types(fun, [int, s_nonneg])
        assert isinstance(s, annmodel.SomeInteger)
        assert not s.nonneg
        py.test.raises(Exception, a.build_types, fun, [s_nonneg, int])

    def test_sig_bug(self):
        def g(x, y=5):
            return y == 5
        g._annenforceargs_ = (int, int)
        def fun(x):
            return g(x)
        a = self.RPythonAnnotator()
        s = a.build_types(fun, [int])
        assert s.knowntype is bool
        assert s.is_constant()

    def test_sig_list(self):
        def g(buf):
            buf.append(5)
        g._annenforceargs_ = ([int],)
        def fun():
            lst = []
            g(lst)
            return lst[0]
        a = self.RPythonAnnotator()
        s = a.build_types(fun, [])
        assert s.knowntype is int
        assert not s.is_constant()

    def test_slots_check(self):
        class Base(object):
            __slots__ = 'x'
        class A(Base):
            __slots__ = 'y'
            def m(self):
                return 65
        class C(Base):
            __slots__ = 'z'
            def m(self):
                return 67
        for attrname, works in [('x', True),
                                ('y', False),
                                ('z', False),
                                ('t', False)]:
            def fun(n):
                if n: o = A()
                else: o = C()
                setattr(o, attrname, 12)
                return o.m()
            a = self.RPythonAnnotator()
            if works:
                a.build_types(fun, [int])
            else:
                from rpython.annotator.classdef import NoSuchAttrError
                py.test.raises(NoSuchAttrError, a.build_types, fun, [int])

    def test_slots_enforce_attrs(self):
        class Superbase(object):
            __slots__ = 'x'
        class Base(Superbase):
            pass
        class A(Base):
            pass
        class B(Base):
            pass
        def fun(s):
            if s is None:   # known not to be None in this test
                o = B()
                o.x = 12
            elif len(s) > 5:
                o = A()
            else:
                o = Base()
            return o.x
        a = self.RPythonAnnotator()
        s = a.build_types(fun, [str])
        assert s == annmodel.s_ImpossibleValue   # but not blocked blocks

    def test_enforced_attrs_check(self):
        class Base(object):
            _attrs_ = 'x'
        class A(Base):
            _attrs_ = 'y'
            def m(self):
                return 65
        class C(Base):
            _attrs_ = 'z'
            def m(self):
                return 67
        for attrname, works in [('x', True),
                                ('y', False),
                                ('z', False),
                                ('t', False)]:
            def fun(n):
                if n: o = A()
                else: o = C()
                setattr(o, attrname, 12)
                return o.m()
            a = self.RPythonAnnotator()
            if works:
                a.build_types(fun, [int])
            else:
                from rpython.annotator.classdef import NoSuchAttrError
                py.test.raises(NoSuchAttrError, a.build_types, fun, [int])

    def test_attrs_enforce_attrs(self):
        class Superbase(object):
            _attrs_ = 'x'
        class Base(Superbase):
            pass
        class A(Base):
            pass
        class B(Base):
            pass
        def fun(s):
            if s is None:   # known not to be None in this test
                o = B()
                o.x = 12
            elif len(s) > 5:
                o = A()
            else:
                o = Base()
            return o.x
        a = self.RPythonAnnotator()
        s = a.build_types(fun, [str])
        assert s == annmodel.s_ImpossibleValue   # but not blocked blocks


    def test_pbc_enforce_attrs(self):
        class F(object):
            _attrs_ = ['foo',]

            def _freeze_(self):
                return True

        p1 = F()
        p2 = F()

        def g(): pass

        def f(x):
            if x:
                p = p1
            else:
                p = p2
            g()
            return p.foo

        a = self.RPythonAnnotator()
        a.build_types(f, [bool])

    def test_enforce_settled(self):
        class A(object):
            _settled_ = True

            def m(self):
                raise NotImplementedError

        class B(A):

            def m(self):
                return 1

            def n(self):
                return 1

        def fun(x):
            if x:
                a = A()
            else:
                a = B()

            return a.m()

        a = self.RPythonAnnotator()
        s = a.build_types(fun, [bool])
        assert s.knowntype == int

        def fun(x):
            if x:
                a = A()
            else:
                a = B()

            return a.n()

        a = self.RPythonAnnotator()
        py.test.raises(Exception, a.build_types, fun, [bool])

    def test_float_cmp(self):
        def fun(x, y):
            return (x < y,
                    x <= y,
                    x == y,
                    x != y,
                    x > y,
                    x >= y)

        a = self.RPythonAnnotator(policy=AnnotatorPolicy())
        s = a.build_types(fun, [float, float])
        assert [s_item.knowntype for s_item in s.items] == [bool] * 6

    def test_empty_range(self):
        def g(lst):
            total = 0
            for i in range(len(lst)):
                total += lst[i]
            return total
        def fun():
            return g([])

        a = self.RPythonAnnotator(policy=AnnotatorPolicy())
        s = a.build_types(fun, [])
        assert s.const == 0

    def test_compare_int_bool(self):
        def fun(x):
            return 50 < x
        a = self.RPythonAnnotator(policy=AnnotatorPolicy())
        s = a.build_types(fun, [bool])
        assert isinstance(s, annmodel.SomeBool)

    def test_long_as_intermediate_value(self):
        from sys import maxint
        from rpython.rlib.rarithmetic import intmask
        def fun(x):
            if x > 0:
                v = maxint
            else:
                v = -maxint
            return intmask(v * 10)
        P = AnnotatorPolicy()
        a = self.RPythonAnnotator(policy=P)
        s = a.build_types(fun, [bool])
        assert isinstance(s, annmodel.SomeInteger)

    def test_instance_with_flags(self):
        from rpython.rlib.jit import hint

        class A:
            _virtualizable_ = []
        class B(A):
            def meth(self):
                return self
        class C(A):
            def meth(self):
                return self

        def f(n):
            x = B()
            x = hint(x, access_directly=True)
            m = x.meth
            for i in range(n):
                x = C()
                m = x.meth
            return x, m, m()

        a = self.RPythonAnnotator()
        s = a.build_types(f, [a.bookkeeper.immutablevalue(0)])
        assert isinstance(s.items[0], annmodel.SomeInstance)
        assert s.items[0].flags == {'access_directly': True}
        assert isinstance(s.items[1], annmodel.SomePBC)
        assert len(s.items[1].descriptions) == 1
        assert s.items[1].any_description().flags == {'access_directly':
                                                           True}
        assert isinstance(s.items[2], annmodel.SomeInstance)
        assert s.items[2].flags == {'access_directly': True}

        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s.items[0], annmodel.SomeInstance)
        assert s.items[0].flags == {}
        assert isinstance(s.items[1], annmodel.SomePBC)
        assert isinstance(s.items[2], annmodel.SomeInstance)
        assert s.items[2].flags == {}

    def test_no_access_directly_on_heap(self):
        from rpython.rlib.jit import hint

        class A:
            _virtualizable_ = []

        class I:
            pass

        def f():
            x = A()
            x = hint(x, access_directly=True)
            i = I()
            i.x = x

        a = self.RPythonAnnotator()
        py.test.raises(Exception, a.build_types, f, [])


        class M:
            def __init__(self):
                self.l = []
                self.d = {}

        class C:
            def _freeze_(self):
                return True

            def __init__(self):
                self.m = M()
                self.l2 = []

        c = C()

        def f():
            x = A()
            x = hint(x, access_directly=True)
            c.m.l.append(x)

        a = self.RPythonAnnotator()
        py.test.raises(AssertionError, a.build_types, f, [])

        def f():
            x = A()
            x = hint(x, access_directly=True)
            c.m.d[None] = x

        a = self.RPythonAnnotator()
        py.test.raises(AssertionError, a.build_types, f, [])

        def f():
            x = A()
            x = hint(x, access_directly=True)
            c.m.d[x] = None

        a = self.RPythonAnnotator()
        py.test.raises(AssertionError, a.build_types, f, [])

    def test_ctr_location(self):
        class A:
            _annspecialcase_ = 'specialize:ctr_location'
            def __init__(self, x):
                self.x = x

        def f(n):
            a = A(2 * n)
            a.x = n
            b = A("")
            b.x = str(n)
            return len(b.x) + a.x
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeInteger)

    def test_weakref(self):
        import weakref

        class A:
            pass
        class B(A):
            pass
        class C(A):
            pass

        def f(n):
            if n:
                b = B()
                b.hello = 42
                r = weakref.ref(b)
            else:
                c = C()
                c.hello = 64
                r = weakref.ref(c)
            return r().hello
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeInteger)
        assert not s.is_constant()

    def test_float_pow_unsupported(self):
        def f(x, y):
            x **= y
            return x ** y
        a = self.RPythonAnnotator()
        py.test.raises(FlowingError, a.build_types, f, [int, int])
        a = self.RPythonAnnotator()
        py.test.raises(FlowingError, a.build_types, f, [float, float])

    def test_intcmp_bug(self):
        def g(x, y):
            return x <= y
        def f(x, y):
            if g(x, y):
                g(x, r_uint(y))
        a = self.RPythonAnnotator()
        py.test.raises(Exception, a.build_types, f, [int, int])

    def test_compare_with_zero(self):
        def g():
            should_not_see_this
        def f(n):
            assert n >= 0
            if n < 0:
                g()
            if not (n >= 0):
                g()
        a = self.RPythonAnnotator()
        a.build_types(f, [int])

    def test_r_singlefloat(self):
        z = r_singlefloat(0.4)
        def g(n):
            if n > 0:
                return r_singlefloat(n * 0.1)
            else:
                return z
        a = self.RPythonAnnotator()
        s = a.build_types(g, [int])
        assert isinstance(s, annmodel.SomeSingleFloat)

    def test_unicode_simple(self):
        def f():
            return u'xxx'

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeUnicodeString)

    def test_unicode(self):
        def g(n):
            if n > 0:
                return unichr(1234)
            else:
                return u"x\xe4x"

        def f(n):
            x = g(0)
            return x[n]

        a = self.RPythonAnnotator()
        s = a.build_types(g, [int])
        assert isinstance(s, annmodel.SomeUnicodeString)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeUnicodeCodePoint)

    def test_unicode_from_string(self):
        def f(x):
            return unicode(x)

        a = self.RPythonAnnotator()
        s = a.build_types(f, [str])
        assert isinstance(s, annmodel.SomeUnicodeString)

    def test_unicode_add(self):
        def f(x):
            return unicode(x) + unichr(1234)

        def g(x):
            return unichr(x) + unichr(2)

        a = self.RPythonAnnotator()
        s = a.build_types(f, [str])
        assert isinstance(s, annmodel.SomeUnicodeString)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeUnicodeString)

    def test_unicode_startswith(self):
        def f(x):
            return u'xxxx'.replace(x, u'z')

        a = self.RPythonAnnotator()
        s = a.build_types(f, [unicode])
        assert isinstance(s, annmodel.SomeUnicodeString)

    def test_unicode_buildtypes(self):
        def f(x):
            return x

        a = self.RPythonAnnotator()
        s = a.build_types(f, [unicode])
        assert isinstance(s, annmodel.SomeUnicodeString)

    def test_replace_annotations(self):
        def f(x):
            return 'a'.replace(x, 'b')

        a = self.RPythonAnnotator()
        s = a.build_types(f, [str])
        assert isinstance(s, annmodel.SomeString)
        assert s.no_nul

        def f(x):
            return u'a'.replace(x, u'b')

        a = self.RPythonAnnotator()
        s = a.build_types(f, [unicode])
        assert isinstance(s, annmodel.SomeUnicodeString)

    def test_unicode_char(self):
        def f(x, i):
            for c in x:
                if c == i:
                    return c
            return 'x'

        a = self.RPythonAnnotator()
        s = a.build_types(f, [unicode, str])
        assert isinstance(s, annmodel.SomeUnicodeCodePoint)

    def test_strformatting_unicode(self):
        def f(x):
            return '%s' % unichr(x)

        a = self.RPythonAnnotator()
        py.test.raises(annmodel.AnnotatorError, a.build_types, f, [int])
        def f(x):
            return '%s' % (unichr(x) * 3)

        a = self.RPythonAnnotator()
        py.test.raises(annmodel.AnnotatorError, a.build_types, f, [int])
        def f(x):
            return '%s%s' % (1, unichr(x))

        a = self.RPythonAnnotator()
        py.test.raises(annmodel.AnnotatorError, a.build_types, f, [int])
        def f(x):
            return '%s%s' % (1, unichr(x) * 15)

        a = self.RPythonAnnotator()
        py.test.raises(annmodel.AnnotatorError, a.build_types, f, [int])


    def test_strformatting_tuple(self):
        """
        A function which returns the result of interpolating a tuple of a
        single str into a str format string should be annotated as returning
        SomeString.
        """
        def f(x):
            return '%s' % (x,)

        a = self.RPythonAnnotator()
        s = a.build_types(f, [str])
        assert isinstance(s, annmodel.SomeString)

    def test_unicodeformatting(self):
        def f(x):
            return u'%s' % x

        a = self.RPythonAnnotator()
        s = a.build_types(f, [unicode])
        assert isinstance(s, annmodel.SomeUnicodeString)

    def test_unicodeformatting_tuple(self):
        def f(x):
            return u'%s' % (x,)

        a = self.RPythonAnnotator()
        s = a.build_types(f, [unicode])
        assert isinstance(s, annmodel.SomeUnicodeString)


    def test_negative_slice(self):
        def f(s, e):
            return [1, 2, 3][s:e]

        a = self.RPythonAnnotator()
        py.test.raises(annmodel.AnnotatorError, "a.build_types(f, [int, int])")
        a.build_types(f, [annmodel.SomeInteger(nonneg=True),
                          annmodel.SomeInteger(nonneg=True)])
        def f(x):
            return x[:-1]

        a.build_types(f, [str])

    def test_negative_number_find(self):
        def f(s, e):
            return "xyz".find("x", s, e)

        a = self.RPythonAnnotator()
        py.test.raises(annmodel.AnnotatorError, "a.build_types(f, [int, int])")
        a.build_types(f, [annmodel.SomeInteger(nonneg=True),
                          annmodel.SomeInteger(nonneg=True)])
        def f(s, e):
            return "xyz".rfind("x", s, e)

        py.test.raises(annmodel.AnnotatorError, "a.build_types(f, [int, int])")
        a.build_types(f, [annmodel.SomeInteger(nonneg=True),
                          annmodel.SomeInteger(nonneg=True)])

        def f(s, e):
            return "xyz".count("x", s, e)

        py.test.raises(annmodel.AnnotatorError, "a.build_types(f, [int, int])")
        a.build_types(f, [annmodel.SomeInteger(nonneg=True),
                          annmodel.SomeInteger(nonneg=True)])


    def test_setslice(self):
        def f():
            lst = [2, 5, 7]
            lst[1:2] = [4]
            return lst

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeList)
        assert not s.listdef.listitem.resized
        assert not s.listdef.listitem.immutable
        assert s.listdef.listitem.mutated

    def test_delslice(self):
        def f():
            lst = [2, 5, 7]
            del lst[1:2]
            return lst

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeList)
        assert s.listdef.listitem.resized

    def test_varargs(self):
        def f(*args):
            return args[0] + 42
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int, int])
        assert isinstance(s, annmodel.SomeInteger)

    def test_listitem_no_mutating(self):
        from rpython.rlib.debug import check_annotation
        called = []

        def checker(ann, bk):
            called.append(True)
            assert not ann.listdef.listitem.mutated
            ann.listdef.never_resize()

        def f():
            l = [1,2,3]
            check_annotation(l, checker)
            return l

        def g():
            l = f()
            l.append(4)

        a = self.RPythonAnnotator()
        py.test.raises(ListChangeUnallowed, a.build_types, g, [])
        assert called

    def test_listitem_no_mutating2(self):
        from rpython.rlib.debug import make_sure_not_resized

        def f():
            return make_sure_not_resized([1,2,3])

        def g():
            l = [1,2,3]
            l.append(4)
            return l

        def fn(i):
            if i:
                func = f
            else:
                func = g
            return func()

        a = self.RPythonAnnotator()
        a.translator.config.translation.list_comprehension_operations = True
        py.test.raises(ListChangeUnallowed, a.build_types, fn, [int])

    def test_listitem_never_resize(self):
        from rpython.rlib.debug import check_annotation

        def checker(ann, bk):
            ann.listdef.never_resize()

        def f():
            l = [1,2,3]
            l.append(4)
            check_annotation(l, checker)

        a = self.RPythonAnnotator()
        py.test.raises(ListChangeUnallowed, a.build_types, f, [])


    def test_len_of_empty_list(self):
        class X:
            pass
        def f(n):
            x = X()
            x.lst = None
            if n < 0:   # to showcase a failure of the famous "assert contains"
                return len(x.lst)
            x.lst = []
            return len(x.lst)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.const == 0

    def test_hash_sideeffect(self):
        class X:
            pass
        x1 = X()
        x2 = X()
        x3 = X()
        d = {(2, x1): 5, (3, x2): 7}
        def f(n, m):
            if   m == 1: x = x1
            elif m == 2: x = x2
            else:        x = x3
            return d[n, x]
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int, int])
        assert s.knowntype == int
        assert hasattr(x1, '__precomputed_identity_hash')
        assert hasattr(x2, '__precomputed_identity_hash')
        assert not hasattr(x3, '__precomputed_identity_hash')

    def test_contains_of_empty_dict(self):
        class A(object):
            def meth(self):
                return 1

        def g(x, y):
            d1 = {}
            for i in range(y):
                if x in d1:
                    return d1[x].meth()
                d1[i+1] = A()
            return 0

        a = self.RPythonAnnotator()
        s = a.build_types(g, [int, int])
        assert s.knowntype is int

        def f(x):
            d0 = {}
            if x in d0:
                d0[x].meth()
            return x+1

        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.knowntype is int

    def test_relax(self):
        def f(*args):
            return args[0] + args[1]
        f.relax_sig_check = True
        def g(x):
            return f(x, x - x)
        a = self.RPythonAnnotator()
        s = a.build_types(g, [int])
        assert a.bookkeeper.getdesc(f).getuniquegraph()

    def test_cannot_raise_ll_exception(self):
        from rpython.rtyper.annlowlevel import cast_instance_to_base_ptr
        #
        def f():
            e = OverflowError()
            lle = cast_instance_to_base_ptr(e)
            raise Exception(lle)
            # ^^^ instead, must cast back from a base ptr to an instance
        a = self.RPythonAnnotator()
        py.test.raises(AssertionError, a.build_types, f, [])

    def test_enumerate(self):
        def f():
            for i, x in enumerate(['a', 'b', 'c', 'd']):
                if i == 2:
                    return x
            return '?'
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeChar)

    def test_context_manager(self):
        class C:
            def __init__(self):
                pass
            def __enter__(self):
                self.x = 1
            def __exit__(self, *args):
                self.x = 3
        def f():
            c = C()
            with c:
                pass
            return c.x

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeInteger)
        # not a constant: both __enter__ and __exit__ have been annotated
        assert not s.is_constant()

    def test_make_sure_not_resized(self):
        from rpython.rlib.debug import make_sure_not_resized

        def pycode(consts):
            make_sure_not_resized(consts)
        def build1():
            return pycode(consts=[1])
        def build2():
            return pycode(consts=[0])
        def fn():
            build1()
            build2()

        a = self.RPythonAnnotator()
        a.translator.config.translation.list_comprehension_operations = True
        a.build_types(fn, [])
        # assert did not raise ListChangeUnallowed

    def test_return_immutable_list(self):
        class A:
            _immutable_fields_ = 'lst[*]'
        def f(n):
            a = A()
            l1 = [n, 0]
            l1[1] = n+1
            a.lst = l1
            return a.lst

        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.listdef.listitem.immutable

    def test_return_immutable_list_quasiimmut_field(self):
        class A:
            _immutable_fields_ = 'lst?[*]'
        def f(n):
            a = A()
            l1 = [n, 0]
            l1[1] = n+1
            a.lst = l1
            return a.lst

        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.listdef.listitem.immutable

    def test_immutable_list_is_actually_resized(self):
        class A:
            _immutable_fields_ = 'lst[*]'
        def f(n):
            a = A()
            l1 = [n]
            l1.append(n+1)
            a.lst = l1
            return a.lst

        a = self.RPythonAnnotator()
        py.test.raises(ListChangeUnallowed, a.build_types, f, [int])

    def test_immutable_list_is_assigned_a_resizable_list(self):
        class A:
            _immutable_fields_ = 'lst[*]'
        def f(n):
            a = A()
            foo = []
            foo.append(n)
            a.lst = foo

        a = self.RPythonAnnotator()
        py.test.raises(ListChangeUnallowed, a.build_types, f, [int])

    def test_can_merge_immutable_list_with_regular_list(self):
        class A:
            _immutable_fields_ = 'lst[*]'
        def foo(lst):
            pass

        def f(n):
            a = A()
            l1 = [n, 0]
            l1[1] = n+1
            a.lst = l1
            if n > 0:
                foo(a.lst)
            else:
                lst = [0]
                lst[0] = n
                foo(lst)

        a = self.RPythonAnnotator()
        a.build_types(f, [int])

        def f(n):
            a = A()
            l1 = [n, 0]
            l1[1] = n+1
            a.lst = l1
            if n > 0:
                lst = [0]
                lst[0] = n
                foo(lst)
            else:
                foo(a.lst)

        a = self.RPythonAnnotator()
        a.build_types(f, [int])

    def test_immutable_field_subclass(self):
        class Root:
            pass
        class A(Root):
            _immutable_fields_ = '_my_lst[*]'
            def __init__(self, lst):
                self._my_lst = lst
        def foo(x):
            return len(x._my_lst)

        def f(n):
            foo(A([2, n]))
            foo(Root())

        a = self.RPythonAnnotator()
        e = py.test.raises(Exception, a.build_types, f, [int])
        assert "field '_my_lst' was migrated" in str(e.value)

    def test_call_classes_with_noarg_init(self):
        class A:
            foo = 21
        class B(A):
            foo = 22
        class C(A):
            def __init__(self):
                self.foo = 42
        class D(A):
            def __init__(self):
                self.foo = 43
        def f(i):
            if i == 1:
                cls = B
            elif i == 2:
                cls = D
            else:
                cls = C
            return cls().foo
        a = self.RPythonAnnotator()
        py.test.raises(Exception, a.build_types, f, [int])

    def test_range_variable_step(self):
        def g(n):
            return range(0, 10, n)
        def f(n):
            r = g(1)    # constant step, at first
            s = g(n)    # but it becomes a variable step
            return r
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert s.listdef.listitem.range_step == 0

    def test_specialize_arg_memo(self):
        @objectmodel.specialize.memo()
        def g(n):
            return n
        @objectmodel.specialize.arg(0)
        def f(i):
            return g(i)
        def main(i):
            if i == 2:
                return f(2)
            elif i == 3:
                return f(3)
            else:
                raise NotImplementedError

        a = self.RPythonAnnotator()
        s = a.build_types(main, [int])
        assert isinstance(s, annmodel.SomeInteger)

    def test_join_none_and_nonnull(self):
        from rpython.rlib.rstring import assert_str0

        def f(i):
            a = str(i)
            a = assert_str0(a)
            return a.join([None])

        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeString)
        assert not s.can_be_None

    def test_contains_no_nul(self):
        def f(i):
            if "\0" in i:
                return None
            else:
                return i
        a = self.RPythonAnnotator()
        a.translator.config.translation.check_str_without_nul = True
        s = a.build_types(f, [annmodel.SomeString(no_nul=False)])
        assert isinstance(s, annmodel.SomeString)
        assert s.can_be_None
        assert s.no_nul

    def test_no___call__(self):
        class X(object):
            def __call__(self):
                xxx
        x = X()
        def f():
            return x
        a = self.RPythonAnnotator()
        e = py.test.raises(Exception, a.build_types, f, [])
        assert 'object with a __call__ is not RPython' in str(e.value)

    def test_os_getcwd(self):
        import os
        def fn():
            return os.getcwd()
        a = self.RPythonAnnotator()
        s = a.build_types(fn, [])
        assert isinstance(s, annmodel.SomeString)
        assert s.no_nul

    def test_os_getenv(self):
        import os
        def fn():
            return os.environ.get('PATH')
        a = self.RPythonAnnotator()
        s = a.build_types(fn, [])
        assert isinstance(s, annmodel.SomeString)
        assert s.no_nul

    def test_base_iter(self):
        class A(object):
            def __iter__(self):
                return self

        def fn():
            return iter(A())

        a = self.RPythonAnnotator()
        s = a.build_types(fn, [])
        assert isinstance(s, annmodel.SomeInstance)
        assert s.classdef.name.endswith('.A')

    def test_iter_next(self):
        class A(object):
            def __iter__(self):
                return self

            def next(self):
                return 1

        def fn():
            s = 0
            for x in A():
                s += x
            return s

        a = self.RPythonAnnotator()
        s = a.build_types(fn, [])
        assert len(a.translator.graphs) == 3 # fn, __iter__, next
        assert isinstance(s, annmodel.SomeInteger)

    def test_next_function(self):
        def fn(n):
            x = [0, 1, n]
            i = iter(x)
            return next(i) + next(i)

        a = self.RPythonAnnotator()
        s = a.build_types(fn, [int])
        assert isinstance(s, annmodel.SomeInteger)

    def test_instance_getitem(self):
        class A(object):
            def __getitem__(self, i):
                return i * i

        def fn(i):
            a = A()
            return a[i]

        a = self.RPythonAnnotator()
        s = a.build_types(fn, [int])
        assert len(a.translator.graphs) == 2 # fn, __getitem__
        assert isinstance(s, annmodel.SomeInteger)

    def test_instance_setitem(self):
        class A(object):
            def __setitem__(self, i, v):
                self.value = i * v

        def fn(i, v):
            a = A()
            a[i] = v
            return a.value

        a = self.RPythonAnnotator()
        s = a.build_types(fn, [int, int])
        assert len(a.translator.graphs) == 2 # fn, __setitem__
        assert isinstance(s, annmodel.SomeInteger)

    def test_instance_getslice(self):
        class A(object):
            def __getslice__(self, stop, start):
                return "Test"[stop:start]

        def fn():
            a = A()
            return a[0:2]

        a = self.RPythonAnnotator()
        s = a.build_types(fn, [])
        assert len(a.translator.graphs) == 2 # fn, __getslice__
        assert isinstance(s, annmodel.SomeString)

    def test_instance_setslice(self):
        class A(object):
            def __setslice__(self, stop, start, value):
                self.value = value

        def fn():
            a = A()
            a[0:2] = '00'
            return a.value

        a = self.RPythonAnnotator()
        s = a.build_types(fn, [])
        assert len(a.translator.graphs) == 2 # fn, __setslice__
        assert isinstance(s, annmodel.SomeString)

    def test_instance_len(self):
        class A(object):
            def __len__(self):
                return 0

        def fn():
            a = A()
            return len(a)

        a = self.RPythonAnnotator()
        s = a.build_types(fn, [])
        assert len(a.translator.graphs) == 2 # fn, __len__
        assert isinstance(s, annmodel.SomeInteger)

    def test_reversed(self):
        def fn(n):
            for elem in reversed([1, 2, 3, 4, 5]):
                return elem
            return n

        a = self.RPythonAnnotator()
        s = a.build_types(fn, [int])
        assert isinstance(s, annmodel.SomeInteger)

    def test_no_attr_on_common_exception_classes(self):
        for cls in [ValueError, Exception]:
            def fn():
                e = cls()
                e.foo = "bar"
            a = self.RPythonAnnotator()
            py.test.raises(Exception, a.build_types, fn, [])

    def test_lower_char(self):
        def fn(c):
            return c.lower()
        a = self.RPythonAnnotator()
        s = a.build_types(fn, [annmodel.SomeChar()])
        assert s == annmodel.SomeChar()

    def test_isinstance_double_const(self):
        class X(object):
            def _freeze_(self):
                return True

        x = X()

        def f(i):
            if i:
                x1 = x
            else:
                x1 = None
            print "hello" # this is to force the merge of blocks
            return isinstance(x1, X)

        a = self.RPythonAnnotator()
        s = a.build_types(f, [annmodel.SomeInteger()])
        assert isinstance(s, annmodel.SomeBool)

    def test_object_init(self):
        class A(object):
            pass

        class B(A):
            def __init__(self):
                A.__init__(self)

        def f():
            B()

        a = self.RPythonAnnotator()
        a.build_types(f, []) # assert did not explode

    def test_bytearray(self):
        def f():
            return bytearray("xyz")

        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeByteArray)
        assert not s.is_constant()   # never a constant!

    def test_bytearray_add(self):
        def f(a):
            return a + bytearray("xyz")

        a = self.RPythonAnnotator()
        assert isinstance(a.build_types(f, [annmodel.SomeByteArray()]),
                          annmodel.SomeByteArray)
        a = self.RPythonAnnotator()
        assert isinstance(a.build_types(f, [str]),
                          annmodel.SomeByteArray)
        a = self.RPythonAnnotator()
        assert isinstance(a.build_types(f, [annmodel.SomeChar()]),
                          annmodel.SomeByteArray)

    def test_bytearray_setitem_getitem(self):
        def f(b, i, c):
            b[i] = c
            return b[i + 1]

        a = self.RPythonAnnotator()
        assert isinstance(a.build_types(f, [annmodel.SomeByteArray(),
                                            int, int]),
                          annmodel.SomeInteger)

    def test_constant_startswith_endswith(self):
        def f():
            return "abc".startswith("ab") and "abc".endswith("bc")
        a = self.RPythonAnnotator()
        assert a.build_types(f, []).const is True

    def test_specific_attributes(self):
        class A(object):
            pass

        class B(A):
            def __init__(self, x):
                assert x >= 0
                self.x = x

        def fn(i):
            if i % 2:
                a = A()
            else:
                a = B(3)
            if i % 3:
                a.x = -3
            if isinstance(a, B):
                return a.x
            return 0

        a = self.RPythonAnnotator()
        assert not a.build_types(fn, [int]).nonneg

    def test_unionerror_attrs(self):
        def f(x):
            if x < 10:
                return 1
            else:
                return "bbb"
        a = self.RPythonAnnotator()

        with py.test.raises(annmodel.UnionError) as exc:
            a.build_types(f, [int])

        the_exc = exc.value
        s_objs = set([type(the_exc.s_obj1), type(the_exc.s_obj2)])

        assert s_objs == set([annmodel.SomeInteger, annmodel.SomeString])

    def test_unionerror_tuple_size(self):
        def f(x):
            if x < 10:
                return (1, )
            else:
                return (1, 2)
        a = self.RPythonAnnotator()

        with py.test.raises(annmodel.UnionError) as exc:
            a.build_types(f, [int])

        assert "RPython cannot unify tuples of different length: 2 versus 1" in exc.value.msg

    def test_unionerror_signedness(self):
        def f(x):
            if x < 10:
                return r_uint(99)
            else:
                return -1
        a = self.RPythonAnnotator()

        with py.test.raises(annmodel.UnionError) as exc:
            a.build_types(f, [int])

        assert ("RPython cannot prove that these integers are of the "
                "same signedness" in exc.value.msg)

    def test_unionerror_instance(self):
        class A(object): pass
        class B(object): pass

        def f(x):
            if x < 10:
                return A()
            else:
                return B()
        a = self.RPythonAnnotator()

        with py.test.raises(annmodel.UnionError) as exc:
            a.build_types(f, [int])

        assert ("RPython cannot unify instances with no common base class"
                in exc.value.msg)

    def test_unionerror_iters(self):

        def f(x):
            d = { 1 : "a", 2 : "b" }
            if x < 10:
                return d.iterkeys()
            else:
                return d.itervalues()
        a = self.RPythonAnnotator()

        with py.test.raises(annmodel.UnionError) as exc:
            a.build_types(f, [int])

        assert ("RPython cannot unify incompatible iterator variants" in
                exc.value.msg)

    def test_variable_getattr(self):
        class A(object): pass
        def f(y):
            a = A()
            return getattr(a, y)
        a = self.RPythonAnnotator()
        with py.test.raises(annmodel.AnnotatorError) as exc:
            a.build_types(f, [str])
        assert ("variable argument to getattr" in exc.value.msg)

    def test_bad_call(self):
        def f(x):
            return x()
        a = self.RPythonAnnotator()
        with py.test.raises(annmodel.AnnotatorError) as exc:
            a.build_types(f, [str])
        assert ("Cannot prove that the object is callable" in exc.value.msg)

    def test_UnionError_on_PBC(self):
        l = ['a', 1]
        def f(x):
            l.append(x)
        a = self.RPythonAnnotator()
        with py.test.raises(annmodel.UnionError) as excinfo:
            a.build_types(f, [int])
        assert 'Happened at file' in excinfo.value.source
        assert 'Known variable annotations:' in excinfo.value.source

    def test_str_format_error(self):
        def f(s, x):
            return s.format(x)
        a = self.RPythonAnnotator()
        with py.test.raises(annmodel.AnnotatorError) as exc:
            a.build_types(f, [str, str])
        assert ("format() is not RPython" in exc.value.msg)

    def test_prebuilt_ordered_dict(self):
        try:
            from collections import OrderedDict
        except ImportError:
            py.test.skip("Please upgrade to python 2.7")
        d = OrderedDict([("aa", 1)])

        def f():
            return d

        a = self.RPythonAnnotator()
        assert isinstance(a.build_types(f, []), annmodel.SomeOrderedDict)

    def test_enumerate_none(self):
        # enumerate(None) can occur as an intermediate step during a full
        # annotation, because the None will be generalized later to
        # None-or-list for example
        def f(flag):
            if flag:
                x = None
            else:
                x = [42]
            return enumerate(x).next()
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeTuple)
        assert s.items[1].const == 42

    def test_unpack_none_gets_a_blocked_block(self):
        def f(x):
            a, b = x
        a = self.RPythonAnnotator()
        py.test.raises(annmodel.AnnotatorError,
                       a.build_types, f, [annmodel.s_None])

    def test_class___name__(self):
        class Abc(object):
            pass
        def f():
            return Abc().__class__.__name__
        a = self.RPythonAnnotator()
        s = a.build_types(f, [])
        assert isinstance(s, annmodel.SomeString)

    def test_isinstance_str_1(self):
        def g():
            pass
        def f(n):
            if n > 5:
                s = "foo"
            else:
                s = None
            g()
            return isinstance(s, str)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeBool)
        assert not s.is_constant()

    def test_isinstance_str_2(self):
        def g():
            pass
        def f(n):
            if n > 5:
                s = "foo"
            else:
                s = None
            g()
            if isinstance(s, str):
                return s
            return ""
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeString)
        assert not s.can_be_none()

    def test_property_getter(self):
        class O1(object):
            def __init__(self, x):
                self._x = x
            @property
            def x(self):
                return self._x
        def f(n):
            o = O1(n)
            return o.x + getattr(o, 'x')
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        assert isinstance(s, annmodel.SomeInteger)
        op = list(graphof(a, f).iterblocks())[0].operations
        i = 0
        c = 0
        while i < len(op):
            if op[i].opname == 'getattr':
                c += 1
                assert op[i].args[1].value == 'x__getter__'
                i += 1
                assert i < len(op) and op[i].opname == 'simple_call' and \
                            op[i].args[0] == op[i - 1].result
            i += 1
        assert c == 2

    def test_property_setter(self):
        class O2(object):
            def __init__(self):
                self._x = 0
            def set_x(self, v):
                self._x = v
            x = property(fset=set_x)
        def f(n):
            o = O2()
            o.x = n
            setattr(o, 'x', n)
        a = self.RPythonAnnotator()
        s = a.build_types(f, [int])
        op = list(graphof(a, f).iterblocks())[0].operations
        i = 0
        c = 0
        while i < len(op):
            if op[i].opname == 'getattr':
                c += 1
                assert op[i].args[1].value == 'x__setter__'
                i += 1
                assert i < len(op) and op[i].opname == 'simple_call' and \
                            op[i].args[0] == op[i - 1].result and len(op[i].args) == 2
            i += 1
        assert c == 2

    def test_property_unionerr(self):
        class O1(object):
            def __init__(self, x):
                self._x = x
            @property
            def x(self):
                return self._x
        class O2(O1):
            def set_x(self, v):
                self._x = v
            x = property(fset=set_x)
        def f1(n):
            o = O2(n)
            return o.x
        def f2(n):
            o = O2(n)
            o.x = 20
        a = self.RPythonAnnotator()
        with py.test.raises(annmodel.UnionError) as exc:
            a.build_types(f1, [int])
        a = self.RPythonAnnotator()
        with py.test.raises(annmodel.UnionError) as exc:
            a.build_types(f2, [int])


def g(n):
    return [0, 1, 2, n]


def f_calls_g(n):
    total = 0
    lst = g(n)
    i = 0
    while i < len(lst):
        total += i
        i += 1
    return total

constant_unsigned_five = r_uint(5)

class Freezing:
    def _freeze_(self):
        return True
