# -*- coding: utf-8 -*-
#
# Copyright (C) 2006-2009 Edgewall Software
# All rights reserved.
#
# This software is licensed as described in the file COPYING, which
# you should have received as part of this distribution. The terms
# are also available at http://genshi.edgewall.org/wiki/License.
#
# This software consists of voluntary contributions made by many
# individuals. For the exact contribution history, see the revision
# history and logs, available at http://genshi.edgewall.org/log/.

import doctest
import os
import pickle
from StringIO import StringIO
import sys
from tempfile import mkstemp
import unittest

from genshi.core import Markup
from genshi.template.base import Context
from genshi.template.eval import Expression, Suite, Undefined, UndefinedError, \
                                 UNDEFINED


class ExpressionTestCase(unittest.TestCase):

    def test_eq(self):
        expr = Expression('x,y')
        self.assertEqual(expr, Expression('x,y'))
        self.assertNotEqual(expr, Expression('y, x'))

    def test_hash(self):
        expr = Expression('x,y')
        self.assertEqual(hash(expr), hash(Expression('x,y')))
        self.assertNotEqual(hash(expr), hash(Expression('y, x')))

    def test_pickle(self):
        expr = Expression('1 < 2')
        buf = StringIO()
        pickle.dump(expr, buf, 2)
        buf.seek(0)
        unpickled = pickle.load(buf)
        assert unpickled.evaluate({}) is True

    def test_name_lookup(self):
        self.assertEqual('bar', Expression('foo').evaluate({'foo': 'bar'}))
        self.assertEqual(id, Expression('id').evaluate({}))
        self.assertEqual('bar', Expression('id').evaluate({'id': 'bar'}))
        self.assertEqual(None, Expression('id').evaluate({'id': None}))

    def test_builtins(self):
        expr = Expression('Markup')
        self.assertEqual(expr.evaluate({}), Markup)

    def test_str_literal(self):
        self.assertEqual('foo', Expression('"foo"').evaluate({}))
        self.assertEqual('foo', Expression('"""foo"""').evaluate({}))
        self.assertEqual('foo', Expression("'foo'").evaluate({}))
        self.assertEqual('foo', Expression("'''foo'''").evaluate({}))
        self.assertEqual('foo', Expression("u'foo'").evaluate({}))
        self.assertEqual('foo', Expression("r'foo'").evaluate({}))

    def test_str_literal_non_ascii(self):
        expr = Expression(u"u'\xfe'")
        self.assertEqual(u'þ', expr.evaluate({}))
        expr = Expression("u'\xfe'")
        self.assertEqual(u'þ', expr.evaluate({}))
        expr = Expression("'\xc3\xbe'")
        self.assertEqual(u'þ', expr.evaluate({}))

    def test_num_literal(self):
        self.assertEqual(42, Expression("42").evaluate({}))
        self.assertEqual(42L, Expression("42L").evaluate({}))
        self.assertEqual(.42, Expression(".42").evaluate({}))
        self.assertEqual(07, Expression("07").evaluate({}))
        self.assertEqual(0xF2, Expression("0xF2").evaluate({}))
        self.assertEqual(0XF2, Expression("0XF2").evaluate({}))

    def test_dict_literal(self):
        self.assertEqual({}, Expression("{}").evaluate({}))
        self.assertEqual({'key': True},
                         Expression("{'key': value}").evaluate({'value': True}))

    def test_list_literal(self):
        self.assertEqual([], Expression("[]").evaluate({}))
        self.assertEqual([1, 2, 3], Expression("[1, 2, 3]").evaluate({}))
        self.assertEqual([True],
                         Expression("[value]").evaluate({'value': True}))

    def test_tuple_literal(self):
        self.assertEqual((), Expression("()").evaluate({}))
        self.assertEqual((1, 2, 3), Expression("(1, 2, 3)").evaluate({}))
        self.assertEqual((True,),
                         Expression("(value,)").evaluate({'value': True}))

    def test_unaryop_pos(self):
        self.assertEqual(1, Expression("+1").evaluate({}))
        self.assertEqual(1, Expression("+x").evaluate({'x': 1}))

    def test_unaryop_neg(self):
        self.assertEqual(-1, Expression("-1").evaluate({}))
        self.assertEqual(-1, Expression("-x").evaluate({'x': 1}))

    def test_unaryop_not(self):
        self.assertEqual(False, Expression("not True").evaluate({}))
        self.assertEqual(False, Expression("not x").evaluate({'x': True}))

    def test_unaryop_inv(self):
        self.assertEqual(-2, Expression("~1").evaluate({}))
        self.assertEqual(-2, Expression("~x").evaluate({'x': 1}))

    def test_binop_add(self):
        self.assertEqual(3, Expression("2 + 1").evaluate({}))
        self.assertEqual(3, Expression("x + y").evaluate({'x': 2, 'y': 1}))

    def test_binop_sub(self):
        self.assertEqual(1, Expression("2 - 1").evaluate({}))
        self.assertEqual(1, Expression("x - y").evaluate({'x': 1, 'y': 1}))

    def test_binop_sub(self):
        self.assertEqual(1, Expression("2 - 1").evaluate({}))
        self.assertEqual(1, Expression("x - y").evaluate({'x': 2, 'y': 1}))

    def test_binop_mul(self):
        self.assertEqual(4, Expression("2 * 2").evaluate({}))
        self.assertEqual(4, Expression("x * y").evaluate({'x': 2, 'y': 2}))

    def test_binop_pow(self):
        self.assertEqual(4, Expression("2 ** 2").evaluate({}))
        self.assertEqual(4, Expression("x ** y").evaluate({'x': 2, 'y': 2}))

    def test_binop_div(self):
        self.assertEqual(2, Expression("4 / 2").evaluate({}))
        self.assertEqual(2, Expression("x / y").evaluate({'x': 4, 'y': 2}))

    def test_binop_floordiv(self):
        self.assertEqual(1, Expression("3 // 2").evaluate({}))
        self.assertEqual(1, Expression("x // y").evaluate({'x': 3, 'y': 2}))

    def test_binop_mod(self):
        self.assertEqual(1, Expression("3 % 2").evaluate({}))
        self.assertEqual(1, Expression("x % y").evaluate({'x': 3, 'y': 2}))

    def test_binop_and(self):
        self.assertEqual(0, Expression("1 & 0").evaluate({}))
        self.assertEqual(0, Expression("x & y").evaluate({'x': 1, 'y': 0}))

    def test_binop_or(self):
        self.assertEqual(1, Expression("1 | 0").evaluate({}))
        self.assertEqual(1, Expression("x | y").evaluate({'x': 1, 'y': 0}))

    def test_binop_xor(self):
        self.assertEqual(1, Expression("1 ^ 0").evaluate({}))
        self.assertEqual(1, Expression("x ^ y").evaluate({'x': 1, 'y': 0}))

    def test_binop_contains(self):
        self.assertEqual(True, Expression("1 in (1, 2, 3)").evaluate({}))
        self.assertEqual(True, Expression("x in y").evaluate({'x': 1,
                                                              'y': (1, 2, 3)}))

    def test_binop_not_contains(self):
        self.assertEqual(True, Expression("4 not in (1, 2, 3)").evaluate({}))
        self.assertEqual(True, Expression("x not in y").evaluate({'x': 4,
                                                                  'y': (1, 2, 3)}))

    def test_binop_is(self):
        self.assertEqual(True, Expression("1 is 1").evaluate({}))
        self.assertEqual(True, Expression("x is y").evaluate({'x': 1, 'y': 1}))
        self.assertEqual(False, Expression("1 is 2").evaluate({}))
        self.assertEqual(False, Expression("x is y").evaluate({'x': 1, 'y': 2}))

    def test_binop_is_not(self):
        self.assertEqual(True, Expression("1 is not 2").evaluate({}))
        self.assertEqual(True, Expression("x is not y").evaluate({'x': 1,
                                                                  'y': 2}))
        self.assertEqual(False, Expression("1 is not 1").evaluate({}))
        self.assertEqual(False, Expression("x is not y").evaluate({'x': 1,
                                                                   'y': 1}))

    def test_boolop_and(self):
        self.assertEqual(False, Expression("True and False").evaluate({}))
        self.assertEqual(False, Expression("x and y").evaluate({'x': True,
                                                                'y': False}))

    def test_boolop_or(self):
        self.assertEqual(True, Expression("True or False").evaluate({}))
        self.assertEqual(True, Expression("x or y").evaluate({'x': True,
                                                              'y': False}))

    def test_compare_eq(self):
        self.assertEqual(True, Expression("1 == 1").evaluate({}))
        self.assertEqual(True, Expression("x == y").evaluate({'x': 1, 'y': 1}))

    def test_compare_ne(self):
        self.assertEqual(False, Expression("1 != 1").evaluate({}))
        self.assertEqual(False, Expression("x != y").evaluate({'x': 1, 'y': 1}))
        if sys.version < '3':
            self.assertEqual(False, Expression("1 <> 1").evaluate({}))
            self.assertEqual(False, Expression("x <> y").evaluate({'x': 1, 'y': 1}))

    def test_compare_lt(self):
        self.assertEqual(True, Expression("1 < 2").evaluate({}))
        self.assertEqual(True, Expression("x < y").evaluate({'x': 1, 'y': 2}))

    def test_compare_le(self):
        self.assertEqual(True, Expression("1 <= 1").evaluate({}))
        self.assertEqual(True, Expression("x <= y").evaluate({'x': 1, 'y': 1}))

    def test_compare_gt(self):
        self.assertEqual(True, Expression("2 > 1").evaluate({}))
        self.assertEqual(True, Expression("x > y").evaluate({'x': 2, 'y': 1}))

    def test_compare_ge(self):
        self.assertEqual(True, Expression("1 >= 1").evaluate({}))
        self.assertEqual(True, Expression("x >= y").evaluate({'x': 1, 'y': 1}))

    def test_compare_multi(self):
        self.assertEqual(True, Expression("1 != 3 == 3").evaluate({}))
        self.assertEqual(True, Expression("x != y == y").evaluate({'x': 1,
                                                                   'y': 3}))

    def test_call_function(self):
        self.assertEqual(42, Expression("foo()").evaluate({'foo': lambda: 42}))
        data = {'foo': 'bar'}
        self.assertEqual('BAR', Expression("foo.upper()").evaluate(data))
        data = {'foo': {'bar': range(42)}}
        self.assertEqual(42, Expression("len(foo.bar)").evaluate(data))

    def test_call_keywords(self):
        self.assertEqual(42, Expression("foo(x=bar)").evaluate({'foo': lambda x: x,
                                                                'bar': 42}))

    def test_call_star_args(self):
        self.assertEqual(42, Expression("foo(*bar)").evaluate({'foo': lambda x: x,
                                                               'bar': [42]}))

    def test_call_dstar_args(self):
        def foo(x):
            return x
        expr = Expression("foo(**bar)")
        self.assertEqual(42, expr.evaluate({'foo': foo, 'bar': {"x": 42}}))

    def test_lambda(self):
        data = {'items': range(5)}
        expr = Expression("filter(lambda x: x > 2, items)")
        self.assertEqual([3, 4], expr.evaluate(data))

    def test_list_comprehension(self):
        expr = Expression("[n for n in numbers if n < 2]")
        self.assertEqual([0, 1], expr.evaluate({'numbers': range(5)}))

        expr = Expression("[(i, n + 1) for i, n in enumerate(numbers)]")
        self.assertEqual([(0, 1), (1, 2), (2, 3), (3, 4), (4, 5)],
                         expr.evaluate({'numbers': range(5)}))

        expr = Expression("[offset + n for n in numbers]")
        self.assertEqual([2, 3, 4, 5, 6],
                         expr.evaluate({'numbers': range(5), 'offset': 2}))

        expr = Expression("[n for group in groups for n in group]")
        self.assertEqual([0, 1, 0, 1, 2],
                         expr.evaluate({'groups': [range(2), range(3)]}))

        expr = Expression("[(a, b) for a in x for b in y]")
        self.assertEqual([('x0', 'y0'), ('x0', 'y1'), ('x1', 'y0'), ('x1', 'y1')],
                         expr.evaluate({'x': ['x0', 'x1'], 'y': ['y0', 'y1']}))

    def test_list_comprehension_with_getattr(self):
        items = [{'name': 'a', 'value': 1}, {'name': 'b', 'value': 2}]
        expr = Expression("[i.name for i in items if i.value > 1]")
        self.assertEqual(['b'], expr.evaluate({'items': items}))

    def test_list_comprehension_with_getitem(self):
        items = [{'name': 'a', 'value': 1}, {'name': 'b', 'value': 2}]
        expr = Expression("[i['name'] for i in items if i['value'] > 1]")
        self.assertEqual(['b'], expr.evaluate({'items': items}))

    def test_generator_expression(self):
        expr = Expression("list(n for n in numbers if n < 2)")
        self.assertEqual([0, 1], expr.evaluate({'numbers': range(5)}))

        expr = Expression("list((i, n + 1) for i, n in enumerate(numbers))")
        self.assertEqual([(0, 1), (1, 2), (2, 3), (3, 4), (4, 5)],
                         expr.evaluate({'numbers': range(5)}))

        expr = Expression("list(offset + n for n in numbers)")
        self.assertEqual([2, 3, 4, 5, 6],
                         expr.evaluate({'numbers': range(5), 'offset': 2}))

        expr = Expression("list(n for group in groups for n in group)")
        self.assertEqual([0, 1, 0, 1, 2],
                         expr.evaluate({'groups': [range(2), range(3)]}))

        expr = Expression("list((a, b) for a in x for b in y)")
        self.assertEqual([('x0', 'y0'), ('x0', 'y1'), ('x1', 'y0'), ('x1', 'y1')],
                         expr.evaluate({'x': ['x0', 'x1'], 'y': ['y0', 'y1']}))

    def test_generator_expression_with_getattr(self):
        items = [{'name': 'a', 'value': 1}, {'name': 'b', 'value': 2}]
        expr = Expression("list(i.name for i in items if i.value > 1)")
        self.assertEqual(['b'], expr.evaluate({'items': items}))

    def test_generator_expression_with_getitem(self):
        items = [{'name': 'a', 'value': 1}, {'name': 'b', 'value': 2}]
        expr = Expression("list(i['name'] for i in items if i['value'] > 1)")
        self.assertEqual(['b'], expr.evaluate({'items': items}))

    if sys.version_info >= (2, 5):
        def test_conditional_expression(self):
            expr = Expression("'T' if foo else 'F'")
            self.assertEqual('T', expr.evaluate({'foo': True}))
            self.assertEqual('F', expr.evaluate({'foo': False}))

    def test_slice(self):
        expr = Expression("numbers[0:2]")
        self.assertEqual([0, 1], expr.evaluate({'numbers': range(5)}))

    def test_slice_with_vars(self):
        expr = Expression("numbers[start:end]")
        self.assertEqual([0, 1], expr.evaluate({'numbers': range(5), 'start': 0,
                                                'end': 2}))

    def test_slice_copy(self):
        expr = Expression("numbers[:]")
        self.assertEqual([0, 1, 2, 3, 4], expr.evaluate({'numbers': range(5)}))

    def test_slice_stride(self):
        expr = Expression("numbers[::stride]")
        self.assertEqual([0, 2, 4], expr.evaluate({'numbers': range(5),
                                                   'stride': 2}))

    def test_slice_negative_start(self):
        expr = Expression("numbers[-1:]")
        self.assertEqual([4], expr.evaluate({'numbers': range(5)}))

    def test_slice_negative_end(self):
        expr = Expression("numbers[:-1]")
        self.assertEqual([0, 1, 2, 3], expr.evaluate({'numbers': range(5)}))

    def test_access_undefined(self):
        expr = Expression("nothing", filename='index.html', lineno=50,
                          lookup='lenient')
        retval = expr.evaluate({})
        assert isinstance(retval, Undefined)
        self.assertEqual('nothing', retval._name)
        assert retval._owner is UNDEFINED

    def test_getattr_undefined(self):
        class Something(object):
            def __repr__(self):
                return '<Something>'
        something = Something()
        expr = Expression('something.nil', filename='index.html', lineno=50,
                          lookup='lenient')
        retval = expr.evaluate({'something': something})
        assert isinstance(retval, Undefined)
        self.assertEqual('nil', retval._name)
        assert retval._owner is something

    def test_getattr_exception(self):
        class Something(object):
            def prop_a(self):
                raise NotImplementedError
            prop_a = property(prop_a)
            def prop_b(self):
                raise AttributeError
            prop_b = property(prop_b)
        self.assertRaises(NotImplementedError,
                          Expression('s.prop_a').evaluate, {'s': Something()})
        self.assertRaises(AttributeError,
                          Expression('s.prop_b').evaluate, {'s': Something()})

    def test_getitem_undefined_string(self):
        class Something(object):
            def __repr__(self):
                return '<Something>'
        something = Something()
        expr = Expression('something["nil"]', filename='index.html', lineno=50,
                          lookup='lenient')
        retval = expr.evaluate({'something': something})
        assert isinstance(retval, Undefined)
        self.assertEqual('nil', retval._name)
        assert retval._owner is something

    def test_getitem_exception(self):
        class Something(object):
            def __getitem__(self, key):
                raise NotImplementedError
        self.assertRaises(NotImplementedError,
                          Expression('s["foo"]').evaluate, {'s': Something()})

    def test_error_access_undefined(self):
        expr = Expression("nothing", filename='index.html', lineno=50,
                          lookup='strict')
        try:
            expr.evaluate({})
            self.fail('Expected UndefinedError')
        except UndefinedError, e:
            exc_type, exc_value, exc_traceback = sys.exc_info()
            frame = exc_traceback.tb_next
            frames = []
            while frame.tb_next:
                frame = frame.tb_next
                frames.append(frame)
            self.assertEqual('"nothing" not defined', str(e))
            self.assertEqual("<Expression 'nothing'>",
                             frames[-3].tb_frame.f_code.co_name)
            self.assertEqual('index.html',
                             frames[-3].tb_frame.f_code.co_filename)
            self.assertEqual(50, frames[-3].tb_lineno)

    def test_error_getattr_undefined(self):
        class Something(object):
            def __repr__(self):
                return '<Something>'
        expr = Expression('something.nil', filename='index.html', lineno=50,
                          lookup='strict')
        try:
            expr.evaluate({'something': Something()})
            self.fail('Expected UndefinedError')
        except UndefinedError, e:
            self.assertEqual('<Something> has no member named "nil"', str(e))
            exc_type, exc_value, exc_traceback = sys.exc_info()
            search_string = "<Expression 'something.nil'>"
            frame = exc_traceback.tb_next
            while frame.tb_next:
                frame = frame.tb_next
                code = frame.tb_frame.f_code
                if code.co_name == search_string:
                    break
            else:
                self.fail("never found the frame I was looking for")
            self.assertEqual('index.html', code.co_filename)
            self.assertEqual(50, frame.tb_lineno)

    def test_error_getitem_undefined_string(self):
        class Something(object):
            def __repr__(self):
                return '<Something>'
        expr = Expression('something["nil"]', filename='index.html', lineno=50,
                          lookup='strict')
        try:
            expr.evaluate({'something': Something()})
            self.fail('Expected UndefinedError')
        except UndefinedError, e:
            self.assertEqual('<Something> has no member named "nil"', str(e))
            exc_type, exc_value, exc_traceback = sys.exc_info()
            search_string = '''<Expression 'something["nil"]'>'''
            frame = exc_traceback.tb_next
            while frame.tb_next:
                frame = frame.tb_next
                code = frame.tb_frame.f_code
                if code.co_name == search_string:
                    break
            else:
                self.fail("never found the frame I was looking for")
            self.assertEqual('index.html', code.co_filename)
            self.assertEqual(50, frame.tb_lineno)


class SuiteTestCase(unittest.TestCase):

    def test_pickle(self):
        suite = Suite('foo = 42')
        buf = StringIO()
        pickle.dump(suite, buf, 2)
        buf.seek(0)
        unpickled = pickle.load(buf)
        data = {}
        unpickled.execute(data)
        self.assertEqual(42, data['foo'])

    def test_internal_shadowing(self):
        # The context itself is stored in the global execution scope of a suite
        # It used to get stored under the name 'data', which meant the
        # following test would fail, as the user defined 'data' variable
        # shadowed the Genshi one. We now use the name '__data__' to avoid
        # conflicts
        suite = Suite("""data = []
bar = foo
""")
        data = {'foo': 42}
        suite.execute(data)
        self.assertEqual(42, data['bar'])

    def test_assign(self):
        suite = Suite("foo = 42")
        data = {}
        suite.execute(data)
        self.assertEqual(42, data['foo'])

    def test_def(self):
        suite = Suite("def donothing(): pass")
        data = {}
        suite.execute(data)
        assert 'donothing' in data
        self.assertEqual(None, data['donothing']())

    def test_def_with_multiple_statements(self):
        suite = Suite("""
def donothing():
    if True:
        return foo
""")
        data = {'foo': 'bar'}
        suite.execute(data)
        assert 'donothing' in data
        self.assertEqual('bar', data['donothing']())

    def test_def_using_nonlocal(self):
        suite = Suite("""
values = []
def add(value):
    if value not in values:
        values.append(value)
add('foo')
add('bar')
""")
        data = {}
        suite.execute(data)
        self.assertEqual(['foo', 'bar'], data['values'])

    def test_def_some_defaults(self):
        suite = Suite("""
def difference(v1, v2=10):
    return v1 - v2
x = difference(20, 19)
y = difference(20)
""")
        data = {}
        suite.execute(data)
        self.assertEqual(1, data['x'])
        self.assertEqual(10, data['y'])

    def test_def_all_defaults(self):
        suite = Suite("""
def difference(v1=100, v2=10):
    return v1 - v2
x = difference(20, 19)
y = difference(20)
z = difference()
""")
        data = {}
        suite.execute(data)
        self.assertEqual(1, data['x'])
        self.assertEqual(10, data['y'])
        self.assertEqual(90, data['z'])

    def test_def_vararg(self):
        suite = Suite("""
def mysum(*others):
    rv = 0
    for n in others:
        rv = rv + n
    return rv
x = mysum(1, 2, 3)
""")
        data = {}
        suite.execute(data)
        self.assertEqual(6, data['x'])

    def test_def_kwargs(self):
        suite = Suite("""
def smash(**kw):
    return [''.join(i) for i in kw.items()]
x = smash(foo='abc', bar='def')
""")
        data = {}
        suite.execute(data)
        self.assertEqual(['fooabc', 'bardef'], data['x'])

    def test_def_nested(self):
        suite = Suite("""
def doit():
    values = []
    def add(value):
        if value not in values:
            values.append(value)
    add('foo')
    add('bar')
    return values
x = doit()
""")
        data = {}
        suite.execute(data)
        self.assertEqual(['foo', 'bar'], data['x'])

    def test_def_with_decorator(self):
        suite = Suite("""
def lower(fun):
    return lambda: fun().lower()

@lower
def say_hi():
    return 'Hi!'

result = say_hi()
""")
        data = {}
        suite.execute(data)
        self.assertEqual('hi!', data['result'])

    def test_delete(self):
        suite = Suite("""foo = 42
del foo
""")
        data = {}
        suite.execute(data)
        assert 'foo' not in data

    def test_class(self):
        suite = Suite("class plain(object): pass")
        data = {}
        suite.execute(data)
        assert 'plain' in data

    def test_class_in_def(self):
        suite = Suite("""
def create():
    class Foobar(object):
        def __str__(self):
            return 'foobar'
    return Foobar()
x = create()
""")
        data = {}
        suite.execute(data)
        self.assertEqual('foobar', str(data['x']))

    def test_class_with_methods(self):
        suite = Suite("""class plain(object):
    def donothing():
        pass
""")
        data = {}
        suite.execute(data)
        assert 'plain' in data

    def test_import(self):
        suite = Suite("from itertools import ifilter")
        data = {}
        suite.execute(data)
        assert 'ifilter' in data

    def test_import_star(self):
        suite = Suite("from itertools import *")
        data = Context()
        suite.execute(data)
        assert 'ifilter' in data

    def test_import_in_def(self):
        suite = Suite("""def fun():
    from itertools import ifilter
    return ifilter(None, range(3))
""")
        data = Context()
        suite.execute(data)
        assert 'ifilter' not in data
        self.assertEqual([1, 2], list(data['fun']()))

    def test_for(self):
        suite = Suite("""x = []
for i in range(3):
    x.append(i**2)
""")
        data = {}
        suite.execute(data)
        self.assertEqual([0, 1, 4], data['x'])

    def test_for_in_def(self):
        suite = Suite("""def loop():
    for i in range(10):
        if i == 5:
            break
    return i
""")
        data = {}
        suite.execute(data)
        assert 'loop' in data
        self.assertEqual(5, data['loop']())

    def test_if(self):
        suite = Suite("""if foo == 42:
    x = True
""")
        data = {'foo': 42}
        suite.execute(data)
        self.assertEqual(True, data['x'])

    def test_raise(self):
        suite = Suite("""raise NotImplementedError""")
        self.assertRaises(NotImplementedError, suite.execute, {})

    def test_try_except(self):
        suite = Suite("""try:
    import somemod
except ImportError:
    somemod = None
else:
    somemod.dosth()""")
        data = {}
        suite.execute(data)
        self.assertEqual(None, data['somemod'])

    def test_finally(self):
        suite = Suite("""try:
    x = 2
finally:
    x = None
""")
        data = {}
        suite.execute(data)
        self.assertEqual(None, data['x'])

    def test_while_break(self):
        suite = Suite("""x = 0
while x < 5:
    x += step
    if x == 4:
        break
""")
        data = {'step': 2}
        suite.execute(data)
        self.assertEqual(4, data['x'])

    def test_augmented_attribute_assignment(self):
        suite = Suite("d['k'] += 42")
        d = {"k": 1}
        suite.execute({"d": d})
        self.assertEqual(43, d["k"])

    def test_local_augmented_assign(self):
        Suite("x = 1; x += 42; assert x == 43").execute({})

    def test_augmented_assign_in_def(self):
        d = {}
        Suite("""def foo():
    i = 1
    i += 1
    return i
x = foo()""").execute(d)
        self.assertEqual(2, d['x'])

    def test_augmented_assign_in_loop_in_def(self):
        d = {}
        Suite("""def foo():
    i = 0
    for n in range(5):
        i += n
    return i
x = foo()""").execute(d)
        self.assertEqual(10, d['x'])

    def test_assign_in_list(self):
        suite = Suite("[d['k']] = 'foo',; assert d['k'] == 'foo'")
        d = {"k": "bar"}
        suite.execute({"d": d})
        self.assertEqual("foo", d["k"])

    def test_exec(self):
        suite = Suite("x = 1; exec d['k']; assert x == 42, x")
        suite.execute({"d": {"k": "x = 42"}})

    def test_return(self):
        suite = Suite("""
def f():
    return v

assert f() == 42
""")
        suite.execute({"v": 42})

    def test_assign_to_dict_item(self):
        suite = Suite("d['k'] = 'foo'")
        data = {'d': {}}
        suite.execute(data)
        self.assertEqual('foo', data['d']['k'])

    def test_assign_to_attribute(self):
        class Something(object): pass
        something = Something()
        suite = Suite("obj.attr = 'foo'")
        data = {"obj": something}
        suite.execute(data)
        self.assertEqual('foo', something.attr)

    def test_delattr(self):
        class Something(object):
            def __init__(self):
                self.attr = 'foo'
        obj = Something()
        Suite("del obj.attr").execute({'obj': obj})
        self.failIf(hasattr(obj, 'attr'))

    def test_delitem(self):
        d = {'k': 'foo'}
        Suite("del d['k']").execute({'d': d})
        self.failIf('k' in d, repr(d))

    if sys.version_info >= (2, 5):
        def test_with_statement(self):
            fd, path = mkstemp()
            f = os.fdopen(fd, "w")
            try:
                f.write('foo\nbar\n')
                f.seek(0)
                f.close()

                d = {'path': path}
                suite = Suite("""from __future__ import with_statement
lines = []
with open(path) as file:
    for line in file:
        lines.append(line)
""")
                suite.execute(d)
                self.assertEqual(['foo\n', 'bar\n'], d['lines'])
            finally:
                os.remove(path)

        def test_yield_expression(self):
            d = {}
            suite = Suite("""results = []
def counter(maximum):
    i = 0
    while i < maximum:
        val = (yield i)
        if val is not None:
            i = val
        else:
            i += 1
it = counter(5)
results.append(it.next())
results.append(it.send(3))
results.append(it.next())
""")
            suite.execute(d)
            self.assertEqual([0, 3, 4], d['results'])


def suite():
    suite = unittest.TestSuite()
    suite.addTest(doctest.DocTestSuite(Expression.__module__))
    suite.addTest(unittest.makeSuite(ExpressionTestCase, 'test'))
    suite.addTest(unittest.makeSuite(SuiteTestCase, 'test'))
    return suite

if __name__ == '__main__':
    unittest.main(defaultTest='suite')