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# -*- coding: utf-8 -*-

import ast
import numbers

from bpython.simpleeval import (
    simple_eval,
    evaluate_current_expression,
    EvaluationError,
    safe_get_attribute,
    safe_get_attribute_new_style,
)
from bpython.test import unittest
from bpython._py3compat import py3


class TestSimpleEval(unittest.TestCase):
    def assertMatchesStdlib(self, expr):
        self.assertEqual(ast.literal_eval(expr), simple_eval(expr))

    def test_matches_stdlib(self):
        """Should match the stdlib literal_eval if no names or indexing"""
        self.assertMatchesStdlib("[1]")
        self.assertMatchesStdlib("{(1,): [2,3,{}]}")

    def test_indexing(self):
        """Literals can be indexed into"""
        self.assertEqual(simple_eval("[1,2][0]"), 1)
        self.assertEqual(simple_eval("a", {"a": 1}), 1)

    def test_name_lookup(self):
        """Names can be lookup up in a namespace"""
        self.assertEqual(simple_eval("a", {"a": 1}), 1)
        self.assertEqual(simple_eval("map"), map)
        self.assertEqual(simple_eval("a[b]", {"a": {"c": 1}, "b": "c"}), 1)

    def test_allow_name_lookup(self):
        """Names can be lookup up in a namespace"""
        self.assertEqual(simple_eval("a", {"a": 1}), 1)

    def test_lookup_on_suspicious_types(self):
        class FakeDict(object):
            pass

        with self.assertRaises(ValueError):
            simple_eval("a[1]", {"a": FakeDict()})

        class TrickyDict(dict):
            def __getitem__(self, index):
                self.fail("doing key lookup isn't safe")

        with self.assertRaises(ValueError):
            simple_eval("a[1]", {"a": TrickyDict()})

        class SchrodingersDict(dict):
            def __getattribute__(inner_self, attr):
                self.fail("doing attribute lookup might have side effects")

        with self.assertRaises(ValueError):
            simple_eval("a[1]", {"a": SchrodingersDict()})

        class SchrodingersCatsDict(dict):
            def __getattr__(inner_self, attr):
                self.fail("doing attribute lookup might have side effects")

        with self.assertRaises(ValueError):
            simple_eval("a[1]", {"a": SchrodingersDict()})

    def test_operators_on_suspicious_types(self):
        class Spam(numbers.Number):
            def __add__(inner_self, other):
                self.fail("doing attribute lookup might have side effects")

        with self.assertRaises(ValueError):
            simple_eval("a + 1", {"a": Spam()})

    def test_operators_on_numbers(self):
        self.assertEqual(simple_eval("-2"), -2)
        self.assertEqual(simple_eval("1 + 1"), 2)
        self.assertEqual(simple_eval("a - 2", {"a": 1}), -1)
        with self.assertRaises(ValueError):
            simple_eval("2 * 3")
        with self.assertRaises(ValueError):
            simple_eval("2 ** 3")

    def test_function_calls_raise(self):
        with self.assertRaises(ValueError):
            simple_eval("1()")

    def test_nonexistant_names_raise(self):
        with self.assertRaises(EvaluationError):
            simple_eval("a")

    def test_attribute_access(self):
        class Foo(object):
            abc = 1

        self.assertEqual(simple_eval("foo.abc", {"foo": Foo()}), 1)


class TestEvaluateCurrentExpression(unittest.TestCase):
    def assertEvaled(self, line, value, ns=None):
        assert line.count("|") == 1
        cursor_offset = line.find("|")
        line = line.replace("|", "")
        self.assertEqual(
            evaluate_current_expression(cursor_offset, line, ns), value
        )

    def assertCannotEval(self, line, ns=None):
        assert line.count("|") == 1
        cursor_offset = line.find("|")
        line = line.replace("|", "")
        with self.assertRaises(EvaluationError):
            evaluate_current_expression(cursor_offset, line, ns)

    def test_simple(self):
        self.assertEvaled("[1].a|bc", [1])
        self.assertEvaled("[1].abc|", [1])
        self.assertEvaled("[1].|abc", [1])
        self.assertEvaled("[1]. |abc", [1])
        self.assertEvaled("[1] .|abc", [1])
        self.assertCannotEval("[1].abc |", [1])
        self.assertCannotEval("[1]. abc |", [1])
        self.assertCannotEval("[2][1].a|bc", [1])

    def test_nonsense(self):
        self.assertEvaled("!@#$ [1].a|bc", [1])
        self.assertEvaled("--- [2][0].a|bc", 2)
        self.assertCannotEval('"asdf".centered()[1].a|bc')
        self.assertEvaled('"asdf"[1].a|bc', "s")

    def test_with_namespace(self):
        self.assertEvaled("a[1].a|bc", "d", {"a": "adsf"})
        self.assertCannotEval("a[1].a|bc", {})


class A(object):
    a = "a"


class B(A):
    b = "b"


class Property(object):
    @property
    def prop(self):
        raise AssertionError("Property __get__ executed")


class Slots(object):
    __slots__ = ["s1", "s2", "s3"]

    if not py3:

        @property
        def s3(self):
            raise AssertionError("Property __get__ executed")


class SlotsSubclass(Slots):
    @property
    def s4(self):
        raise AssertionError("Property __get__ executed")


class OverriddenGetattr(object):
    def __getattr__(self, attr):
        raise AssertionError("custom __getattr__ executed")

    a = 1


class OverriddenGetattribute(object):
    def __getattribute__(self, attr):
        raise AssertionError("custom __getattribute__ executed")

    a = 1


class OverriddenMRO(object):
    def __mro__(self):
        raise AssertionError("custom mro executed")

    a = 1


member_descriptor = type(Slots.s1)


class TestSafeGetAttribute(unittest.TestCase):
    def test_lookup_on_object(self):
        a = A()
        a.x = 1
        self.assertEqual(safe_get_attribute_new_style(a, "x"), 1)
        self.assertEqual(safe_get_attribute_new_style(a, "a"), "a")
        b = B()
        b.y = 2
        self.assertEqual(safe_get_attribute_new_style(b, "y"), 2)
        self.assertEqual(safe_get_attribute_new_style(b, "a"), "a")
        self.assertEqual(safe_get_attribute_new_style(b, "b"), "b")

    def test_avoid_running_properties(self):
        p = Property()
        self.assertEqual(safe_get_attribute_new_style(p, "prop"), Property.prop)

    @unittest.skipIf(py3, "Old-style classes not in Python 3")
    def test_raises_on_old_style_class(self):
        class Old:
            pass

        with self.assertRaises(ValueError):
            safe_get_attribute_new_style(Old, "asdf")

    def test_lookup_with_slots(self):
        s = Slots()
        s.s1 = "s1"
        self.assertEqual(safe_get_attribute(s, "s1"), "s1")
        self.assertIsInstance(
            safe_get_attribute_new_style(s, "s1"), member_descriptor
        )
        with self.assertRaises(AttributeError):
            safe_get_attribute(s, "s2")
        self.assertIsInstance(
            safe_get_attribute_new_style(s, "s2"), member_descriptor
        )

    def test_lookup_on_slots_classes(self):
        sga = safe_get_attribute
        s = SlotsSubclass()
        self.assertIsInstance(sga(Slots, "s1"), member_descriptor)
        self.assertIsInstance(sga(SlotsSubclass, "s1"), member_descriptor)
        self.assertIsInstance(sga(SlotsSubclass, "s4"), property)
        self.assertIsInstance(sga(s, "s4"), property)

    @unittest.skipIf(py3, "Py 3 doesn't allow slots and prop in same class")
    def test_lookup_with_property_and_slots(self):
        sga = safe_get_attribute
        s = SlotsSubclass()
        self.assertIsInstance(sga(Slots, "s3"), property)
        self.assertEqual(safe_get_attribute(s, "s3"), Slots.__dict__["s3"])
        self.assertIsInstance(sga(SlotsSubclass, "s3"), property)

    def test_lookup_on_overridden_methods(self):
        sga = safe_get_attribute
        self.assertEqual(sga(OverriddenGetattr(), "a"), 1)
        self.assertEqual(sga(OverriddenGetattribute(), "a"), 1)
        self.assertEqual(sga(OverriddenMRO(), "a"), 1)
        with self.assertRaises(AttributeError):
            sga(OverriddenGetattr(), "b")
        with self.assertRaises(AttributeError):
            sga(OverriddenGetattribute(), "b")
        with self.assertRaises(AttributeError):
            sga(OverriddenMRO(), "b")


if __name__ == "__main__":
    unittest.main()

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