# Deliberately use "from dataclasses import *".  Every name in __all__
# is tested, so they all must be present.  This is a way to catch
# missing ones.

from dataclasses import *

import pickle
import inspect
import builtins
import unittest
from unittest.mock import Mock
from typing import ClassVar, Any, List, Union, Tuple, Dict, Generic, TypeVar, Optional
from typing import get_type_hints
from collections import deque, OrderedDict, namedtuple
from functools import total_ordering

import typing       # Needed for the string "typing.ClassVar[int]" to work as an annotation.
import dataclasses  # Needed for the string "dataclasses.InitVar[int]" to work as an annotation.

# Just any custom exception we can catch.
class CustomError(Exception): pass

class TestCase(unittest.TestCase):
    def test_no_fields(self):
        @dataclass
        class C:
            pass

        o = C()
        self.assertEqual(len(fields(C)), 0)

    def test_no_fields_but_member_variable(self):
        @dataclass
        class C:
            i = 0

        o = C()
        self.assertEqual(len(fields(C)), 0)

    def test_one_field_no_default(self):
        @dataclass
        class C:
            x: int

        o = C(42)
        self.assertEqual(o.x, 42)

    def test_field_default_default_factory_error(self):
        msg = "cannot specify both default and default_factory"
        with self.assertRaisesRegex(ValueError, msg):
            @dataclass
            class C:
                x: int = field(default=1, default_factory=int)

    def test_field_repr(self):
        int_field = field(default=1, init=True, repr=False)
        int_field.name = "id"
        repr_output = repr(int_field)
        expected_output = "Field(name='id',type=None," \
                           f"default=1,default_factory={MISSING!r}," \
                           "init=True,repr=False,hash=None," \
                           "compare=True,metadata=mappingproxy({})," \
                           "_field_type=None)"

        self.assertEqual(repr_output, expected_output)

    def test_named_init_params(self):
        @dataclass
        class C:
            x: int

        o = C(x=32)
        self.assertEqual(o.x, 32)

    def test_two_fields_one_default(self):
        @dataclass
        class C:
            x: int
            y: int = 0

        o = C(3)
        self.assertEqual((o.x, o.y), (3, 0))

        # Non-defaults following defaults.
        with self.assertRaisesRegex(TypeError,
                                    "non-default argument 'y' follows "
                                    "default argument"):
            @dataclass
            class C:
                x: int = 0
                y: int

        # A derived class adds a non-default field after a default one.
        with self.assertRaisesRegex(TypeError,
                                    "non-default argument 'y' follows "
                                    "default argument"):
            @dataclass
            class B:
                x: int = 0

            @dataclass
            class C(B):
                y: int

        # Override a base class field and add a default to
        #  a field which didn't use to have a default.
        with self.assertRaisesRegex(TypeError,
                                    "non-default argument 'y' follows "
                                    "default argument"):
            @dataclass
            class B:
                x: int
                y: int

            @dataclass
            class C(B):
                x: int = 0

    def test_overwrite_hash(self):
        # Test that declaring this class isn't an error.  It should
        #  use the user-provided __hash__.
        @dataclass(frozen=True)
        class C:
            x: int
            def __hash__(self):
                return 301
        self.assertEqual(hash(C(100)), 301)

        # Test that declaring this class isn't an error.  It should
        #  use the generated __hash__.
        @dataclass(frozen=True)
        class C:
            x: int
            def __eq__(self, other):
                return False
        self.assertEqual(hash(C(100)), hash((100,)))

        # But this one should generate an exception, because with
        #  unsafe_hash=True, it's an error to have a __hash__ defined.
        with self.assertRaisesRegex(TypeError,
                                    'Cannot overwrite attribute __hash__'):
            @dataclass(unsafe_hash=True)
            class C:
                def __hash__(self):
                    pass

        # Creating this class should not generate an exception,
        #  because even though __hash__ exists before @dataclass is
        #  called, (due to __eq__ being defined), since it's None
        #  that's okay.
        @dataclass(unsafe_hash=True)
        class C:
            x: int
            def __eq__(self):
                pass
        # The generated hash function works as we'd expect.
        self.assertEqual(hash(C(10)), hash((10,)))

        # Creating this class should generate an exception, because
        #  __hash__ exists and is not None, which it would be if it
        #  had been auto-generated due to __eq__ being defined.
        with self.assertRaisesRegex(TypeError,
                                    'Cannot overwrite attribute __hash__'):
            @dataclass(unsafe_hash=True)
            class C:
                x: int
                def __eq__(self):
                    pass
                def __hash__(self):
                    pass

    def test_overwrite_fields_in_derived_class(self):
        # Note that x from C1 replaces x in Base, but the order remains
        #  the same as defined in Base.
        @dataclass
        class Base:
            x: Any = 15.0
            y: int = 0

        @dataclass
        class C1(Base):
            z: int = 10
            x: int = 15

        o = Base()
        self.assertEqual(repr(o), 'TestCase.test_overwrite_fields_in_derived_class.<locals>.Base(x=15.0, y=0)')

        o = C1()
        self.assertEqual(repr(o), 'TestCase.test_overwrite_fields_in_derived_class.<locals>.C1(x=15, y=0, z=10)')

        o = C1(x=5)
        self.assertEqual(repr(o), 'TestCase.test_overwrite_fields_in_derived_class.<locals>.C1(x=5, y=0, z=10)')

    def test_field_named_self(self):
        @dataclass
        class C:
            self: str
        c=C('foo')
        self.assertEqual(c.self, 'foo')

        # Make sure the first parameter is not named 'self'.
        sig = inspect.signature(C.__init__)
        first = next(iter(sig.parameters))
        self.assertNotEqual('self', first)

        # But we do use 'self' if no field named self.
        @dataclass
        class C:
            selfx: str

        # Make sure the first parameter is named 'self'.
        sig = inspect.signature(C.__init__)
        first = next(iter(sig.parameters))
        self.assertEqual('self', first)

    def test_field_named_object(self):
        @dataclass
        class C:
            object: str
        c = C('foo')
        self.assertEqual(c.object, 'foo')

    def test_field_named_object_frozen(self):
        @dataclass(frozen=True)
        class C:
            object: str
        c = C('foo')
        self.assertEqual(c.object, 'foo')

    def test_field_named_like_builtin(self):
        # Attribute names can shadow built-in names
        # since code generation is used.
        # Ensure that this is not happening.
        exclusions = {'None', 'True', 'False'}
        builtins_names = sorted(
            b for b in builtins.__dict__.keys()
            if not b.startswith('__') and b not in exclusions
        )
        attributes = [(name, str) for name in builtins_names]
        C = make_dataclass('C', attributes)

        c = C(*[name for name in builtins_names])

        for name in builtins_names:
            self.assertEqual(getattr(c, name), name)

    def test_field_named_like_builtin_frozen(self):
        # Attribute names can shadow built-in names
        # since code generation is used.
        # Ensure that this is not happening
        # for frozen data classes.
        exclusions = {'None', 'True', 'False'}
        builtins_names = sorted(
            b for b in builtins.__dict__.keys()
            if not b.startswith('__') and b not in exclusions
        )
        attributes = [(name, str) for name in builtins_names]
        C = make_dataclass('C', attributes, frozen=True)

        c = C(*[name for name in builtins_names])

        for name in builtins_names:
            self.assertEqual(getattr(c, name), name)

    def test_0_field_compare(self):
        # Ensure that order=False is the default.
        @dataclass
        class C0:
            pass

        @dataclass(order=False)
        class C1:
            pass

        for cls in [C0, C1]:
            with self.subTest(cls=cls):
                self.assertEqual(cls(), cls())
                for idx, fn in enumerate([lambda a, b: a < b,
                                          lambda a, b: a <= b,
                                          lambda a, b: a > b,
                                          lambda a, b: a >= b]):
                    with self.subTest(idx=idx):
                        with self.assertRaisesRegex(TypeError,
                                                    f"not supported between instances of '{cls.__name__}' and '{cls.__name__}'"):
                            fn(cls(), cls())

        @dataclass(order=True)
        class C:
            pass
        self.assertLessEqual(C(), C())
        self.assertGreaterEqual(C(), C())

    def test_1_field_compare(self):
        # Ensure that order=False is the default.
        @dataclass
        class C0:
            x: int

        @dataclass(order=False)
        class C1:
            x: int

        for cls in [C0, C1]:
            with self.subTest(cls=cls):
                self.assertEqual(cls(1), cls(1))
                self.assertNotEqual(cls(0), cls(1))
                for idx, fn in enumerate([lambda a, b: a < b,
                                          lambda a, b: a <= b,
                                          lambda a, b: a > b,
                                          lambda a, b: a >= b]):
                    with self.subTest(idx=idx):
                        with self.assertRaisesRegex(TypeError,
                                                    f"not supported between instances of '{cls.__name__}' and '{cls.__name__}'"):
                            fn(cls(0), cls(0))

        @dataclass(order=True)
        class C:
            x: int
        self.assertLess(C(0), C(1))
        self.assertLessEqual(C(0), C(1))
        self.assertLessEqual(C(1), C(1))
        self.assertGreater(C(1), C(0))
        self.assertGreaterEqual(C(1), C(0))
        self.assertGreaterEqual(C(1), C(1))

    def test_simple_compare(self):
        # Ensure that order=False is the default.
        @dataclass
        class C0:
            x: int
            y: int

        @dataclass(order=False)
        class C1:
            x: int
            y: int

        for cls in [C0, C1]:
            with self.subTest(cls=cls):
                self.assertEqual(cls(0, 0), cls(0, 0))
                self.assertEqual(cls(1, 2), cls(1, 2))
                self.assertNotEqual(cls(1, 0), cls(0, 0))
                self.assertNotEqual(cls(1, 0), cls(1, 1))
                for idx, fn in enumerate([lambda a, b: a < b,
                                          lambda a, b: a <= b,