#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

"""Unit tests for the type-hint objects and decorators."""

# pytype: skip-file

import functools
import sys
import typing
import unittest

from apache_beam import Map
from apache_beam import PTransform
from apache_beam.pvalue import PBegin
from apache_beam.pvalue import PCollection
from apache_beam.pvalue import PDone
from apache_beam.transforms.core import DoFn
from apache_beam.typehints import KV
from apache_beam.typehints import Any
from apache_beam.typehints import Iterable
from apache_beam.typehints import Tuple
from apache_beam.typehints import TypeCheckError
from apache_beam.typehints import Union
from apache_beam.typehints import native_type_compatibility
from apache_beam.typehints import typehints
from apache_beam.typehints import with_input_types
from apache_beam.typehints import with_output_types
from apache_beam.typehints.decorators import GeneratorWrapper
from apache_beam.typehints.decorators import _check_instance_type
from apache_beam.typehints.decorators import _interleave_type_check
from apache_beam.typehints.decorators import _positional_arg_hints
from apache_beam.typehints.decorators import get_signature
from apache_beam.typehints.decorators import get_type_hints
from apache_beam.typehints.decorators import getcallargs_forhints
from apache_beam.typehints.typehints import is_consistent_with
from apache_beam.typehints.typehints import visit_inner_types


def check_or_interleave(hint, value, var):
  if hint is None:
    return value
  elif isinstance(hint, typehints.IteratorHint.IteratorTypeConstraint):
    return _interleave_type_check(hint, var)(value)
  _check_instance_type(hint, value, var)
  return value


def check_type_hints(f):
  @functools.wraps(f)
  def wrapper(*args, **kwargs):
    hints = get_type_hints(f)
    if hints.input_types:  # pylint: disable=too-many-nested-blocks
      input_hints = getcallargs_forhints(
          f, *hints.input_types[0], **hints.input_types[1])
      inputs = get_signature(f).bind(*args, **kwargs).arguments
      for var, hint in input_hints.items():
        value = inputs[var]
        new_value = check_or_interleave(hint, value, var)
        if new_value is not value:
          if var in kwargs:
            kwargs[var] = new_value
          else:
            args = list(args)
            for ix, pvar in enumerate(get_signature(f).parameters):
              if pvar == var:
                args[ix] = new_value
                break
            else:
              raise NotImplementedError('Iterable in nested argument %s' % var)
    res = f(*args, **kwargs)
    return check_or_interleave(hints.simple_output_type('typecheck'), res, None)

  return wrapper


class DummyTestClass1(object):
  pass


class DummyTestClass2(object):
  pass


class SuperClass(object):
  pass


class SubClass(SuperClass):
  pass


class TypeHintTestCase(unittest.TestCase):
  def assertCompatible(self, base, sub):  # pylint: disable=invalid-name
    base, sub = native_type_compatibility.convert_to_beam_types([base, sub])
    self.assertTrue(
        is_consistent_with(sub, base),
        '%s is not consistent with %s' % (sub, base))

  def assertNotCompatible(self, base, sub):  # pylint: disable=invalid-name
    base, sub = native_type_compatibility.convert_to_beam_type([base, sub])
    self.assertFalse(
        is_consistent_with(sub, base), '%s is consistent with %s' % (sub, base))


class TypeVariableTestCase(TypeHintTestCase):
  def test_eq_with_name_check(self):
    use_name_in_eq = True
    self.assertNotEqual(
        typehints.Set[typehints.TypeVariable('T', use_name_in_eq)],
        typehints.Set[typehints.TypeVariable('T2', use_name_in_eq)])

  def test_eq_without_name_check(self):
    use_name_in_eq = False
    self.assertEqual(
        typehints.Set[typehints.TypeVariable('T', use_name_in_eq)],
        typehints.Set[typehints.TypeVariable('T2', use_name_in_eq)])

  def test_eq_with_different_name_checks(self):
    self.assertEqual(
        typehints.Set[typehints.TypeVariable('T', True)],
        typehints.Set[typehints.TypeVariable('T2', False)])
    self.assertEqual(
        typehints.Set[typehints.TypeVariable('T', False)],
        typehints.Set[typehints.TypeVariable('T2', True)])


class AnyTypeConstraintTestCase(TypeHintTestCase):
  def test_any_compatibility(self):
    self.assertCompatible(typehints.Any, typehints.List[int])
    self.assertCompatible(typehints.Any, DummyTestClass1)
    self.assertCompatible(typehints.Union[int, bool], typehints.Any)
    self.assertCompatible(typehints.Optional[int], typehints.Any)
    self.assertCompatible(typehints.Tuple[int], typehints.Any)
    self.assertCompatible(typehints.KV[int, str], typehints.Any)
    self.assertCompatible(typehints.Dict[int, bool], typehints.Any)
    self.assertCompatible(typehints.Set[int], typehints.Any)
    self.assertCompatible(typehints.FrozenSet[int], typehints.Any)
    self.assertCompatible(typehints.Iterable[int], typehints.Any)
    self.assertCompatible(typehints.Iterator[int], typehints.Any)
    self.assertCompatible(typehints.Generator[int], typehints.Any)
    self.assertCompatible(object, typehints.Any)
    self.assertCompatible(typehints.Any, object)

  def test_repr(self):
    self.assertEqual('Any', repr(typehints.Any))

  def test_type_check(self):
    # This test passes if the type_check call does not raise any exception.
    typehints.Any.type_check(1)
    typehints.Any.type_check([1, 2, 3])
    typehints.Any.type_check(DummyTestClass1())


class UnionHintTestCase(TypeHintTestCase):
  def test_getitem_must_be_valid_type_param_cant_be_object_instance(self):
    with self.assertRaises(TypeError) as e:
      typehints.Union[5]
    self.assertEqual(
        'Cannot create Union without a sequence of types.', e.exception.args[0])

  def test_getitem_must_be_valid_type_param(self):
    t = [2, 3]
    with self.assertRaises(TypeError) as e:
      typehints.Union[t]
    self.assertEqual(
        'All parameters to a Union hint must be a non-sequence, '
        'a type, or a TypeConstraint. 2 is an instance of int.',
        e.exception.args[0])

  def test_getitem_duplicates_ignored(self):
    # Types should be de-duplicated.
    hint = typehints.Union[int, int, str]
    self.assertEqual(len(hint.union_types), 2)

  def test_getitem_nested_unions_flattened(self):
    # The two Union's should be merged into 1.
    hint = typehints.Union[typehints.Union[int, str],
                           typehints.Union[float, bool]]
    self.assertTrue(len(hint.union_types) == 4)
    self.assertTrue(all(t in hint.union_types for t in (int, str, float, bool)))

  def test_union_hint_compatibility(self):
    self.assertCompatible(typehints.Union[int, float], int)
    self.assertCompatible(typehints.Union[int, str], typehints.Union[str, int])
    self.assertCompatible(
        typehints.Union[int, float, str], typehints.Union[str, int])

    self.assertCompatible(
        typehints.Union[DummyTestClass1, str],
        typehints.Union[DummyTestClass1, str])

    self.assertCompatible(
        typehints.Union[int, str],
        typehints.Union[str, typehints.Union[int, str]])

    self.assertNotCompatible(
        typehints.Union[float, bool], typehints.Union[int, bool])
    self.assertNotCompatible(
        typehints.Union[bool, str], typehints.Union[float, bool, int])

  def test_nested_compatibility(self):
    self.assertCompatible(Union[int, Tuple[Any, int]], Tuple[int, int])
    self.assertCompatible(
        Union[int, Tuple[Any, Any]], Union[Tuple[int, Any], Tuple[Any, int]])
    self.assertCompatible(Union[int, SuperClass], SubClass)
    self.assertCompatible(Union[int, float, SuperClass], Union[int, SubClass])
    self.assertCompatible(int, Union[()])

    self.assertNotCompatible(Union[int, SubClass], SuperClass)
    self.assertNotCompatible(
        Union[int, float, SubClass], Union[int, SuperClass])
    self.assertNotCompatible(
        Union[int, SuperClass], Union[int, float, SubClass])

    self.assertCompatible(
        Tuple[Any, Any], Union[Tuple[str, int], Tuple[str, float]])

  def test_union_hint_repr(self):
    hint = typehints.Union[DummyTestClass1, str]
    self.assertIn(
        str(hint),
        # Uses frozen set internally, so order not guaranteed.
        [
            "Union[<class 'str'>, <class 'apache_beam.typehints."
            "typehints_test.DummyTestClass1'>]",
            "Union[<class 'apache_beam.typehints.typehints_test"
            ".DummyTestClass1'>, <class 'str'>]"
        ])

  def test_union_hint_enforcement_composite_type_in_union(self):
    o = DummyTestClass1()
    hint = typehints.Union[int, DummyTestClass1]

    self.assertIsNone(hint.type_check(4))
    self.assertIsNone(hint.type_check(o))

  def test_union_hint_enforcement_part_of_union(self):
    hint = typehints.Union[int, str]
    self.assertIsNone(hint.type_check(5))
    self.assertIsNone(hint.type_check('test'))

  def test_union_hint_enforcement_not_part_of_union(self):
    hint = typehints.Union[int, float]
    with self.assertRaises(TypeError) as e:
      hint.type_check('test')

    self.assertEqual(
        "Union[<class \'float\'>, <class \'int\'>] type-constraint violated. "
        "Expected an instance of one of: (\"<class \'float\'>\", \"<class "
        "\'int\'>\"), received str instead.",
        e.exception.args[0])

  def test_dict_union(self):
    hint = Union[typehints.Dict[Any, int], typehints.Dict[Union[()], Union[()]]]
    self.assertEqual(typehints.Dict[Any, int], hint)

  def test_empty_union(self):
    self.assertEqual(
        typehints.Union[()],
        typehints.Union[typehints.Union[()], typehints.Union[()]])
    self.assertEqual(int, typehints.Union[typehints.Union[()], int])

  def test_match_type_variables(self):
    A = typehints.TypeVariable('A')  # pylint: disable=invalid-name
    B = typehints.TypeVariable('B')  # pylint: disable=invalid-name
    self.assertEqual(
        typehints.Union[A, int].match_type_variables(str), {A: str})
    self.assertEqual(typehints.Union[A, int].match_type_variables(int), {})
    self.assertEqual(typehints.Union[A, B, int].match_type_variables(str), {})
    # We could do better here, but most importantly we don't want to
    # incorrectly infer A is a float.
    self.assertEqual(
        typehints.Tuple[A, typehints.Union[A, B, int]].match_type_variables(
            typehints.Tuple[str, float]), {A: str})

    self.assertEqual(
        typehints.Union[Tuple[str, A], Tuple[float, B]].match_type_variables(
            typehints.Tuple[Any, int]), {})
    self.assertEqual(
        typehints.Union[Tuple[str, A], Tuple[float, A]].match_type_variables(
            typehints.Tuple[Any, int]), {A: int})
    self.assertEqual(
        typehints.Union[Tuple[str, A], Tuple[float, B]].match_type_variables(
            typehints.Tuple[str, int]), {A: int})

  def test_bind_type_variables(self):
    A = typehints.TypeVariable('A')  # pylint: disable=invalid-name
    B = typehints.TypeVariable('B')  # pylint: disable=invalid-name
    hint = typehints.Union[A, B, int]
    self.assertEqual(
        hint.bind_type_variables({
            A: str, B: float
        }),
        typehints.Union[str, float, int])
    self.assertEqual(
        hint.bind_type_variables({
            A: str, B: int
        }), typehints.Union[str, int])
    self.assertEqual(hint.bind_type_variables({A: int, B: int}), int)

  def test_visit_inner_types(self):
    A = typehints.TypeVariable('A')  # pylint: disable=invalid-name
    B = typehints.TypeVariable('B')  # pylint: disable=invalid-name
    hint = typehints.Tuple[Tuple[A, A], B, int]

    user_data = object()
    nodes = []

    def visitor(hint, arg):
      self.assertIs(arg, user_data)
      nodes.append(hint)

    visit_inner_types(hint, visitor, user_data)
    self.assertEqual(nodes, [hint, Tuple[A, A], A, A, B, int])


class OptionalHintTestCase(TypeHintTestCase):
  def test_getitem_sequence_not_allowed(self):
    with self.assertRaises(TypeError) as e:
      typehints.Optional[int, str]
    self.assertTrue(
        e.exception.args[0].startswith(
            'An Option type-hint only accepts a single type parameter.'))

  def test_getitem_proxy_to_union(self):
    hint = typehints.Optional[int]
    self.assertTrue(isinstance(hint, typehints.UnionHint.UnionConstraint))

  def test_is_optional(self):
    hint1 = typehints.Optional[int]
    self.assertTrue(typehints.is_nullable(hint1))
    hint2 = typehints.UnionConstraint({int, bytes})
    self.assertFalse(typehints.is_nullable(hint2))
    hint3 = typehints.UnionConstraint({int, bytes, type(None)})
    self.assertFalse(typehints.is_nullable(hint3))


class TupleHintTestCase(TypeHintTestCase):
  def test_getitem_invalid_ellipsis_type_param(self):
    error_msg = (
        'Ellipsis can only be used to type-hint an arbitrary length '
        'tuple of containing a single type: Tuple[A, ...].')

    with self.assertRaises(TypeError) as e:
      typehints.Tuple[int, int, ...]
    self.assertEqual(error_msg, e.exception.args[0])

    with self.assertRaises(TypeError) as e:
      typehints.Tuple[...]
    self.assertEqual(error_msg, e.exception.args[0])

  def test_getitem_params_must_be_type_or_constraint(self):
    expected_error_prefix = 'All parameters to a Tuple hint must be'
    with self.assertRaises(TypeError) as e:
      typehints.Tuple[5, [1, 3]]
    self.assertTrue(e.exception.args[0].startswith(expected_error_prefix))

    with self.assertRaises(TypeError) as e:
      typehints.Tuple[list, dict]
    self.assertTrue(e.exception.args[0].startswith(expected_error_prefix))

  def test_compatibility_arbitrary_length(self):
    self.assertNotCompatible(
        typehints.Tuple[int, int], typehints.Tuple[int, ...])
    self.assertCompatible(typehints.Tuple[int, ...], typehints.Tuple[int, int])
    self.assertCompatible(
        typehints.Tuple[Any, ...], typehints.Tuple[int, float])
    self.assertCompatible(
        typehints.Tuple[SuperClass, ...], typehints.Tuple[SubClass, SuperClass])

    self.assertCompatible(typehints.Iterable[int], typehints.Tuple[int, ...])
    self.assertCompatible(
        typehints.Iterable[SuperClass], typehints.Tuple[SubClass, ...])

  def test_compatibility(self):
    self.assertCompatible(typehints.Tuple[int, str], typehints.Tuple[int, str])
    self.assertCompatible(typehints.Tuple[int, Any], typehints.Tuple[int, str])
    self.assertCompatible(typehints.Tuple[int, str], typehints.Tuple[int, Any])
    self.assertCompatible(
        typehints.Tuple[typehints.Union[int, str], bool],
        typehints.Tuple[typehints.Union[int, str], bool])
    self.assertCompatible(
        typehints.Tuple[typehints.Union[str, int], int],
        typehints.Tuple[typehints.Union[int, str], int])
    self.assertCompatible(
        typehints.Tuple[SuperClass, int], typehints.Tuple[SubClass, int])

    self.assertNotCompatible(
        typehints.Tuple[int, int], typehints.Tuple[int, int, int])

  def test_raw_tuple(self):
    self.assertCompatible(tuple, typehints.Tuple[int])
    self.assertCompatible(tuple, typehints.Tuple[int, float])
    self.assertCompatible(tuple, typehints.Tuple[int, ...])

  def test_repr(self):
    hint = typehints.Tuple[int, str, float]
    self.assertEqual(
        'Tuple[<class \'int\'>, <class \'str\'>, <class \'float\'>]', str(hint))

    hint = typehints.Tuple[DummyTestClass1, DummyTestClass2]
    self.assertEqual(
        'Tuple[<class \'apache_beam.typehints.typehints_test.' \
        'DummyTestClass1\'>, <class \'apache_beam.typehints.typehints_test.' \
        'DummyTestClass2\'>]',
        str(hint))

    hint = typehints.Tuple[float, ...]
    self.assertEqual('Tuple[<class \'float\'>, ...]', str(hint))

  def test_type_check_must_be_tuple(self):
    hint = typehints.Tuple[int, str]
    expected_error_prefix = 'Tuple type constraint violated. Valid object'
    invalid_instances = ([1, 2, 3], {4: 'f'}, 9, 'test', None)
    for t in invalid_instances:
      with self.assertRaises(TypeError) as e:
        hint.type_check(t)
      self.assertTrue(e.exception.args[0].startswith(expected_error_prefix))

  def test_type_check_must_have_same_arity(self):
    # A 2-tuple of ints.
    hint = typehints.Tuple[int, int]
    t = (1, 2, 3)

    with self.assertRaises(TypeError) as e:
      hint.type_check(t)
    self.assertEqual(
        'Passed object instance is of the proper type, but '
        'differs in length from the hinted type. Expected a '
        'tuple of length 2, received a tuple of length 3.',
        e.exception.args[0])

  def test_type_check_invalid_simple_types(self):
    hint = typehints.Tuple[str, bool]
    with self.assertRaises(TypeError) as e:
      hint.type_check((4, False))
    self.assertEqual(
        'Tuple[<class \'str\'>, <class \'bool\'>] hint type-constraint '
        'violated. The type of element #0 in the passed tuple is incorrect.'
        ' Expected an instance of type <class \'str\'>, instead received '
        'an instance of type int.',
        e.exception.args[0])

  def test_type_check_invalid_composite_type(self):
    hint = typehints.Tuple[DummyTestClass1, DummyTestClass2]
    t = (DummyTestClass2(), DummyTestClass1())
    with self.assertRaises(TypeError) as e:
      hint.type_check(t)

    self.assertEqual(
        'Tuple[<class \'apache_beam.typehints.typehints_test.DummyTestClass1'
        '\'>, <class \'apache_beam.typehints.typehints_test.DummyTestClass2\'>]'
        ' hint type-constraint violated. The type of element #0 in the '
        'passed tuple is incorrect. Expected an instance of type '
        '<class \'apache_beam.typehints.typehints_test.DummyTestClass1\'>, '
        'instead received an instance of type '
        'DummyTestClass2.',
        e.exception.args[0])

  def test_type_check_valid_simple_types(self):
    hint = typehints.Tuple[float, bool]
    self.assertIsNone(hint.type_check((4.3, True)))

    hint = typehints.Tuple[int]
    self.assertIsNone(hint.type_check((1, )))

  def test_type_check_valid_composite_types(self):
    hint = typehints.Tuple[typehints.Tuple[int, str],
                           typehints.Tuple[int, bool]]
    self.assertIsNone(hint.type_check(((4, 'test'), (4, True))))

  def test_type_check_valid_simple_type_arbitrary_length(self):
    hint = typehints.Tuple[int, ...]
    t = (1, 2, 3, 4)
    self.assertIsNone(hint.type_check(t))

  def test_type_check_valid_composite_type_arbitrary_length(self):
    hint = typehints.Tuple[typehints.List[str], ...]
    t = (['h', 'e'], ['l', 'l'], ['o'])
    self.assertIsNone(hint.type_check(t))

  def test_type_check_invalid_simple_type_arbitrary_length(self):
    hint = typehints.Tuple[str, ...]

    t = ('t', 'e', 5, 't')
    with self.assertRaises(TypeError) as e:
      hint.type_check(t)

    self.assertEqual(
        'Tuple[<class \'str\'>, ...] hint type-constraint violated. The type '
        'of element #2 in the passed <class \'tuple\'> is incorrect. Expected '
        'an instance of type <class \'str\'>, instead received an instance of '
        'type int.',
        e.exception.args[0])

  def test_type_check_invalid_composite_type_arbitrary_length(self):
    hint = typehints.Tuple[typehints.List[int], ...]

    t = ([1, 2], 'e', 's', 't')
    with self.assertRaises(TypeError) as e:
      hint.type_check(t)

    self.assertEqual(
        "Tuple[List[<class \'int\'>], ...] hint type-constraint violated. The "
        "type of element #1 in the passed tuple is incorrect: "
        "List type-constraint violated. Valid object instance "
        "must be of type 'list'. Instead, an instance of 'str' "
        "was received.",
        e.exception.args[0])


class ListHintTestCase(TypeHintTestCase):
  def test_getitem_invalid_composite_type_param(self):
    with self.assertRaises(TypeError):
      typehints.List[4]

  def test_list_constraint_compatibility(self):
    hint1 = typehints.List[typehints.Tuple[int, str]]
    hint2 = typehints.List[typehints.Tuple[float, bool]]

    self.assertCompatible(hint1, hint1)
    self.assertNotCompatible(hint1, hint2)

    self.assertCompatible(typehints.List[SuperClass], typehints.List[SubClass])

  def test_list_repr(self):
    hint = (typehints.List[typehints.Tuple[DummyTestClass1, DummyTestClass2]])
    self.assertEqual(
        'List[Tuple[<class \'apache_beam.typehints.typehints_test.'
        'DummyTestClass1\'>, <class \'apache_beam.typehints.typehints_test.'
        'DummyTestClass2\'>]]',
        repr(hint))

  def test_enforce_list_type_constraint_valid_simple_type(self):
    hint = typehints.List[int]
    self.assertIsNone(hint.type_check([1, 2, 3]))

  def test_enforce_list_type_constraint_valid_composite_type(self):
    hint = typehints.List[DummyTestClass1]
    l = [DummyTestClass1(), DummyTestClass1()]
    self.assertIsNone(hint.type_check(l))

  def test_enforce_list_type_constraint_invalid_simple_type(self):
    hint = typehints.List[int]
    l = ['f', 'd', 'm']
    with self.assertRaises(TypeError) as e:
      hint.type_check(l)
    self.assertEqual(
        'List[<class \'int\'>] hint type-constraint violated. The type of '
        'element #0 in the passed <class \'list\'> is incorrect. Expected an '
        'instance of type <class \'int\'>, instead received an instance of '
        'type str.',
        e.exception.args[0])

  def test_enforce_list_type_constraint_invalid_composite_type(self):
    hint = typehints.List[typehints.Tuple[int, int]]
    l = [('f', 1), ('m', 5)]
    with self.assertRaises(TypeError) as e:
      hint.type_check(l)

    self.assertEqual(
        'List[Tuple[<class \'int\'>, <class \'int\'>]] hint type-constraint '
        'violated. The type of element #0 in the passed list is '
        'incorrect: Tuple[<class \'int\'>, <class \'int\'>] hint '
        'type-constraint violated. The type of element #0 in the passed tuple'
        ' is incorrect. Expected an instance of type <class \'int\'>, '
        'instead received an instance of type str.',
        e.exception.args[0])


class KVHintTestCase(TypeHintTestCase):
  def test_getitem_param_must_be_tuple(self):
    with self.assertRaises(TypeError) as e:
      typehints.KV[4]

    self.assertEqual(
        'Parameter to KV type-hint must be a tuple of types: '
        'KV[.., ..].',
        e.exception.args[0])

  def test_getitem_param_must_have_length_2(self):
    with self.assertRaises(TypeError) as e:
      typehints.KV[int, str, bool]

    self.assertEqual(
        "Length of parameters to a KV type-hint must be "
        "exactly 2. Passed parameters: ({}, {}, {}), have a "
        "length of 3.".format(int, str, bool),
        e.exception.args[0])

  def test_getitem_proxy_to_tuple(self):
    hint = typehints.KV[int, str]
    self.assertTrue(isinstance(hint, typehints.Tuple.TupleConstraint))

  def test_enforce_kv_type_constraint(self):
    hint = typehints.KV[str, typehints.Tuple[int, int, int]]
    t = ('test', (1, 2, 3))
    self.assertIsNone(hint.type_check(t))


class DictHintTestCase(TypeHintTestCase):
  def test_getitem_param_must_be_tuple(self):
    with self.assertRaises(TypeError) as e:
      typehints.Dict[4]

    self.assertEqual(
        'Parameter to Dict type-hint must be a tuple of '
        'types: Dict[.., ..].',
        e.exception.args[0])

  def test_getitem_param_must_have_length_2(self):
    with self.assertRaises(TypeError) as e:
      typehints.Dict[float, int, bool]

    self.assertEqual(
        "Length of parameters to a Dict type-hint must be "
        "exactly 2. Passed parameters: ({}, {}, {}), have a "
        "length of 3.".format(float, int, bool),
        e.exception.args[0])

  def test_key_type_must_be_valid_composite_param(self):
    with self.assertRaises(TypeError):
      typehints.Dict[list, int]

  def test_value_type_must_be_valid_composite_param(self):
    with self.assertRaises(TypeError):
      typehints.Dict[str, 5]

  def test_compatibility(self):
    hint1 = typehints.Dict[int, str]
    hint2 = typehints.Dict[bool, int]
    hint3 = typehints.Dict[int, typehints.List[typehints.Tuple[str, str, str]]]
    hint4 = typehints.Dict[int, int]

    self.assertCompatible(hint1, hint1)
    self.assertCompatible(hint3, hint3)
    self.assertNotCompatible(hint3, 4)
    self.assertNotCompatible(hint2, hint1)  # Key incompatibility.
    self.assertNotCompatible(hint1, hint4)  # Value incompatibility.

  def test_repr(self):
    hint3 = typehints.Dict[int, typehints.List[typehints.Tuple[str, str, str]]]
    self.assertEqual(
        'Dict[<class \'int\'>, List[Tuple[<class \'str\'>, ' \
        '<class \'str\'>, <class \'str\'>]]]',
        repr(hint3))

  def test_type_checks_not_dict(self):
    hint = typehints.Dict[int, str]
    l = [1, 2]
    with self.assertRaises(TypeError) as e:
      hint.type_check(l)
    self.assertEqual(
        'Dict type-constraint violated. All passed instances '
        'must be of type dict. [1, 2] is of type list.',
        e.exception.args[0])

  def test_type_check_invalid_key_type(self):
    hint = typehints.Dict[typehints.Tuple[int, int, int], typehints.List[str]]
    d = {(1, 2): ['m', '1', '2', '3']}
    with self.assertRaises((TypeError, TypeError)) as e:
      hint.type_check(d)
    self.assertEqual(
        'Dict[Tuple[<class \'int\'>, <class \'int\'>, <class \'int\'>], '
        'List[<class \'str\'>]] hint key-type '
        'constraint violated. All keys should be of type '
        'Tuple[<class \'int\'>, <class \'int\'>, <class \'int\'>]. Instead: '
        'Passed object instance is of the proper type, but differs in '
        'length from the hinted type. Expected a tuple of '
        'length 3, received a tuple of length 2.',
        e.exception.args[0])

  def test_type_check_invalid_value_type(self):
    hint = typehints.Dict[str, typehints.Dict[int, str]]
    d = {'f': [1, 2, 3]}
    with self.assertRaises(TypeError) as e:
      hint.type_check(d)
    self.assertEqual(
        'Dict[<class \'str\'>, Dict[<class \'int\'>, <class \'str\'>]] hint '
        'value-type constraint violated. All values should be of type '
        'Dict[<class \'int\'>, <class \'str\'>]. Instead: Dict type-constraint '
        'violated. All passed instances must be of type dict.'
        ' [1, 2, 3] is of type list.',
        e.exception.args[0])

  def test_type_check_valid_simple_type(self):
    hint = typehints.Dict[int, str]
    d = {4: 'f', 9: 'k'}
    self.assertIsNone(hint.type_check(d))

  def test_type_check_valid_composite_type(self):
    hint = typehints.Dict[typehints.Tuple[str, str], typehints.List[int]]
    d = {('f', 'k'): [1, 2, 3], ('m', 'r'): [4, 6, 9]}
    self.assertIsNone(hint.type_check(d))

  def test_match_type_variables(self):
    S = typehints.TypeVariable('S')  # pylint: disable=invalid-name
    T = typehints.TypeVariable('T')  # pylint: disable=invalid-name
    hint = typehints.Dict[S, T]
    self.assertEqual({
        S: int, T: str
    },
                     hint.match_type_variables(typehints.Dict[int, str]))


class BaseSetHintTest:
  class CommonTests(TypeHintTestCase):
    def test_getitem_invalid_composite_type_param(self):
      with self.assertRaises(TypeError) as e:
        self.beam_type[list]
      self.assertEqual(
          "Parameter to a {} hint must be a non-sequence, a "
          "type, or a TypeConstraint. {} is an instance of "
          "type.".format(self.string_type, list),
          e.exception.args[0])

    def test_compatibility(self):
      hint1 = self.beam_type[typehints.List[str]]
      hint2 = self.beam_type[typehints.Tuple[int, int]]

      self.assertCompatible(hint1, hint1)
      self.assertNotCompatible(hint2, hint1)

    def test_repr(self):
      hint = self.beam_type[typehints.List[bool]]
      self.assertEqual(
          '{}[List[<class \'bool\'>]]'.format(self.string_type), repr(hint))

    def test_type_check_must_be_set(self):
      hint = self.beam_type[str]
      with self.assertRaises(TypeError) as e:
        hint.type_check(4)
        self.assertEqual(
            "{} type-constraint violated. Valid object instance "
            "must be of type '{}'. Instead, an instance of 'int'"
            " was received.".format(self.py_type, self.py_type.__name__),
            e.exception.args[0])

    def test_type_check_invalid_elem_type(self):
      hint = self.beam_type[float]
      with self.assertRaises(TypeError):
        hint.type_check('f')

    def test_type_check_valid_elem_simple_type(self):
      hint = self.beam_type[str]
      s = self.py_type(['f', 'm', 'k'])
      self.assertIsNone(hint.type_check(s))

    def test_type_check_valid_elem_composite_type(self):
      hint = self.beam_type[typehints.Union[int, str]]
      s = self.py_type([9, 'm', 'k'])
      self.assertIsNone(hint.type_check(s))


class SetHintTestCase(BaseSetHintTest.CommonTests):
  py_type = set
  beam_type = typehints.Set
  string_type = 'Set'


class FrozenSetHintTestCase(BaseSetHintTest.CommonTests):
  py_type = frozenset
  beam_type = typehints.FrozenSet
  string_type = 'FrozenSet'


class IterableHintTestCase(TypeHintTestCase):
  def test_getitem_invalid_composite_type_param(self):
    with self.assertRaises(TypeError) as e:
      typehints.Iterable[5]
    self.assertEqual(
        'Parameter to an Iterable hint must be a '
        'non-sequence, a type, or a TypeConstraint. 5 is '
        'an instance of int.',
        e.exception.args[0])

  def test_compatibility(self):
    self.assertCompatible(typehints.Iterable[int], typehints.List[int])
    self.assertCompatible(typehints.Iterable[int], typehints.Set[int])
    self.assertCompatible(
        typehints.Iterable[typehints.Any],
        typehints.List[typehints.Tuple[int, bool]])

    self.assertCompatible(typehints.Iterable[int], typehints.Iterable[int])
    self.assertCompatible(
        typehints.Iterable[typehints.Union[int, str]],
        typehints.Iterable[typehints.Union[int, str]])
    self.assertNotCompatible(typehints.Iterable[str], typehints.Iterable[bool])

    self.assertCompatible(typehints.Iterable[int], typehints.List[int])
    self.assertCompatible(typehints.Iterable[int], typehints.Set[int])
    self.assertCompatible(
        typehints.Iterable[typehints.Any],
        typehints.List[typehints.Tuple[int, bool]])

  def test_tuple_compatibility(self):
    self.assertCompatible(typehints.Iterable[int], typehints.Tuple[int, ...])
    self.assertCompatible(
        typehints.Iterable[SuperClass], typehints.Tuple[SubClass, ...])
    self.assertCompatible(typehints.Iterable[int], typehints.Tuple[int, int])
    self.assertCompatible(typehints.Iterable[Any], typehints.Tuple[int, float])
    self.assertCompatible(
        typehints.Iterable[typehints.Union[int, float]],
        typehints.Tuple[int, ...])
    self.assertCompatible(
        typehints.Iterable[typehints.Union[int, float]],
        typehints.Tuple[int, float])
    self.assertCompatible(
        typehints.Iterable[typehints.Union[int, float]],
        typehints.Tuple[int, float, int])

  def test_repr(self):
    hint = typehints.Iterable[typehints.Set[str]]
    self.assertEqual('Iterable[Set[<class \'str\'>]]', repr(hint))

  def test_type_check_must_be_iterable(self):
    with self.assertRaises(TypeError) as e:
      hint = typehints.Iterable[int]
      hint.type_check(5)

    self.assertEqual(
        "Iterable type-constraint violated. Valid object "
        "instance must be of type 'iterable'. Instead, an "
        "instance of 'int' was received.",
        e.exception.args[0])

  def test_type_check_violation_invalid_simple_type(self):
    hint = typehints.Iterable[float]
    l = set([1, 2, 3, 4])
    with self.assertRaises(TypeError):
      hint.type_check(l)

  def test_type_check_violation_valid_simple_type(self):
    hint = typehints.Iterable[str]
    l = ('t', 'e', 's', 't')
    self.assertIsNone(hint.type_check(l))

  def test_type_check_violation_invalid_composite_type(self):
    hint = typehints.Iterable[typehints.List[int]]
    l = ([['t', 'e'], ['s', 't']])
    with self.assertRaises(TypeError):
      hint.type_check(l)

  def test_type_check_violation_valid_composite_type(self):
    hint = typehints.Iterable[typehints.List[int]]
    l = ([[1, 2], [3, 4, 5]])
    self.assertIsNone(hint.type_check(l))


class TestGeneratorWrapper(TypeHintTestCase):
  def test_functions_as_regular_generator(self):
    def count(n):
      for i in range(n):
        yield i

    l = []
    interleave_func = lambda x: l.append(x)
    wrapped_gen = GeneratorWrapper(count(4), interleave_func)

    # Should function as a normal generator.
    self.assertEqual(0, next(wrapped_gen))
    self.assertEqual((1, 2, 3), tuple(wrapped_gen))

    # Interleave function should have been called each time.
    self.assertEqual([0, 1, 2, 3], l)


class GeneratorHintTestCase(TypeHintTestCase):
  def test_repr(self):
    hint = typehints.Iterator[typehints.Set[str]]
    self.assertEqual('Iterator[Set[<class \'str\'>]]', repr(hint))

  def test_compatibility(self):
    self.assertCompatible(typehints.Iterator[int], typehints.Iterator[int])
    self.assertNotCompatible(typehints.Iterator[str], typehints.Iterator[float])

  def test_conversion(self):
    self.assertCompatible(typehints.Iterator[int], typehints.Generator[int])
    self.assertCompatible(
        typehints.Iterator[int], typehints.Generator[int, None, None])

  def test_generator_return_hint_invalid_yield_type(self):
    @check_type_hints
    @with_output_types(typehints.Iterator[int])
    def all_upper(s):
      for e in s:
        yield e.upper()

    with self.assertRaises(TypeCheckError) as e:
      next(all_upper('hello'))

    self.assertEqual(
        'Type-hint for return type violated: Iterator[<class \'int\'>] '
        'hint type-constraint violated. Expected a iterator '
        'of type <class \'int\'>. Instead received a iterator of type '
        'str.',
        e.exception.args[0])

  def test_generator_argument_hint_invalid_yield_type(self):
    def wrong_yield_gen():
      for e in ['a', 'b']:
        yield e

    @check_type_hints
    @with_input_types(a=typehints.Iterator[int])
    def increment(a):
      return [e + 1 for e in a]

    with self.assertRaises(TypeCheckError) as e:
      increment(wrong_yield_gen())

    self.assertEqual(
        "Type-hint for argument: 'a' violated: Iterator[<class \'int\'>] "
        "hint type-constraint violated. Expected a iterator "
        "of type <class \'int\'>. Instead received a iterator of type "
        "str.",
        e.exception.args[0])


class TakesDecoratorTestCase(TypeHintTestCase):
  def test_must_be_primitive_type_or_constraint(self):
    with self.assertRaises(TypeError) as e:
      t = [1, 2]

      @with_input_types(a=t)
      def unused_foo(a):
        pass

    self.assertEqual(
        'All type hint arguments must be a non-sequence, a '
        'type, or a TypeConstraint. [1, 2] is an instance of '
        'list.',
        e.exception.args[0])

    with self.assertRaises(TypeError) as e:
      t = 5

      @check_type_hints
      @with_input_types(a=t)
      def unused_foo(a):
        pass

    self.assertEqual(
        'All type hint arguments must be a non-sequence, a type, '
        'or a TypeConstraint. 5 is an instance of int.',
        e.exception.args[0])

  def test_basic_type_assertion(self):
    @check_type_hints
    @with_input_types(a=int)
    def foo(a):
      return a + 1

    with self.assertRaises(TypeCheckError) as e:
      m = 'a'
      foo(m)
    self.assertEqual(
        "Type-hint for argument: 'a' violated. Expected an "
        "instance of {}, instead found an instance of "
        "{}.".format(int, type(m)),
        e.exception.args[0])

  def test_composite_type_assertion(self):
    @check_type_hints
    @with_input_types(a=typehints.List[int])
    def foo(a):
      a.append(1)
      return a

    with self.assertRaises(TypeCheckError) as e:
      m = ['f', 'f']
      foo(m)
      self.assertEqual(
          "Type-hint for argument: 'a' violated: List[<class \'int\'>] hint "
          "type-constraint violated. The type of element #0 in "
          "the passed list is incorrect. Expected an instance of "
          "type int, instead received an instance of type str.",
          e.exception.args[0])

  def test_valid_simple_type_arguments(self):
    @with_input_types(a=str)
    def upper(a):
      return a.upper()

    # Type constraints should pass, and function will be evaluated as normal.
    self.assertEqual('M', upper('m'))

  def test_any_argument_type_hint(self):
    @check_type_hints
    @with_input_types(a=typehints.Any)
    def foo(a):
      return 4

    self.assertEqual(4, foo('m'))

  def test_valid_mix_positional_and_keyword_arguments(self):
    @check_type_hints
    @with_input_types(typehints.List[int], elem=typehints.List[int])
    def combine(container, elem):
      return container + elem

    self.assertEqual([1, 2, 3], combine([1, 2], [3]))

  def test_invalid_only_positional_arguments(self):
    @check_type_hints
    @with_input_types(int, int)
    def sub(a, b):
      return a - b

    with self.assertRaises(TypeCheckError) as e:
      m = 'two'
      sub(1, m)

    self.assertEqual(
        "Type-hint for argument: 'b' violated. Expected an "
        "instance of {}, instead found an instance of "
        "{}.".format(int, type(m)),
        e.exception.args[0])

  def test_valid_only_positional_arguments(self):
    @with_input_types(int, int)
    def add(a, b):
      return a + b

    self.assertEqual(3, add(1, 2))


class InputDecoratorTestCase(TypeHintTestCase):
  def test_valid_hint(self):
    @with_input_types(int, int)
    def unused_add(a, b):
      return a + b

    @with_input_types(int, b=int)
    def unused_add2(a, b):
      return a + b

    @with_input_types(a=int, b=int)
    def unused_add3(a, b):
      return a + b

  def test_invalid_kw_hint(self):
    with self.assertRaisesRegex(TypeError, r'\[1, 2\]'):

      @with_input_types(a=[1, 2])
      def unused_foo(a):
        pass

  def test_invalid_pos_hint(self):
    with self.assertRaisesRegex(TypeError, r'\[1, 2\]'):

      @with_input_types([1, 2])
      def unused_foo(a):
        pass


class OutputDecoratorTestCase(TypeHintTestCase):
  def test_valid_hint(self):
    @with_output_types(int)
    def unused_foo():
      return 5

    @with_output_types(None)
    def unused_foo():
      return 5

    @with_output_types(Tuple[int, str])
    def unused_foo():
      return 5, 'bar'

  def test_no_kwargs_accepted(self):
    with self.assertRaisesRegex(ValueError, r'must be positional'):

      @with_output_types(m=int)
      def unused_foo():
        return 5

  def test_must_be_primitive_type_or_type_constraint(self):
    with self.assertRaises(TypeError):

      @with_output_types(5)
      def unused_foo():
        pass

    with self.assertRaises(TypeError):

      @with_output_types([1, 2])
      def unused_foo():
        pass

  def test_must_be_single_return_type(self):
    with self.assertRaises(ValueError):

      @with_output_types(int, str)
      def unused_foo():
        return 4, 'f'

  def test_type_check_violation(self):
    @check_type_hints
    @with_output_types(int)
    def foo(a):
      return 'test'

    with self.assertRaises(TypeCheckError) as e:
      m = 4
      foo(m)

    self.assertEqual(
        "Type-hint for return type violated. Expected an "
        "instance of {}, instead found an instance of "
        "{}.".format(int, type('test')),
        e.exception.args[0])

  def test_type_check_simple_type(self):
    @check_type_hints
    @with_output_types(str)
    def upper(a):
      return a.upper()

    self.assertEqual('TEST', upper('test'))

  def test_type_check_composite_type(self):
    @check_type_hints
    @with_output_types(typehints.List[typehints.Tuple[int, int]])
    def bar():
      return [(i, i + 1) for i in range(5)]

    self.assertEqual([(0, 1), (1, 2), (2, 3), (3, 4), (4, 5)], bar())

  def test_any_return_type_hint(self):
    @check_type_hints
    @with_output_types(typehints.Any)
    def bar():
      return 'foo'

    self.assertEqual('foo', bar())


class CombinedReturnsAndTakesTestCase(TypeHintTestCase):
  def test_enable_and_disable_type_checking_takes(self):
    @with_input_types(a=int)
    def int_to_str(a):
      return str(a)

    # The function call below violates the argument type-hint above, but won't
    # result in an exception since run-time type-checking was disabled above.
    self.assertEqual('a', int_to_str('a'))

    # Must re-define since the conditional is in the (maybe)wrapper.
    @check_type_hints
    @with_input_types(a=int)
    def int_to_str(a):  # pylint: disable=function-redefined
      return str(a)

    # With run-time type checking enabled once again the same call-atttempt
    # should result in a TypeCheckError.
    with self.assertRaises(TypeCheckError):
      int_to_str('a')

  def test_enable_and_disable_type_checking_returns(self):
    @with_output_types(str)
    def int_to_str(a):
      return a

    # The return value of the function above violates the return-type
    # type-hint above, but won't result in an exception since run-time
    # type-checking was disabled above.
    self.assertEqual(9, int_to_str(9))

    # Must re-define since the conditional is in the (maybe)wrapper.
    @check_type_hints
    @with_output_types(str)
    def int_to_str(a):  # pylint: disable=function-redefined
      return a

    # With type-checking enabled once again we should get a TypeCheckError here.
    with self.assertRaises(TypeCheckError):
      int_to_str(9)

  def test_valid_mix_pos_and_keyword_with_both_orders(self):
    @with_input_types(str, start=int)
    @with_output_types(str)
    def to_upper_with_slice(string, start):
      return string.upper()[start:]

    self.assertEqual('ELLO', to_upper_with_slice('hello', 1))

  def test_simple_takes_and_returns_hints(self):
    @check_type_hints
    @with_output_types(str)
    @with_input_types(a=str)
    def to_lower(a):
      return a.lower()

    # Return type and argument type satisfied, should work as normal.
    self.assertEqual('m', to_lower('M'))

    # Invalid argument type should raise a TypeCheckError
    with self.assertRaises(TypeCheckError):
      to_lower(5)

    @check_type_hints
    @with_output_types(str)
    @with_input_types(a=str)
    def to_lower(a):  # pylint: disable=function-redefined
      return 9

    # Modified function now has an invalid return type.
    with self.assertRaises(TypeCheckError):
      to_lower('a')

  def test_composite_takes_and_returns_hints(self):
    @check_type_hints
    @with_input_types(it=typehints.List[int])
    @with_output_types(typehints.List[typehints.Tuple[int, int]])
    def expand_ints(it):
      return [(i, i + 1) for i in it]

    # Return type and argument type satisfied, should work as normal.
    self.assertEqual([(0, 1), (1, 2), (2, 3)], expand_ints(list(range(3))))

    # Invalid argument, list of str instead of int.
    with self.assertRaises(TypeCheckError):
      expand_ints('t e s t'.split())

    @check_type_hints
    @with_output_types(typehints.List[typehints.Tuple[int, int]])
    @with_input_types(it=typehints.List[int])
    def expand_ints(it):  # pylint: disable=function-redefined
      return [str(i) for i in it]

    # Modified function now has invalid return type.
    with self.assertRaises(TypeCheckError):
      expand_ints(list(range(2)))


class DecoratorHelpers(TypeHintTestCase):
  def test_hint_helper(self):
    self.assertTrue(is_consistent_with(Any, int))
    self.assertTrue(is_consistent_with(int, Any))
    self.assertTrue(is_consistent_with(str, object))
    self.assertFalse(is_consistent_with(object, str))
    self.assertTrue(is_consistent_with(str, Union[str, int]))
    self.assertFalse(is_consistent_with(Union[str, int], str))

  def test_positional_arg_hints(self):
    self.assertEqual(typehints.Any, _positional_arg_hints('x', {}))
    self.assertEqual(int, _positional_arg_hints('x', {'x': int}))
    self.assertEqual(
        typehints.Tuple[int, typehints.Any],
        _positional_arg_hints(['x', 'y'], {'x': int}))

  def test_getcallargs_forhints(self):
    def func(a, b_c, *d):
      return a, b_c, d

    self.assertEqual({
        'a': Any, 'b_c': Any, 'd': Tuple[Any, ...]
    },
                     getcallargs_forhints(func, *[Any, Any]))
    self.assertEqual({
        'a': Any, 'b_c': Any, 'd': Tuple[Union[int, str], ...]
    },
                     getcallargs_forhints(func, *[Any, Any, str, int]))
    self.assertEqual({
        'a': int, 'b_c': Tuple[str, Any], 'd': Tuple[Any, ...]
    },
                     getcallargs_forhints(func, *[int, Tuple[str, Any]]))
    self.assertEqual({
        'a': Any, 'b_c': Any, 'd': Tuple[str, ...]
    },
                     getcallargs_forhints(func, *[Any, Any, Tuple[str, ...]]))
    self.assertEqual({
        'a': Any, 'b_c': Any, 'd': Tuple[Union[Tuple[str, ...], int], ...]
    },
                     getcallargs_forhints(
                         func, *[Any, Any, Tuple[str, ...], int]))

  def test_getcallargs_forhints_builtins(self):
    if sys.version_info < (3, 7):
      # Signatures for builtins are not supported in 3.5 and 3.6.
      self.assertEqual({
          '_': str,
          '__unknown__varargs': Tuple[Any, ...],
          '__unknown__keywords': typehints.Dict[Any, Any]
      },
                       getcallargs_forhints(str.upper, str))
      self.assertEqual({
          '_': str,
          '__unknown__varargs': Tuple[str, ...],
          '__unknown__keywords': typehints.Dict[Any, Any]
      },
                       getcallargs_forhints(str.strip, str, str))
      self.assertEqual({
          '_': str,
          '__unknown__varargs': Tuple[typehints.List[int], ...],
          '__unknown__keywords': typehints.Dict[Any, Any]
      },
                       getcallargs_forhints(str.join, str, typehints.List[int]))
    else:
      self.assertEqual({'self': str}, getcallargs_forhints(str.upper, str))
      # str.strip has an optional second argument.
      self.assertEqual({
          'self': str, 'chars': Any
      },
                       getcallargs_forhints(str.strip, str))
      self.assertEqual({
          'self': str, 'iterable': typehints.List[int]
      },
                       getcallargs_forhints(str.join, str, typehints.List[int]))


class TestGetYieldedType(unittest.TestCase):
  def test_iterables(self):
    self.assertEqual(int, typehints.get_yielded_type(typehints.Iterable[int]))
    self.assertEqual(int, typehints.get_yielded_type(typehints.Iterator[int]))
    self.assertEqual(int, typehints.get_yielded_type(typehints.Generator[int]))
    self.assertEqual(int, typehints.get_yielded_type(typehints.List[int]))
    self.assertEqual(
        typehints.Union[int, str],
        typehints.get_yielded_type(typehints.Tuple[int, str]))
    self.assertEqual(int, typehints.get_yielded_type(typehints.Set[int]))
    self.assertEqual(int, typehints.get_yielded_type(typehints.FrozenSet[int]))

  def test_not_iterable(self):
    with self.assertRaisesRegex(ValueError, r'not iterable'):
      typehints.get_yielded_type(int)


class TestCoerceToKvType(TypeHintTestCase):
  def test_coercion_success(self):
    cases = [
        ((Any, ), typehints.KV[Any, Any]),
        ((typehints.KV[Any, Any], ), typehints.KV[Any, Any]),
        ((typehints.Tuple[str, int], ), typehints.KV[str, int]),
    ]
    for args, expected in cases:
      self.assertEqual(typehints.coerce_to_kv_type(*args), expected)
      self.assertCompatible(args[0], expected)

  def test_coercion_fail(self):
    cases = [
        ((str, 'label', 'producer'), r'producer.*compatible'),
        ((Tuple[str], ), r'two components'),
        # It seems that the only Unions that may be successfully coerced are not
        # Unions but Any (e.g. Union[Any, Tuple[Any, Any]] is Any).
        ((Union[str, int], ), r'compatible'),
        ((Union, ), r'compatible'),
        ((typehints.List[Any], ), r'compatible'),
    ]
    for args, regex in cases:
      with self.assertRaisesRegex(ValueError, regex):
        typehints.coerce_to_kv_type(*args)


class TestParDoAnnotations(unittest.TestCase):
  def test_with_side_input(self):
    class MyDoFn(DoFn):
      def process(self, element: float, side_input: str) -> \
          Iterable[KV[str, float]]:
        pass

    th = MyDoFn().get_type_hints()
    self.assertEqual(th.input_types, ((float, str), {}))
    self.assertEqual(th.output_types, ((KV[str, float], ), {}))

  def test_pep484_annotations(self):
    class MyDoFn(DoFn):
      def process(self, element: int) -> Iterable[str]:
        pass

    th = MyDoFn().get_type_hints()
    self.assertEqual(th.input_types, ((int, ), {}))
    self.assertEqual(th.output_types, ((str, ), {}))


class TestPTransformAnnotations(unittest.TestCase):
  def test_pep484_annotations(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll: PCollection[int]) -> PCollection[str]:
        return pcoll | Map(lambda num: str(num))

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((int, ), {}))
    self.assertEqual(th.output_types, ((str, ), {}))

  def test_annotations_without_input_pcollection_wrapper(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll: int) -> PCollection[str]:
        return pcoll | Map(lambda num: str(num))

    error_str = (
        r'This input type hint will be ignored and not used for '
        r'type-checking purposes. Typically, input type hints for a '
        r'PTransform are single (or nested) types wrapped by a '
        r'PCollection, or PBegin. Got: {} instead.'.format(int))

    with self.assertLogs(level='WARN') as log:
      MyPTransform().get_type_hints()
      self.assertIn(error_str, log.output[0])

  def test_annotations_without_output_pcollection_wrapper(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll: PCollection[int]) -> str:
        return pcoll | Map(lambda num: str(num))

    error_str = (
        r'This output type hint will be ignored and not used for '
        r'type-checking purposes. Typically, output type hints for a '
        r'PTransform are single (or nested) types wrapped by a '
        r'PCollection, PDone, or None. Got: {} instead.'.format(str))

    with self.assertLogs(level='WARN') as log:
      th = MyPTransform().get_type_hints()
      self.assertIn(error_str, log.output[0])
      self.assertEqual(th.input_types, ((int, ), {}))
      self.assertEqual(th.output_types, None)

  def test_annotations_without_input_internal_type(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll: PCollection) -> PCollection[str]:
        return pcoll | Map(lambda num: str(num))

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((Any, ), {}))
    self.assertEqual(th.output_types, ((str, ), {}))

  def test_annotations_without_output_internal_type(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll: PCollection[int]) -> PCollection:
        return pcoll | Map(lambda num: str(num))

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((int, ), {}))
    self.assertEqual(th.output_types, ((Any, ), {}))

  def test_annotations_without_any_internal_type(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll: PCollection) -> PCollection:
        return pcoll | Map(lambda num: str(num))

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((Any, ), {}))
    self.assertEqual(th.output_types, ((Any, ), {}))

  def test_annotations_without_input_typehint(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll) -> PCollection[str]:
        return pcoll | Map(lambda num: str(num))

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((Any, ), {}))
    self.assertEqual(th.output_types, ((str, ), {}))

  def test_annotations_without_output_typehint(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll: PCollection[int]):
        return pcoll | Map(lambda num: str(num))

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((int, ), {}))
    self.assertEqual(th.output_types, ((Any, ), {}))

  def test_annotations_without_any_typehints(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll):
        return pcoll | Map(lambda num: str(num))

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, None)
    self.assertEqual(th.output_types, None)

  def test_annotations_with_pbegin(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll: PBegin):
        return pcoll | Map(lambda num: str(num))

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((Any, ), {}))
    self.assertEqual(th.output_types, ((Any, ), {}))

  def test_annotations_with_pdone(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll) -> PDone:
        return pcoll | Map(lambda num: str(num))

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((Any, ), {}))
    self.assertEqual(th.output_types, ((Any, ), {}))

  def test_annotations_with_none_input(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll: None) -> PCollection[str]:
        return pcoll | Map(lambda num: str(num))

    error_str = (
        r'This input type hint will be ignored and not used for '
        r'type-checking purposes. Typically, input type hints for a '
        r'PTransform are single (or nested) types wrapped by a '
        r'PCollection, or PBegin. Got: {} instead.'.format(None))

    with self.assertLogs(level='WARN') as log:
      th = MyPTransform().get_type_hints()
      self.assertIn(error_str, log.output[0])
      self.assertEqual(th.input_types, None)
      self.assertEqual(th.output_types, ((str, ), {}))

  def test_annotations_with_none_output(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll) -> None:
        return pcoll | Map(lambda num: str(num))

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((Any, ), {}))
    self.assertEqual(th.output_types, ((Any, ), {}))

  def test_annotations_with_arbitrary_output(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll) -> str:
        return pcoll | Map(lambda num: str(num))

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((Any, ), {}))
    self.assertEqual(th.output_types, None)

  def test_annotations_with_arbitrary_input_and_output(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll: int) -> str:
        return pcoll | Map(lambda num: str(num))

    input_error_str = (
        r'This input type hint will be ignored and not used for '
        r'type-checking purposes. Typically, input type hints for a '
        r'PTransform are single (or nested) types wrapped by a '
        r'PCollection, or PBegin. Got: {} instead.'.format(int))

    output_error_str = (
        r'This output type hint will be ignored and not used for '
        r'type-checking purposes. Typically, output type hints for a '
        r'PTransform are single (or nested) types wrapped by a '
        r'PCollection, PDone, or None. Got: {} instead.'.format(str))

    with self.assertLogs(level='WARN') as log:
      th = MyPTransform().get_type_hints()
      self.assertIn(input_error_str, log.output[0])
      self.assertIn(output_error_str, log.output[1])
      self.assertEqual(th.input_types, None)
      self.assertEqual(th.output_types, None)

  def test_typing_module_annotations_are_converted_to_beam_annotations(self):
    class MyPTransform(PTransform):
      def expand(
          self, pcoll: PCollection[typing.Dict[str, str]]
      ) -> PCollection[typing.Dict[str, str]]:
        return pcoll

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((typehints.Dict[str, str], ), {}))
    self.assertEqual(th.input_types, ((typehints.Dict[str, str], ), {}))

  def test_nested_typing_annotations_are_converted_to_beam_annotations(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll:
         PCollection[typing.Union[int, typing.Any, typing.Dict[str, float]]]) \
      -> PCollection[typing.Union[int, typing.Any, typing.Dict[str, float]]]:
        return pcoll

    th = MyPTransform().get_type_hints()
    self.assertEqual(
        th.input_types,
        ((typehints.Union[int, typehints.Any, typehints.Dict[str,
                                                             float]], ), {}))
    self.assertEqual(
        th.input_types,
        ((typehints.Union[int, typehints.Any, typehints.Dict[str,
                                                             float]], ), {}))

  def test_mixed_annotations_are_converted_to_beam_annotations(self):
    class MyPTransform(PTransform):
      def expand(self, pcoll: typing.Any) -> typehints.Any:
        return pcoll

    th = MyPTransform().get_type_hints()
    self.assertEqual(th.input_types, ((typehints.Any, ), {}))
    self.assertEqual(th.input_types, ((typehints.Any, ), {}))


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