Added support for type checking AbstractSet

Fixes #13.

docs/index.rst

@@ -194,22 +194,22 @@ Supported typing.* types
 
 The following types from the ``typing`` package have specialized support:
 
-============== ============================================================
-Type           Notes
-============== ============================================================
-``Callable``   Argument count is checked but types are not (yet)
-``Dict``       Keys and values are typechecked
-``List``       Contents are typechecked
+=============== =============================================================
+Type            Notes
+=============== =============================================================
+``AbstractSet`` Contents are typechecked
+``Callable``    Argument count is checked but types are not (yet)
+``Dict``        Keys and values are typechecked
+``List``        Contents are typechecked
 ``Literal``
-``NamedTuple`` Field values are typechecked
-``Protocol``   Value type checked with ``issubclass()`` against the
-               protocol
-``Set``        Contents are typechecked
-``Sequence``   Contents are typechecked
-``Tuple``      Contents are typechecked
+``NamedTuple``  Field values are typechecked
+``Protocol``    Value type checked with ``issubclass()`` against the protocol
+``Set``         Contents are typechecked
+``Sequence``    Contents are typechecked
+``Tuple``       Contents are typechecked
 ``Type``
-``TypedDict``  Contents are typechecked
-``TypeVar``    Constraints, bound types and co/contravariance are supported
-               but custom generic types are not (due to type erasure)
+``TypedDict``   Contents are typechecked
+``TypeVar``     Constraints, bound types and co/contravariance are supported
+                but custom generic types are not (due to type erasure)
 ``Union``
-============== ============================================================
+=============== =============================================================

docs/versionhistory.rst

@@ -6,6 +6,7 @@ This library adheres to `Semantic Versioning 2.0 <https://semver.org/#semantic-v
 **UNRELEASED**
 
 - Added support for ``typing.Protocol`` subclasses
+- Added support for ``typing.AbstractSet``
 - Fixed the handling of ``total=False`` in ``TypedDict``
 - Removed support of default values in ``TypedDict``, as they are not supported in the spec
 

tests/test_typeguard.py

@@ -6,7 +6,7 @@
 from io import StringIO, BytesIO
 from typing import (
     Any, Callable, Dict, List, Set, Tuple, Union, TypeVar, Sequence, NamedTuple, Iterable,
-    Container, Generic, BinaryIO, TextIO, Generator, Iterator, SupportsInt)
+    Container, Generic, BinaryIO, TextIO, Generator, Iterator, SupportsInt, AbstractSet)
 
 import pytest
 
@@ -275,13 +275,44 @@ def foo(a: Sequence[int]):
         assert str(exc.value) == (
             'type of argument "a"[2] must be int; got str instead')
 
+    def test_abstractset_custom_type(self):
+        class DummySet(AbstractSet[int]):
+            def __contains__(self, x: object) -> bool:
+                return x == 1
+
+            def __len__(self) -> int:
+                return 1
+
+            def __iter__(self) -> Iterator[int]:
+                yield 1
+
+        def foo(a: AbstractSet[int]):
+            assert check_argument_types()
+
+        foo(DummySet())
+
+    def test_abstractset_bad_type(self):
+        def foo(a: AbstractSet[int]):
+            assert check_argument_types()
+
+        exc = pytest.raises(TypeError, foo, 5)
+        assert str(exc.value) == 'type of argument "a" must be a set; got int instead'
+
     def test_set_bad_type(self):
         def foo(a: Set[int]):
             assert check_argument_types()
 
         exc = pytest.raises(TypeError, foo, 5)
         assert str(exc.value) == 'type of argument "a" must be a set; got int instead'
 
+    def test_abstractset_bad_element(self):
+        def foo(a: AbstractSet[int]):
+            assert check_argument_types()
+
+        exc = pytest.raises(TypeError, foo, {1, 2, 'bb'})
+        assert str(exc.value) == (
+            'type of elements of argument "a" must be int; got str instead')
+
     def test_set_bad_element(self):
         def foo(a: Set[int]):
             assert check_argument_types()
@@ -734,8 +765,9 @@ def foo(a: typehint):
         (List, ['x', 6]),
         (Sequence, ['x', 6]),
         (Set, {'x', 6}),
+        (AbstractSet, {'x', 6}),
         (Tuple, ('x', 6)),
-    ], ids=['dict', 'list', 'sequence', 'set', 'tuple'])
+    ], ids=['dict', 'list', 'sequence', 'set', 'abstractset', 'tuple'])
     def test_unparametrized_types_mixed_values(self, typehint, value):
         @typechecked
         def foo(a: typehint):
@@ -783,10 +815,12 @@ def foo(a: typehint):
         foo(value)
 
     @pytest.mark.parametrize('typehint', [
+        AbstractSet[int],
+        AbstractSet,
         Set[int],
         Set,
         set
-    ], ids=['parametrized', 'unparametrized', 'plain'])
+    ], ids=['abstract_parametrized', 'abstract', 'parametrized', 'unparametrized', 'plain'])
     @pytest.mark.parametrize('value', [set(), {6}])
     def test_set(self, typehint, value):
         @typechecked

typeguard/__init__.py

@@ -16,7 +16,7 @@
 from typing import (
     Callable, Any, Union, Dict, List, TypeVar, Tuple, Set, Sequence, get_type_hints, TextIO,
     Optional, IO, BinaryIO, Type, Generator, overload, Iterable, AsyncIterable, Iterator,
-    AsyncIterator)
+    AsyncIterator, AbstractSet)
 from warnings import warn
 from weakref import WeakKeyDictionary, WeakValueDictionary
 
@@ -494,6 +494,7 @@ def check_protocol(argname: str, value, expected_type):
 
 # Equality checks are applied to these
 origin_type_checkers = {
+    AbstractSet: check_set,
     Callable: check_callable,
     collections.abc.Callable: check_callable,
     dict: check_dict,