ext/pybind11/tests/test_methods_and_attributes.py - testing/jenkins-gem5-prod - Git at Google

 import pytest
 from pybind11_tests import methods_and_attributes as m
 from pybind11_tests import ConstructorStats


 def test_methods_and_attributes():
     instance1 = m.ExampleMandA()
     instance2 = m.ExampleMandA(32)

     instance1.add1(instance2)
     instance1.add2(instance2)
     instance1.add3(instance2)
     instance1.add4(instance2)
     instance1.add5(instance2)
     instance1.add6(32)
     instance1.add7(32)
     instance1.add8(32)
     instance1.add9(32)
     instance1.add10(32)

     assert str(instance1) == "ExampleMandA[value=320]"
     assert str(instance2) == "ExampleMandA[value=32]"
     assert str(instance1.self1()) == "ExampleMandA[value=320]"
     assert str(instance1.self2()) == "ExampleMandA[value=320]"
     assert str(instance1.self3()) == "ExampleMandA[value=320]"
     assert str(instance1.self4()) == "ExampleMandA[value=320]"
     assert str(instance1.self5()) == "ExampleMandA[value=320]"

     assert instance1.internal1() == 320
     assert instance1.internal2() == 320
     assert instance1.internal3() == 320
     assert instance1.internal4() == 320
     assert instance1.internal5() == 320

     assert instance1.overloaded() == "()"
     assert instance1.overloaded(0) == "(int)"
     assert instance1.overloaded(1, 1.0) == "(int, float)"
     assert instance1.overloaded(2.0, 2) == "(float, int)"
     assert instance1.overloaded(3,   3) == "(int, int)"
     assert instance1.overloaded(4., 4.) == "(float, float)"
     assert instance1.overloaded_const(-3) == "(int) const"
     assert instance1.overloaded_const(5, 5.0) == "(int, float) const"
     assert instance1.overloaded_const(6.0, 6) == "(float, int) const"
     assert instance1.overloaded_const(7,   7) == "(int, int) const"
     assert instance1.overloaded_const(8., 8.) == "(float, float) const"
     assert instance1.overloaded_float(1, 1) == "(float, float)"
     assert instance1.overloaded_float(1, 1.) == "(float, float)"
     assert instance1.overloaded_float(1., 1) == "(float, float)"
     assert instance1.overloaded_float(1., 1.) == "(float, float)"

     assert instance1.value == 320
     instance1.value = 100
     assert str(instance1) == "ExampleMandA[value=100]"

     cstats = ConstructorStats.get(m.ExampleMandA)
     assert cstats.alive() == 2
     del instance1, instance2
     assert cstats.alive() == 0
     assert cstats.values() == ["32"]
     assert cstats.default_constructions == 1
     assert cstats.copy_constructions == 3
     assert cstats.move_constructions >= 1
     assert cstats.copy_assignments == 0
     assert cstats.move_assignments == 0


 def test_copy_method():
     """Issue #443: calling copied methods fails in Python 3"""

     m.ExampleMandA.add2c = m.ExampleMandA.add2
     m.ExampleMandA.add2d = m.ExampleMandA.add2b
     a = m.ExampleMandA(123)
     assert a.value == 123
     a.add2(m.ExampleMandA(-100))
     assert a.value == 23
     a.add2b(m.ExampleMandA(20))
     assert a.value == 43
     a.add2c(m.ExampleMandA(6))
     assert a.value == 49
     a.add2d(m.ExampleMandA(-7))
     assert a.value == 42


 def test_properties():
     instance = m.TestProperties()

     assert instance.def_readonly == 1
     with pytest.raises(AttributeError):
         instance.def_readonly = 2

     instance.def_readwrite = 2
     assert instance.def_readwrite == 2

     assert instance.def_property_readonly == 2
     with pytest.raises(AttributeError):
         instance.def_property_readonly = 3

     instance.def_property = 3
     assert instance.def_property == 3


 def test_static_properties():
     assert m.TestProperties.def_readonly_static == 1
     with pytest.raises(AttributeError) as excinfo:
         m.TestProperties.def_readonly_static = 2
     assert "can't set attribute" in str(excinfo)

     m.TestProperties.def_readwrite_static = 2
     assert m.TestProperties.def_readwrite_static == 2

     assert m.TestProperties.def_property_readonly_static == 2
     with pytest.raises(AttributeError) as excinfo:
         m.TestProperties.def_property_readonly_static = 3
     assert "can't set attribute" in str(excinfo)

     m.TestProperties.def_property_static = 3
     assert m.TestProperties.def_property_static == 3

     # Static property read and write via instance
     instance = m.TestProperties()

     m.TestProperties.def_readwrite_static = 0
     assert m.TestProperties.def_readwrite_static == 0
     assert instance.def_readwrite_static == 0

     instance.def_readwrite_static = 2
     assert m.TestProperties.def_readwrite_static == 2
     assert instance.def_readwrite_static == 2

     # It should be possible to override properties in derived classes
     assert m.TestPropertiesOverride().def_readonly == 99
     assert m.TestPropertiesOverride.def_readonly_static == 99


 def test_static_cls():
     """Static property getter and setters expect the type object as the their only argument"""

     instance = m.TestProperties()
     assert m.TestProperties.static_cls is m.TestProperties
     assert instance.static_cls is m.TestProperties

     def check_self(self):
         assert self is m.TestProperties

     m.TestProperties.static_cls = check_self
     instance.static_cls = check_self


 def test_metaclass_override():
     """Overriding pybind11's default metaclass changes the behavior of `static_property`"""

     assert type(m.ExampleMandA).__name__ == "pybind11_type"
     assert type(m.MetaclassOverride).__name__ == "type"

     assert m.MetaclassOverride.readonly == 1
     assert type(m.MetaclassOverride.__dict__["readonly"]).__name__ == "pybind11_static_property"

     # Regular `type` replaces the property instead of calling `__set__()`
     m.MetaclassOverride.readonly = 2
     assert m.MetaclassOverride.readonly == 2
     assert isinstance(m.MetaclassOverride.__dict__["readonly"], int)


 def test_no_mixed_overloads():
     from pybind11_tests import debug_enabled

     with pytest.raises(RuntimeError) as excinfo:
         m.ExampleMandA.add_mixed_overloads1()
     assert (str(excinfo.value) ==
             "overloading a method with both static and instance methods is not supported; " +
             ("compile in debug mode for more details" if not debug_enabled else
              "error while attempting to bind static method ExampleMandA.overload_mixed1"
              "(arg0: float) -> str")
             )

     with pytest.raises(RuntimeError) as excinfo:
         m.ExampleMandA.add_mixed_overloads2()
     assert (str(excinfo.value) ==
             "overloading a method with both static and instance methods is not supported; " +
             ("compile in debug mode for more details" if not debug_enabled else
              "error while attempting to bind instance method ExampleMandA.overload_mixed2"
              "(self: pybind11_tests.methods_and_attributes.ExampleMandA, arg0: int, arg1: int)"
              " -> str")
             )


 @pytest.mark.parametrize("access", ["ro", "rw", "static_ro", "static_rw"])
 def test_property_return_value_policies(access):
     if not access.startswith("static"):
         obj = m.TestPropRVP()
     else:
         obj = m.TestPropRVP

     ref = getattr(obj, access + "_ref")
     assert ref.value == 1
     ref.value = 2
     assert getattr(obj, access + "_ref").value == 2
     ref.value = 1  # restore original value for static properties

     copy = getattr(obj, access + "_copy")
     assert copy.value == 1
     copy.value = 2
     assert getattr(obj, access + "_copy").value == 1

     copy = getattr(obj, access + "_func")
     assert copy.value == 1
     copy.value = 2
     assert getattr(obj, access + "_func").value == 1


 def test_property_rvalue_policy():
     """When returning an rvalue, the return value policy is automatically changed from
     `reference(_internal)` to `move`. The following would not work otherwise."""

     instance = m.TestPropRVP()
     o = instance.rvalue
     assert o.value == 1

     os = m.TestPropRVP.static_rvalue
     assert os.value == 1


 # https://bitbucket.org/pypy/pypy/issues/2447
 @pytest.unsupported_on_pypy
 def test_dynamic_attributes():
     instance = m.DynamicClass()
     assert not hasattr(instance, "foo")
     assert "foo" not in dir(instance)

     # Dynamically add attribute
     instance.foo = 42
     assert hasattr(instance, "foo")
     assert instance.foo == 42
     assert "foo" in dir(instance)

     # __dict__ should be accessible and replaceable
     assert "foo" in instance.__dict__
     instance.__dict__ = {"bar": True}
     assert not hasattr(instance, "foo")
     assert hasattr(instance, "bar")

     with pytest.raises(TypeError) as excinfo:
         instance.__dict__ = []
     assert str(excinfo.value) == "__dict__ must be set to a dictionary, not a 'list'"

     cstats = ConstructorStats.get(m.DynamicClass)
     assert cstats.alive() == 1
     del instance
     assert cstats.alive() == 0

     # Derived classes should work as well
     class PythonDerivedDynamicClass(m.DynamicClass):
         pass

     for cls in m.CppDerivedDynamicClass, PythonDerivedDynamicClass:
         derived = cls()
         derived.foobar = 100
         assert derived.foobar == 100

         assert cstats.alive() == 1
         del derived
         assert cstats.alive() == 0


 # https://bitbucket.org/pypy/pypy/issues/2447
 @pytest.unsupported_on_pypy
 def test_cyclic_gc():
     # One object references itself
     instance = m.DynamicClass()
     instance.circular_reference = instance

     cstats = ConstructorStats.get(m.DynamicClass)
     assert cstats.alive() == 1
     del instance
     assert cstats.alive() == 0

     # Two object reference each other
     i1 = m.DynamicClass()
     i2 = m.DynamicClass()
     i1.cycle = i2
     i2.cycle = i1

     assert cstats.alive() == 2
     del i1, i2
     assert cstats.alive() == 0


 def test_noconvert_args(msg):
     a = m.ArgInspector()
     assert msg(a.f("hi")) == """
         loading ArgInspector1 argument WITH conversion allowed.  Argument value = hi
     """
     assert msg(a.g("this is a", "this is b")) == """
         loading ArgInspector1 argument WITHOUT conversion allowed.  Argument value = this is a
         loading ArgInspector1 argument WITH conversion allowed.  Argument value = this is b
         13
         loading ArgInspector2 argument WITH conversion allowed.  Argument value = (default arg inspector 2)
     """  # noqa: E501 line too long
     assert msg(a.g("this is a", "this is b", 42)) == """
         loading ArgInspector1 argument WITHOUT conversion allowed.  Argument value = this is a
         loading ArgInspector1 argument WITH conversion allowed.  Argument value = this is b
         42
         loading ArgInspector2 argument WITH conversion allowed.  Argument value = (default arg inspector 2)
     """  # noqa: E501 line too long
     assert msg(a.g("this is a", "this is b", 42, "this is d")) == """
         loading ArgInspector1 argument WITHOUT conversion allowed.  Argument value = this is a
         loading ArgInspector1 argument WITH conversion allowed.  Argument value = this is b
         42
         loading ArgInspector2 argument WITH conversion allowed.  Argument value = this is d
     """
     assert (a.h("arg 1") ==
             "loading ArgInspector2 argument WITHOUT conversion allowed.  Argument value = arg 1")
     assert msg(m.arg_inspect_func("A1", "A2")) == """
         loading ArgInspector2 argument WITH conversion allowed.  Argument value = A1
         loading ArgInspector1 argument WITHOUT conversion allowed.  Argument value = A2
     """

     assert m.floats_preferred(4) == 2.0
     assert m.floats_only(4.0) == 2.0
     with pytest.raises(TypeError) as excinfo:
         m.floats_only(4)
     assert msg(excinfo.value) == """
         floats_only(): incompatible function arguments. The following argument types are supported:
             1. (f: float) -> float

         Invoked with: 4
     """

     assert m.ints_preferred(4) == 2
     assert m.ints_preferred(True) == 0
     with pytest.raises(TypeError) as excinfo:
         m.ints_preferred(4.0)
     assert msg(excinfo.value) == """
         ints_preferred(): incompatible function arguments. The following argument types are supported:
             1. (i: int) -> int

         Invoked with: 4.0
     """  # noqa: E501 line too long

     assert m.ints_only(4) == 2
     with pytest.raises(TypeError) as excinfo:
         m.ints_only(4.0)
     assert msg(excinfo.value) == """
         ints_only(): incompatible function arguments. The following argument types are supported:
             1. (i: int) -> int

         Invoked with: 4.0
     """


 def test_bad_arg_default(msg):
     from pybind11_tests import debug_enabled

     with pytest.raises(RuntimeError) as excinfo:
         m.bad_arg_def_named()
     assert msg(excinfo.value) == (
         "arg(): could not convert default argument 'a: UnregisteredType' in function "
         "'should_fail' into a Python object (type not registered yet?)"
         if debug_enabled else
         "arg(): could not convert default argument into a Python object (type not registered "
         "yet?). Compile in debug mode for more information."
     )

     with pytest.raises(RuntimeError) as excinfo:
         m.bad_arg_def_unnamed()
     assert msg(excinfo.value) == (
         "arg(): could not convert default argument 'UnregisteredType' in function "
         "'should_fail' into a Python object (type not registered yet?)"
         if debug_enabled else
         "arg(): could not convert default argument into a Python object (type not registered "
         "yet?). Compile in debug mode for more information."
     )


 def test_accepts_none(msg):
     a = m.NoneTester()
     assert m.no_none1(a) == 42
     assert m.no_none2(a) == 42
     assert m.no_none3(a) == 42
     assert m.no_none4(a) == 42
     assert m.no_none5(a) == 42
     assert m.ok_none1(a) == 42
     assert m.ok_none2(a) == 42
     assert m.ok_none3(a) == 42
     assert m.ok_none4(a) == 42
     assert m.ok_none5(a) == 42

     with pytest.raises(TypeError) as excinfo:
         m.no_none1(None)
     assert "incompatible function arguments" in str(excinfo.value)
     with pytest.raises(TypeError) as excinfo:
         m.no_none2(None)
     assert "incompatible function arguments" in str(excinfo.value)
     with pytest.raises(TypeError) as excinfo:
         m.no_none3(None)
     assert "incompatible function arguments" in str(excinfo.value)
     with pytest.raises(TypeError) as excinfo:
         m.no_none4(None)
     assert "incompatible function arguments" in str(excinfo.value)
     with pytest.raises(TypeError) as excinfo:
         m.no_none5(None)
     assert "incompatible function arguments" in str(excinfo.value)

     # The first one still raises because you can't pass None as a lvalue reference arg:
     with pytest.raises(TypeError) as excinfo:
         assert m.ok_none1(None) == -1
     assert msg(excinfo.value) == """
         ok_none1(): incompatible function arguments. The following argument types are supported:
             1. (arg0: m.methods_and_attributes.NoneTester) -> int

         Invoked with: None
     """

     # The rest take the argument as pointer or holder, and accept None:
     assert m.ok_none2(None) == -1
     assert m.ok_none3(None) == -1
     assert m.ok_none4(None) == -1
     assert m.ok_none5(None) == -1


 def test_str_issue(msg):
     """#283: __str__ called on uninitialized instance when constructor arguments invalid"""

     assert str(m.StrIssue(3)) == "StrIssue[3]"

     with pytest.raises(TypeError) as excinfo:
         str(m.StrIssue("no", "such", "constructor"))
     assert msg(excinfo.value) == """
         __init__(): incompatible constructor arguments. The following argument types are supported:
             1. m.methods_and_attributes.StrIssue(arg0: int)
             2. m.methods_and_attributes.StrIssue()

         Invoked with: 'no', 'such', 'constructor'
     """


 def test_unregistered_base_implementations():
     a = m.RegisteredDerived()
     a.do_nothing()
     assert a.rw_value == 42
     assert a.ro_value == 1.25
     a.rw_value += 5
     assert a.sum() == 48.25
     a.increase_value()
     assert a.rw_value == 48
     assert a.ro_value == 1.5
     assert a.sum() == 49.5
     assert a.rw_value_prop == 48
     a.rw_value_prop += 1
     assert a.rw_value_prop == 49
     a.increase_value()
     assert a.ro_value_prop == 1.75


 def test_custom_caster_destruction():
     """Tests that returning a pointer to a type that gets converted with a custom type caster gets
     destroyed when the function has py::return_value_policy::take_ownership policy applied."""

     cstats = m.destruction_tester_cstats()
     # This one *doesn't* have take_ownership: the pointer should be used but not destroyed:
     z = m.custom_caster_no_destroy()
     assert cstats.alive() == 1 and cstats.default_constructions == 1
     assert z

     # take_ownership applied: this constructs a new object, casts it, then destroys it:
     z = m.custom_caster_destroy()
     assert z
     assert cstats.default_constructions == 2

     # Same, but with a const pointer return (which should *not* inhibit destruction):
     z = m.custom_caster_destroy_const()
     assert z
     assert cstats.default_constructions == 3

     # Make sure we still only have the original object (from ..._no_destroy()) alive:
     assert cstats.alive() == 1
	import pytest
	from pybind11_tests import methods_and_attributes as m
	from pybind11_tests import ConstructorStats


	def test_methods_and_attributes():
	instance1 = m.ExampleMandA()
	instance2 = m.ExampleMandA(32)

	instance1.add1(instance2)
	instance1.add2(instance2)
	instance1.add3(instance2)
	instance1.add4(instance2)
	instance1.add5(instance2)
	instance1.add6(32)
	instance1.add7(32)
	instance1.add8(32)
	instance1.add9(32)
	instance1.add10(32)

	assert str(instance1) == "ExampleMandA[value=320]"
	assert str(instance2) == "ExampleMandA[value=32]"
	assert str(instance1.self1()) == "ExampleMandA[value=320]"
	assert str(instance1.self2()) == "ExampleMandA[value=320]"
	assert str(instance1.self3()) == "ExampleMandA[value=320]"
	assert str(instance1.self4()) == "ExampleMandA[value=320]"
	assert str(instance1.self5()) == "ExampleMandA[value=320]"

	assert instance1.internal1() == 320
	assert instance1.internal2() == 320
	assert instance1.internal3() == 320
	assert instance1.internal4() == 320
	assert instance1.internal5() == 320

	assert instance1.overloaded() == "()"
	assert instance1.overloaded(0) == "(int)"
	assert instance1.overloaded(1, 1.0) == "(int, float)"
	assert instance1.overloaded(2.0, 2) == "(float, int)"
	assert instance1.overloaded(3, 3) == "(int, int)"
	assert instance1.overloaded(4., 4.) == "(float, float)"
	assert instance1.overloaded_const(-3) == "(int) const"
	assert instance1.overloaded_const(5, 5.0) == "(int, float) const"
	assert instance1.overloaded_const(6.0, 6) == "(float, int) const"
	assert instance1.overloaded_const(7, 7) == "(int, int) const"
	assert instance1.overloaded_const(8., 8.) == "(float, float) const"
	assert instance1.overloaded_float(1, 1) == "(float, float)"
	assert instance1.overloaded_float(1, 1.) == "(float, float)"
	assert instance1.overloaded_float(1., 1) == "(float, float)"
	assert instance1.overloaded_float(1., 1.) == "(float, float)"

	assert instance1.value == 320
	instance1.value = 100
	assert str(instance1) == "ExampleMandA[value=100]"

	cstats = ConstructorStats.get(m.ExampleMandA)
	assert cstats.alive() == 2
	del instance1, instance2
	assert cstats.alive() == 0
	assert cstats.values() == ["32"]
	assert cstats.default_constructions == 1
	assert cstats.copy_constructions == 3
	assert cstats.move_constructions >= 1
	assert cstats.copy_assignments == 0
	assert cstats.move_assignments == 0


	def test_copy_method():
	"""Issue #443: calling copied methods fails in Python 3"""

	m.ExampleMandA.add2c = m.ExampleMandA.add2
	m.ExampleMandA.add2d = m.ExampleMandA.add2b
	a = m.ExampleMandA(123)
	assert a.value == 123
	a.add2(m.ExampleMandA(-100))
	assert a.value == 23
	a.add2b(m.ExampleMandA(20))
	assert a.value == 43
	a.add2c(m.ExampleMandA(6))
	assert a.value == 49
	a.add2d(m.ExampleMandA(-7))
	assert a.value == 42


	def test_properties():
	instance = m.TestProperties()

	assert instance.def_readonly == 1
	with pytest.raises(AttributeError):
	instance.def_readonly = 2

	instance.def_readwrite = 2
	assert instance.def_readwrite == 2

	assert instance.def_property_readonly == 2
	with pytest.raises(AttributeError):
	instance.def_property_readonly = 3

	instance.def_property = 3
	assert instance.def_property == 3


	def test_static_properties():
	assert m.TestProperties.def_readonly_static == 1
	with pytest.raises(AttributeError) as excinfo:
	m.TestProperties.def_readonly_static = 2
	assert "can't set attribute" in str(excinfo)

	m.TestProperties.def_readwrite_static = 2
	assert m.TestProperties.def_readwrite_static == 2

	assert m.TestProperties.def_property_readonly_static == 2
	with pytest.raises(AttributeError) as excinfo:
	m.TestProperties.def_property_readonly_static = 3
	assert "can't set attribute" in str(excinfo)

	m.TestProperties.def_property_static = 3
	assert m.TestProperties.def_property_static == 3

	# Static property read and write via instance
	instance = m.TestProperties()

	m.TestProperties.def_readwrite_static = 0
	assert m.TestProperties.def_readwrite_static == 0
	assert instance.def_readwrite_static == 0

	instance.def_readwrite_static = 2
	assert m.TestProperties.def_readwrite_static == 2
	assert instance.def_readwrite_static == 2

	# It should be possible to override properties in derived classes
	assert m.TestPropertiesOverride().def_readonly == 99
	assert m.TestPropertiesOverride.def_readonly_static == 99


	def test_static_cls():
	"""Static property getter and setters expect the type object as the their only argument"""

	instance = m.TestProperties()
	assert m.TestProperties.static_cls is m.TestProperties
	assert instance.static_cls is m.TestProperties

	def check_self(self):
	assert self is m.TestProperties

	m.TestProperties.static_cls = check_self
	instance.static_cls = check_self


	def test_metaclass_override():
	"""Overriding pybind11's default metaclass changes the behavior of `static_property`"""

	assert type(m.ExampleMandA).__name__ == "pybind11_type"
	assert type(m.MetaclassOverride).__name__ == "type"

	assert m.MetaclassOverride.readonly == 1
	assert type(m.MetaclassOverride.__dict__["readonly"]).__name__ == "pybind11_static_property"

	# Regular `type` replaces the property instead of calling `__set__()`
	m.MetaclassOverride.readonly = 2
	assert m.MetaclassOverride.readonly == 2
	assert isinstance(m.MetaclassOverride.__dict__["readonly"], int)


	def test_no_mixed_overloads():
	from pybind11_tests import debug_enabled

	with pytest.raises(RuntimeError) as excinfo:
	m.ExampleMandA.add_mixed_overloads1()
	assert (str(excinfo.value) ==
	"overloading a method with both static and instance methods is not supported; " +
	("compile in debug mode for more details" if not debug_enabled else
	"error while attempting to bind static method ExampleMandA.overload_mixed1"
	"(arg0: float) -> str")
	)

	with pytest.raises(RuntimeError) as excinfo:
	m.ExampleMandA.add_mixed_overloads2()
	assert (str(excinfo.value) ==
	"overloading a method with both static and instance methods is not supported; " +
	("compile in debug mode for more details" if not debug_enabled else
	"error while attempting to bind instance method ExampleMandA.overload_mixed2"
	"(self: pybind11_tests.methods_and_attributes.ExampleMandA, arg0: int, arg1: int)"
	" -> str")
	)


	@pytest.mark.parametrize("access", ["ro", "rw", "static_ro", "static_rw"])
	def test_property_return_value_policies(access):
	if not access.startswith("static"):
	obj = m.TestPropRVP()
	else:
	obj = m.TestPropRVP

	ref = getattr(obj, access + "_ref")
	assert ref.value == 1
	ref.value = 2
	assert getattr(obj, access + "_ref").value == 2
	ref.value = 1 # restore original value for static properties

	copy = getattr(obj, access + "_copy")
	assert copy.value == 1
	copy.value = 2
	assert getattr(obj, access + "_copy").value == 1

	copy = getattr(obj, access + "_func")
	assert copy.value == 1
	copy.value = 2
	assert getattr(obj, access + "_func").value == 1


	def test_property_rvalue_policy():
	"""When returning an rvalue, the return value policy is automatically changed from
	`reference(_internal)` to `move`. The following would not work otherwise."""

	instance = m.TestPropRVP()
	o = instance.rvalue
	assert o.value == 1

	os = m.TestPropRVP.static_rvalue
	assert os.value == 1


	# https://bitbucket.org/pypy/pypy/issues/2447
	@pytest.unsupported_on_pypy
	def test_dynamic_attributes():
	instance = m.DynamicClass()
	assert not hasattr(instance, "foo")
	assert "foo" not in dir(instance)

	# Dynamically add attribute
	instance.foo = 42
	assert hasattr(instance, "foo")
	assert instance.foo == 42
	assert "foo" in dir(instance)

	# __dict__ should be accessible and replaceable
	assert "foo" in instance.__dict__
	instance.__dict__ = {"bar": True}
	assert not hasattr(instance, "foo")
	assert hasattr(instance, "bar")

	with pytest.raises(TypeError) as excinfo:
	instance.__dict__ = []
	assert str(excinfo.value) == "__dict__ must be set to a dictionary, not a 'list'"

	cstats = ConstructorStats.get(m.DynamicClass)
	assert cstats.alive() == 1
	del instance
	assert cstats.alive() == 0

	# Derived classes should work as well
	class PythonDerivedDynamicClass(m.DynamicClass):
	pass

	for cls in m.CppDerivedDynamicClass, PythonDerivedDynamicClass:
	derived = cls()
	derived.foobar = 100
	assert derived.foobar == 100

	assert cstats.alive() == 1
	del derived
	assert cstats.alive() == 0


	# https://bitbucket.org/pypy/pypy/issues/2447
	@pytest.unsupported_on_pypy
	def test_cyclic_gc():
	# One object references itself
	instance = m.DynamicClass()
	instance.circular_reference = instance

	cstats = ConstructorStats.get(m.DynamicClass)
	assert cstats.alive() == 1
	del instance
	assert cstats.alive() == 0

	# Two object reference each other
	i1 = m.DynamicClass()
	i2 = m.DynamicClass()
	i1.cycle = i2
	i2.cycle = i1

	assert cstats.alive() == 2
	del i1, i2
	assert cstats.alive() == 0


	def test_noconvert_args(msg):
	a = m.ArgInspector()
	assert msg(a.f("hi")) == """
	loading ArgInspector1 argument WITH conversion allowed. Argument value = hi
	"""
	assert msg(a.g("this is a", "this is b")) == """
	loading ArgInspector1 argument WITHOUT conversion allowed. Argument value = this is a
	loading ArgInspector1 argument WITH conversion allowed. Argument value = this is b
	13
	loading ArgInspector2 argument WITH conversion allowed. Argument value = (default arg inspector 2)
	""" # noqa: E501 line too long
	assert msg(a.g("this is a", "this is b", 42)) == """
	loading ArgInspector1 argument WITHOUT conversion allowed. Argument value = this is a
	loading ArgInspector1 argument WITH conversion allowed. Argument value = this is b
	42
	loading ArgInspector2 argument WITH conversion allowed. Argument value = (default arg inspector 2)
	""" # noqa: E501 line too long
	assert msg(a.g("this is a", "this is b", 42, "this is d")) == """
	loading ArgInspector1 argument WITHOUT conversion allowed. Argument value = this is a
	loading ArgInspector1 argument WITH conversion allowed. Argument value = this is b
	42
	loading ArgInspector2 argument WITH conversion allowed. Argument value = this is d
	"""
	assert (a.h("arg 1") ==
	"loading ArgInspector2 argument WITHOUT conversion allowed. Argument value = arg 1")
	assert msg(m.arg_inspect_func("A1", "A2")) == """
	loading ArgInspector2 argument WITH conversion allowed. Argument value = A1
	loading ArgInspector1 argument WITHOUT conversion allowed. Argument value = A2
	"""

	assert m.floats_preferred(4) == 2.0
	assert m.floats_only(4.0) == 2.0
	with pytest.raises(TypeError) as excinfo:
	m.floats_only(4)
	assert msg(excinfo.value) == """
	floats_only(): incompatible function arguments. The following argument types are supported:
	1. (f: float) -> float

	Invoked with: 4
	"""

	assert m.ints_preferred(4) == 2
	assert m.ints_preferred(True) == 0
	with pytest.raises(TypeError) as excinfo:
	m.ints_preferred(4.0)
	assert msg(excinfo.value) == """
	ints_preferred(): incompatible function arguments. The following argument types are supported:
	1. (i: int) -> int

	Invoked with: 4.0
	""" # noqa: E501 line too long

	assert m.ints_only(4) == 2
	with pytest.raises(TypeError) as excinfo:
	m.ints_only(4.0)
	assert msg(excinfo.value) == """
	ints_only(): incompatible function arguments. The following argument types are supported:
	1. (i: int) -> int

	Invoked with: 4.0
	"""


	def test_bad_arg_default(msg):
	from pybind11_tests import debug_enabled

	with pytest.raises(RuntimeError) as excinfo:
	m.bad_arg_def_named()
	assert msg(excinfo.value) == (
	"arg(): could not convert default argument 'a: UnregisteredType' in function "
	"'should_fail' into a Python object (type not registered yet?)"
	if debug_enabled else
	"arg(): could not convert default argument into a Python object (type not registered "
	"yet?). Compile in debug mode for more information."
	)

	with pytest.raises(RuntimeError) as excinfo:
	m.bad_arg_def_unnamed()
	assert msg(excinfo.value) == (
	"arg(): could not convert default argument 'UnregisteredType' in function "
	"'should_fail' into a Python object (type not registered yet?)"
	if debug_enabled else
	"arg(): could not convert default argument into a Python object (type not registered "
	"yet?). Compile in debug mode for more information."
	)


	def test_accepts_none(msg):
	a = m.NoneTester()
	assert m.no_none1(a) == 42
	assert m.no_none2(a) == 42
	assert m.no_none3(a) == 42
	assert m.no_none4(a) == 42
	assert m.no_none5(a) == 42
	assert m.ok_none1(a) == 42
	assert m.ok_none2(a) == 42
	assert m.ok_none3(a) == 42
	assert m.ok_none4(a) == 42
	assert m.ok_none5(a) == 42

	with pytest.raises(TypeError) as excinfo:
	m.no_none1(None)
	assert "incompatible function arguments" in str(excinfo.value)
	with pytest.raises(TypeError) as excinfo:
	m.no_none2(None)
	assert "incompatible function arguments" in str(excinfo.value)
	with pytest.raises(TypeError) as excinfo:
	m.no_none3(None)
	assert "incompatible function arguments" in str(excinfo.value)
	with pytest.raises(TypeError) as excinfo:
	m.no_none4(None)
	assert "incompatible function arguments" in str(excinfo.value)
	with pytest.raises(TypeError) as excinfo:
	m.no_none5(None)
	assert "incompatible function arguments" in str(excinfo.value)

	# The first one still raises because you can't pass None as a lvalue reference arg:
	with pytest.raises(TypeError) as excinfo:
	assert m.ok_none1(None) == -1
	assert msg(excinfo.value) == """
	ok_none1(): incompatible function arguments. The following argument types are supported:
	1. (arg0: m.methods_and_attributes.NoneTester) -> int

	Invoked with: None
	"""

	# The rest take the argument as pointer or holder, and accept None:
	assert m.ok_none2(None) == -1
	assert m.ok_none3(None) == -1
	assert m.ok_none4(None) == -1
	assert m.ok_none5(None) == -1


	def test_str_issue(msg):
	"""#283: __str__ called on uninitialized instance when constructor arguments invalid"""

	assert str(m.StrIssue(3)) == "StrIssue[3]"

	with pytest.raises(TypeError) as excinfo:
	str(m.StrIssue("no", "such", "constructor"))
	assert msg(excinfo.value) == """
	__init__(): incompatible constructor arguments. The following argument types are supported:
	1. m.methods_and_attributes.StrIssue(arg0: int)
	2. m.methods_and_attributes.StrIssue()

	Invoked with: 'no', 'such', 'constructor'
	"""


	def test_unregistered_base_implementations():
	a = m.RegisteredDerived()
	a.do_nothing()
	assert a.rw_value == 42
	assert a.ro_value == 1.25
	a.rw_value += 5
	assert a.sum() == 48.25
	a.increase_value()
	assert a.rw_value == 48
	assert a.ro_value == 1.5
	assert a.sum() == 49.5
	assert a.rw_value_prop == 48
	a.rw_value_prop += 1
	assert a.rw_value_prop == 49
	a.increase_value()
	assert a.ro_value_prop == 1.75


	def test_custom_caster_destruction():
	"""Tests that returning a pointer to a type that gets converted with a custom type caster gets
	destroyed when the function has py::return_value_policy::take_ownership policy applied."""

	cstats = m.destruction_tester_cstats()
	# This one doesn't have take_ownership: the pointer should be used but not destroyed:
	z = m.custom_caster_no_destroy()
	assert cstats.alive() == 1 and cstats.default_constructions == 1
	assert z

	# take_ownership applied: this constructs a new object, casts it, then destroys it:
	z = m.custom_caster_destroy()
	assert z
	assert cstats.default_constructions == 2

	# Same, but with a const pointer return (which should not inhibit destruction):
	z = m.custom_caster_destroy_const()
	assert z
	assert cstats.default_constructions == 3

	# Make sure we still only have the original object (from ..._no_destroy()) alive:
	assert cstats.alive() == 1