May 5, 2021 · Apr 27, 2021 · Apr 27, 2021 · Apr 28, 2021 · Apr 29, 2021 · Apr 29, 2021
diff --git a/changelog.d/796.change.rst b/changelog.d/796.change.rst
 ``attrs`` has added provisional support for static typing in ``pyright`` version 1.1.135 via the `dataclass_transforms specification <https://github.com/microsoft/pyright/blob/1.1.135/specs/dataclass_transforms.md>`.
 Both the ``pyright`` specification and ``attrs`` implementation may change in future versions of both projects.

 Your constructive feedback is welcome in both `attrs#795 <https://github.com/python-attrs/attrs/issues/795>`_ and `pyright#1782 <https://github.com/microsoft/pyright/discussions/1782>`_.
diff --git a/docs/extending.rst b/docs/extending.rst

 Another common use case is to overwrite ``attrs``'s defaults.

 Unfortunately, this currently `confuses <https://github.com/python/mypy/issues/5406>`_ mypy's ``attrs`` plugin.
 Mypy
 ************

 Unfortunately, decorator wrapping currently `confuses <https://github.com/python/mypy/issues/5406>`_ mypy's ``attrs`` plugin.
 At the moment, the best workaround is to hold your nose, write a fake mypy plugin, and mutate a bunch of global variables::

   from mypy.plugin import Plugin
   Please note that it is currently *impossible* to let mypy know that you've changed defaults like *eq* or *order*.
   You can only use this trick to tell mypy that a class is actually an ``attrs`` class.

 Pyright
 *************

 Generic decorator wrapping is supported in ``pyright`` via the provisional dataclass_transform_ specification.

 For a custom wrapping of the form::

    def custom_define(f):
        return attr.define(f)

 This is implemented via a ``__dataclass_transform__`` type decorator in the custom extension's ``.pyi`` of the form::

    def __dataclass_transform__(
        *,
        eq_default: bool = True,
        order_default: bool = False,
        kw_only_default: bool = False,
        field_descriptors: Tuple[Union[type, Callable[..., Any]], ...] = (()),
    ) -> Callable[[_T], _T]: ...

    @__dataclass_transform__(field_descriptors=(attr.attrib, attr.field))
    def custom_define(f): ...

 .. note::

   ``dataclass_transform`` is supported provisionally as of ``pyright`` 1.1.135.

   Both the ``pyright`` dataclass_transform_ specification and ``attrs`` implementation may changed in future versions.

 Types
 -----
   {'dt': '2020-05-04T13:37:00'}
   >>> json.dumps(data)
   '{"dt": "2020-05-04T13:37:00"}'

 *****

 .. _dataclass_transform: https://github.com/microsoft/pyright/blob/1.1.135/specs/dataclass_transforms.md
diff --git a/docs/types.rst b/docs/types.rst
 When this happens, ``attrs`` will simply put these string literals into the ``type`` attributes.
 If you need to resolve these to real types, you can call `attr.resolve_types` which will update the attribute in place.

 In practice though, types show their biggest usefulness in combination with tools like mypy_orpytype_ that both have dedicated support for ``attrs`` classes.
 In practice though, types show their biggest usefulness in combination with tools like mypy_, pytype_orpyright_ that have dedicated support for ``attrs`` classes.

 The addition of static types is certainly one of the most exciting features in the Python ecosystem and helps you writing *correct* and *verified self-documenting* code.

 If you don't know where to start, Carl Meyer gave a great talk on `Type-checked Python in the Real World <https://www.youtube.com/watch?v=pMgmKJyWKn8>`_ at PyCon US 2018 that will help you to get started in no time.

 mypy
 ----
      a_number = attr.ib(default=42)  # type: int
      list_of_numbers = attr.ib(factory=list, type=typing.List[int])

 *****

 The addition of static types is certainly one of the most exciting features in the Python ecosystem and helps you writing *correct* and *verified self-documenting* code.
 pyright
 -------

 If you don't know where to start, Carl Meyer gave a great talk on `Type-checked Python in the Real World <https://www.youtube.com/watch?v=pMgmKJyWKn8>`_ at PyCon US 2018 that will help you to get started in no time.
 ``attrs`` provides support for pyright_ though the dataclass_transform_ specification.
 This provides static type inference for a subset of ``attrs`` equivalent to standard-library ``dataclasses``,
 and requires explicit type annotations using the :ref:`next-gen` or ``@attr.s(auto_attribs=True)`` API.

 Given the following definition, ``pyright`` will generate static type signatures for ``SomeClass`` attribute access, ``__init__``, ``__eq__``, and comparison methods::

  @attr.define
  class SomeClass(object):
      a_number: int = 42
      list_of_numbers: typing.List[int] = attr.field(factory=list)

 .. note::

   ``dataclass_transform``-based types are supported provisionally as of ``pyright`` 1.1.135 and ``attrs`` 21.1.
   Both the ``pyright`` dataclass_transform_ specification and ``attrs`` implementation may changed in future versions.

   The ``pyright`` inferred types are a subset of those supported by ``mypy``, including:

   - The generated ``__init__`` signature only includes the attribute type annotations,
     and does not include attribute ``converter`` types.

   - The ``attr.frozen`` decorator is not typed with frozen attributes, which are properly typed via ``attr.define(frozen=True)``.

   Your constructive feedback is welcome in both `attrs#795 <https://github.com/python-attrs/attrs/issues/795>`_ and `pyright#1782 <https://github.com/microsoft/pyright/discussions/1782>`_.

 *****

 .. _mypy: http://mypy-lang.org
 .. _pytype: https://google.github.io/pytype/
 .. _pyright: https://github.com/microsoft/pyright
 .. _dataclass_transform: https://github.com/microsoft/pyright/blob/1.1.135/specs/dataclass_transforms.md
diff --git a/src/attr/__init__.pyi b/src/attr/__init__.pyi
        takes_self: bool = ...,
    ) -> _T: ...

 # Static type inference support via __dataclass_transform__ implemented as per:
 # https://github.com/microsoft/pyright/blob/1.1.135/specs/dataclass_transforms.md
 # This annotation must be applied to all overloads of "define" and "attrs"
 #
 # NOTE: This is a typing construct and does not exist at runtime.  Extensions
 # wrapping attrs decorators should declare a separate __dataclass_transform__
 # signature in the extension module using the specification linked above to
 # provide pyright support.
 def __dataclass_transform__(
    *,
    eq_default: bool = True,
    order_default: bool = False,
    kw_only_default: bool = False,
    field_descriptors: Tuple[Union[type, Callable[..., Any]], ...] = (()),
 ) -> Callable[[_T], _T]: ...

 class Attribute(Generic[_T]):
    name: str
    on_setattr: Optional[_OnSetAttrArgType] = ...,
 ) -> Any: ...
 @overload
 @__dataclass_transform__(order_default=True, field_descriptors=(attrib, field))
 def attrs(
    maybe_cls: _C,
    these: Optional[Dict[str, Any]] = ...,
    field_transformer: Optional[_FieldTransformer] = ...,
 ) -> _C: ...
 @overload
 @__dataclass_transform__(order_default=True, field_descriptors=(attrib, field))
 def attrs(
    maybe_cls: None = ...,
    these: Optional[Dict[str, Any]] = ...,
    field_transformer: Optional[_FieldTransformer] = ...,
 ) -> Callable[[_C], _C]: ...
 @overload
 @__dataclass_transform__(field_descriptors=(attrib, field))
 def define(
    maybe_cls: _C,
    *,
    field_transformer: Optional[_FieldTransformer] = ...,
 ) -> _C: ...
 @overload
 @__dataclass_transform__(field_descriptors=(attrib, field))
 def define(
    maybe_cls: None = ...,
    *,
diff --git a/tests/dataclass_transform_example.py b/tests/dataclass_transform_example.py
 import attr


 @attr.define()
 class Define:
    a: str
    b: int


 reveal_type(Define.__init__)  # noqa


 @attr.define()
 class DefineConverter:
    # mypy plugin adapts the "int" method signature, pyright does not
    with_converter: int = attr.field(converter=int)


 reveal_type(DefineConverter.__init__)  # noqa


 # mypy plugin supports attr.frozen, pyright does not
 @attr.frozen()
 class Frozen:
    a: str


 d = Frozen("a")
 d.a = "new"

 reveal_type(d.a)  # noqa


 # but pyright supports attr.define(frozen)
 @attr.define(frozen=True)
 class FrozenDefine:
    a: str


 d2 = FrozenDefine("a")
 d2.a = "new"

 reveal_type(d2.a)  # noqa
diff --git a/tests/test_pyright.py b/tests/test_pyright.py
 import json
 import os.path
 import shutil
 import subprocess
 import sys

 import pytest

 import attr


 if sys.version_info < (3, 6):
    _found_pyright = False
 else:
    _found_pyright = shutil.which("pyright")


 @attr.s(frozen=True)
 class PyrightDiagnostic(object):
    severity = attr.ib()
    message = attr.ib()


 @pytest.mark.skipif(not _found_pyright, reason="Requires pyright.")
 def test_pyright_baseline():
    """The __dataclass_transform__ decorator allows pyright to determine
    attrs decorated class types.
    """

    test_file = os.path.dirname(__file__) + "/dataclass_transform_example.py"

    pyright = subprocess.run(
        ["pyright", "--outputjson", str(test_file)], capture_output=True
    )
    pyright_result = json.loads(pyright.stdout)

    diagnostics = set(
        PyrightDiagnostic(d["severity"], d["message"])
        for d in pyright_result["generalDiagnostics"]
    )

    # Expected diagnostics as per pyright 1.1.135
    expected_diagnostics = {
        PyrightDiagnostic(
            severity="information",
            message='Type of "Define.__init__" is'
            ' "(self: Define, a: str, b: int) -> None"',
        ),
        PyrightDiagnostic(
            severity="information",
            message='Type of "DefineConverter.__init__" is '
            '"(self: DefineConverter, with_converter: int) -> None"',
        ),
        PyrightDiagnostic(
            severity="information",
            message='Type of "d.a" is "Literal[\'new\']"',
        ),
        PyrightDiagnostic(
            severity="error",
            message='Cannot assign member "a" for type '
            '"FrozenDefine"\n\xa0\xa0"FrozenDefine" is frozen',
        ),
        PyrightDiagnostic(
            severity="information",
            message='Type of "d2.a" is "Literal[\'new\']"',
        ),
    }

    assert diagnostics == expected_diagnostics
diff --git a/tox.ini b/tox.ini
    3.6: py36
    3.7: py37, docs
    3.8: py38, lint, manifest, typing, changelog
    3.9: py39
    3.9: py39, pyright
    3.10: py310
    pypy2: pypy2
    pypy3: pypy3


 [tox]
 envlist = typing,lint,py27,py35,py36,py37,py38,py39,py310,pypy,pypy3,manifest,docs,pypi-description,changelog,coverage-report
 envlist = typing,lint,py27,py35,py36,py37,py38,py39,py310,pypy,pypy3,pyright,manifest,docs,pypi-description,changelog,coverage-report
 isolated_build = True


 commands =
    mypy src/attr/__init__.pyi src/attr/_version_info.pyi src/attr/converters.pyi src/attr/exceptions.pyi src/attr/filters.pyi src/attr/setters.pyi src/attr/validators.pyi
    mypy tests/typing_example.py


 [testenv:pyright]
 # Install and configure node and pyright
 # This *could* be folded into a custom install_command
 # Use nodeenv to configure node in the running tox virtual environment
 # Seeing errors using "nodeenv -p"
 # Use npm install -g to install "globally" into the virtual environment
 basepython = python3.9
 deps = nodeenv
 commands =
    nodeenv --prebuilt --node=lts --force {envdir}
    npm install -g --no-package-lock --no-save pyright@1.1.135
    pytest tests/test_pyright.py -vv
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,4 @@
		``attrs`` has added provisional support for static typing in ``pyright`` version 1.1.135 via the `dataclass_transforms specification <https://github.com/microsoft/pyright/blob/1.1.135/specs/dataclass_transforms.md>`.
		Both the ``pyright`` specification and ``attrs`` implementation may change in future versions of both projects.

		Your constructive feedback is welcome in both `attrs#795 <https://github.com/python-attrs/attrs/issues/795>`_ and `pyright#1782 <https://github.com/microsoft/pyright/discussions/1782>`_.
Original file line number	Diff line number	Diff line change
Expand Up		@@ -46,7 +46,10 @@ An example for that is the package `environ-config <https://github.com/hynek/env

		Another common use case is to overwrite ``attrs``'s defaults.

		Unfortunately, this currently `confuses <https://github.com/python/mypy/issues/5406>`_ mypy's ``attrs`` plugin.
		Mypy
		************

		Unfortunately, decorator wrapping currently `confuses <https://github.com/python/mypy/issues/5406>`_ mypy's ``attrs`` plugin.
		At the moment, the best workaround is to hold your nose, write a fake mypy plugin, and mutate a bunch of global variables::

		from mypy.plugin import Plugin
Expand DownExpand Up		@@ -86,6 +89,34 @@ Then tell mypy about your plugin using your project's ``mypy.ini``:
		Please note that it is currently impossible to let mypy know that you've changed defaults like eq or order.
		You can only use this trick to tell mypy that a class is actually an ``attrs`` class.

		Pyright
		*************

		Generic decorator wrapping is supported in ``pyright`` via the provisional dataclass_transform_ specification.

		For a custom wrapping of the form::

		def custom_define(f):
		return attr.define(f)

		This is implemented via a ``__dataclass_transform__`` type decorator in the custom extension's ``.pyi`` of the form::

		def __dataclass_transform__(
		*,
		eq_default: bool = True,
		order_default: bool = False,
		kw_only_default: bool = False,
		field_descriptors: Tuple[Union[type, Callable[..., Any]], ...] = (()),
		) -> Callable[[_T], _T]: ...

		@__dataclass_transform__(field_descriptors=(attr.attrib, attr.field))
		def custom_define(f): ...

		.. note::

		``dataclass_transform`` is supported provisionally as of ``pyright`` 1.1.135.

		Both the ``pyright`` dataclass_transform_ specification and ``attrs`` implementation may changed in future versions.

		Types
		-----
Expand DownExpand Up		@@ -272,3 +303,7 @@ It has the signature
		{'dt': '2020-05-04T13:37:00'}
		>>> json.dumps(data)
		'{"dt": "2020-05-04T13:37:00"}'

		*****

		.. _dataclass_transform: https://github.com/microsoft/pyright/blob/1.1.135/specs/dataclass_transforms.md
Original file line number	Diff line number	Diff line change
Expand Up		@@ -41,8 +41,11 @@ Also, starting in Python 3.10 (:pep:`526`) all annotations will be string li
		When this happens, ``attrs`` will simply put these string literals into the ``type`` attributes.
		If you need to resolve these to real types, you can call `attr.resolve_types` which will update the attribute in place.

		In practice though, types show their biggest usefulness in combination with tools like mypy_orpytype_ that both have dedicated support for ``attrs`` classes.
		In practice though, types show their biggest usefulness in combination with tools like mypy_, pytype_orpyright_ that have dedicated support for ``attrs`` classes.

		The addition of static types is certainly one of the most exciting features in the Python ecosystem and helps you writing correct and verified self-documenting code.

		If you don't know where to start, Carl Meyer gave a great talk on `Type-checked Python in the Real World <https://www.youtube.com/watch?v=pMgmKJyWKn8>`_ at PyCon US 2018 that will help you to get started in no time.

		mypy
		----
Expand All		@@ -69,12 +72,38 @@ To mypy, this code is equivalent to the one above:
		a_number = attr.ib(default=42) # type: int
		list_of_numbers = attr.ib(factory=list, type=typing.List[int])

		*****

		The addition of static types is certainly one of the most exciting features in the Python ecosystem and helps you writing correct and verified self-documenting code.
		pyright
		-------

		If you don't know where to start, Carl Meyer gave a great talk on `Type-checked Python in the Real World <https://www.youtube.com/watch?v=pMgmKJyWKn8>`_ at PyCon US 2018 that will help you to get started in no time.
		``attrs`` provides support for pyright_ though the dataclass_transform_ specification.
		This provides static type inference for a subset of ``attrs`` equivalent to standard-library ``dataclasses``,
		and requires explicit type annotations using the :ref:`next-gen` or ``@attr.s(auto_attribs=True)`` API.

		Given the following definition, ``pyright`` will generate static type signatures for ``SomeClass`` attribute access, ``__init__``, ``__eq__``, and comparison methods::

		@attr.define
		class SomeClass(object):
		a_number: int = 42
		list_of_numbers: typing.List[int] = attr.field(factory=list)

		.. note::

		``dataclass_transform``-based types are supported provisionally as of ``pyright`` 1.1.135 and ``attrs`` 21.1.
		Both the ``pyright`` dataclass_transform_ specification and ``attrs`` implementation may changed in future versions.

		The ``pyright`` inferred types are a subset of those supported by ``mypy``, including:

		- The generated ``__init__`` signature only includes the attribute type annotations,
		and does not include attribute ``converter`` types.

		- The ``attr.frozen`` decorator is not typed with frozen attributes, which are properly typed via ``attr.define(frozen=True)``.

		Your constructive feedback is welcome in both `attrs#795 <https://github.com/python-attrs/attrs/issues/795>`_ and `pyright#1782 <https://github.com/microsoft/pyright/discussions/1782>`_.

		*****

		.. _mypy: http://mypy-lang.org
		.. _pytype: https://google.github.io/pytype/
		.. _pyright: https://github.com/microsoft/pyright
		.. _dataclass_transform: https://github.com/microsoft/pyright/blob/1.1.135/specs/dataclass_transforms.md
asford marked this conversation as resolved. Show resolvedHide resolved
Original file line number	Diff line number	Diff line change
Expand Up		@@ -86,6 +86,21 @@ else:
		takes_self: bool = ...,
		) -> _T: ...

		# Static type inference support via __dataclass_transform__ implemented as per:
		# https://github.com/microsoft/pyright/blob/1.1.135/specs/dataclass_transforms.md
		# This annotation must be applied to all overloads of "define" and "attrs"
		#
		# NOTE: This is a typing construct and does not exist at runtime. Extensions
		# wrapping attrs decorators should declare a separate __dataclass_transform__
		# signature in the extension module using the specification linked above to
		# provide pyright support.
		def __dataclass_transform__(
Copy link Contributor eurestiApr 27, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. There should probably be an implementation of this somewhere right? Otherwise this won't be useful outside of attrs. Copy link ContributorAuthor asfordApr 28, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. This is a little strange, the decorator is just being used as a marker for`pyright`. The upstream spec specifies that the`__dataclass_transform__` decorator is defined on a per-project basiseither in the a`.py` or`.pyi` source file, essentially as a compatibility layer until this is moved into`typing_extensions`. Copy link Contributor eurestiApr 29, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. Hmm. I'm a little concerned (ok not too much but it definitely feels weird) about having a`def` in the pyi file that doesn't exist in the .py file. It means that someone could try to use this function in their own code but mypy wouldn't warn them that it doesn't really exist. It would fail at runtime. Are we sure we don't want to put an implementation in _funcs.py or something? Copy link ContributorAuthor asfordApr 29, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. 🤔 I've done a little test of this. Under the 1.1.135`pyright` implementation if we: Define a`__dataclass_transform__` decorator in`__init__.pyi` file. Define a`__dataclass_transform__` method in`__funcs.py` and import in`__init__.py`. Then a custom annotation of the form has types inferred properly. importattr@attr.__dataclass_transform__(fields=(attr.field,attr.attrib))defcustom_define(cls):returnattr.define(cls)@custom_defineclassCustom:a:int However, given that this is a very early and provisional specification and implementation in`pyright`, adding a "surprisingly functional" shim in`attrs` introduces a potentially risky coupling. We've a choice between: An immediate and loud runtime failure if you "try to use" the attrs-internal`__dataclass_transform__.pyi` definition, that won't be caught static type checkers. A surprisingly functional form that "works" (a no-op a runtime, currently works at typingtime), but relies on unspecified upstream behavior. Given how bleeding-edge this feature is I have a weakly held preference that we opt for 2 for this release to ensure that folks don't implictly rely on the`import attr.__dataclass_transform__` behavior and instead wait until the spec bakes enough for the`dataclass_transform` to show up in`typing_extensions`. Of course, happy to reconsider. Copy link Contributor eurestiApr 29, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. Since this is only for pyright and doesn't currently get mypy to do the right thing (i.e. it doesn't tell mypy that this is an attrs class creator) perhaps it's best if we leave this only inside the pyi file. I might add a comment on here that says that this method doesn't actually exist at runtime. Copy link ContributorAuthor asfordApr 30, 2021 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. Roger, comment added.
		*,
		eq_default: bool = True,
		order_default: bool = False,
		kw_only_default: bool = False,
		field_descriptors: Tuple[Union[type, Callable[..., Any]], ...] = (()),
		) -> Callable[[_T], _T]: ...

		class Attribute(Generic[_T]):
		name: str
Expand DownExpand Up		@@ -276,6 +291,7 @@ def field(
		on_setattr: Optional[_OnSetAttrArgType] = ...,
		) -> Any: ...
		@overload
		@__dataclass_transform__(order_default=True, field_descriptors=(attrib, field))
		def attrs(
		maybe_cls: _C,
		these: Optional[Dict[str, Any]] = ...,
Expand All		@@ -301,6 +317,7 @@ def attrs(
		field_transformer: Optional[_FieldTransformer] = ...,
		) -> _C: ...
		@overload
		@__dataclass_transform__(order_default=True, field_descriptors=(attrib, field))
		def attrs(
		maybe_cls: None = ...,
		these: Optional[Dict[str, Any]] = ...,
Expand All		@@ -326,6 +343,7 @@ def attrs(
		field_transformer: Optional[_FieldTransformer] = ...,
		) -> Callable[[_C], _C]: ...
		@overload
		@__dataclass_transform__(field_descriptors=(attrib, field))
		def define(
		maybe_cls: _C,
		*,
Expand All		@@ -349,6 +367,7 @@ def define(
		field_transformer: Optional[_FieldTransformer] = ...,
		) -> _C: ...
		@overload
		@__dataclass_transform__(field_descriptors=(attrib, field))
		def define(
		maybe_cls: None = ...,
		*,
Expand Down
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,43 @@
		import attr


		@attr.define()
		class Define:
		a: str
		b: int


		reveal_type(Define.__init__) # noqa


		@attr.define()
		class DefineConverter:
		# mypy plugin adapts the "int" method signature, pyright does not
		with_converter: int = attr.field(converter=int)


		reveal_type(DefineConverter.__init__) # noqa


		# mypy plugin supports attr.frozen, pyright does not
		@attr.frozen()
		class Frozen:
		a: str


		d = Frozen("a")
		d.a = "new"

		reveal_type(d.a) # noqa


		# but pyright supports attr.define(frozen)
		@attr.define(frozen=True)
		class FrozenDefine:
		a: str


		d2 = FrozenDefine("a")
		d2.a = "new"

		reveal_type(d2.a) # noqa
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,69 @@
		import json
		import os.path
		import shutil
		import subprocess
		import sys

		import pytest

		import attr


		if sys.version_info < (3, 6):
		_found_pyright = False
		else:
		_found_pyright = shutil.which("pyright")


		@attr.s(frozen=True)
		class PyrightDiagnostic(object):
		severity = attr.ib()
		message = attr.ib()


		@pytest.mark.skipif(not _found_pyright, reason="Requires pyright.")
		def test_pyright_baseline():
		"""The __dataclass_transform__ decorator allows pyright to determine
		attrs decorated class types.
		"""

		test_file = os.path.dirname(__file__) + "/dataclass_transform_example.py"

		pyright = subprocess.run(
		["pyright", "--outputjson", str(test_file)], capture_output=True
		)
		pyright_result = json.loads(pyright.stdout)

		diagnostics = set(
		PyrightDiagnostic(d["severity"], d["message"])
		for d in pyright_result["generalDiagnostics"]
		)

		# Expected diagnostics as per pyright 1.1.135
		expected_diagnostics = {
		PyrightDiagnostic(
		severity="information",
		message='Type of "Define.__init__" is'
		' "(self: Define, a: str, b: int) -> None"',
		),
		PyrightDiagnostic(
		severity="information",
		message='Type of "DefineConverter.__init__" is '
		'"(self: DefineConverter, with_converter: int) -> None"',
		),
		PyrightDiagnostic(
		severity="information",
		message='Type of "d.a" is "Literal[\'new\']"',
		),
		PyrightDiagnostic(
		severity="error",
		message='Cannot assign member "a" for type '
		'"FrozenDefine"\n\xa0\xa0"FrozenDefine" is frozen',
		),
		PyrightDiagnostic(
		severity="information",
		message='Type of "d2.a" is "Literal[\'new\']"',
		),
		}

		assert diagnostics == expected_diagnostics
Original file line number	Diff line number	Diff line change
Expand Up		@@ -15,14 +15,14 @@ python =
		3.6: py36
		3.7: py37, docs
		3.8: py38, lint, manifest, typing, changelog
		3.9: py39
		3.9: py39, pyright
		3.10: py310
		pypy2: pypy2
		pypy3: pypy3


		[tox]
		envlist = typing,lint,py27,py35,py36,py37,py38,py39,py310,pypy,pypy3,manifest,docs,pypi-description,changelog,coverage-report
		envlist = typing,lint,py27,py35,py36,py37,py38,py39,py310,pypy,pypy3,pyright,manifest,docs,pypi-description,changelog,coverage-report
		isolated_build = True


Expand DownExpand Up		@@ -121,3 +121,17 @@ deps = mypy>=0.800
		commands =
		mypy src/attr/__init__.pyi src/attr/_version_info.pyi src/attr/converters.pyi src/attr/exceptions.pyi src/attr/filters.pyi src/attr/setters.pyi src/attr/validators.pyi
		mypy tests/typing_example.py


		[testenv:pyright]
		# Install and configure node and pyright
		# This could be folded into a custom install_command
		# Use nodeenv to configure node in the running tox virtual environment
		# Seeing errors using "nodeenv -p"
		# Use npm install -g to install "globally" into the virtual environment
		basepython = python3.9
		deps = nodeenv
		commands =
		nodeenv --prebuilt --node=lts --force {envdir}
		npm install -g --no-package-lock --no-save pyright@1.1.135
		pytest tests/test_pyright.py -vv