cpython/Lib/test/test_annotationlib.py

"""Tests for the annotations module."""

import textwrap
import annotationlib
import builtins
import collections
import functools
import itertools
import pickle
from string.templatelib import Template
import typing
import unittest
from annotationlib import (
    Format,
    ForwardRef,
    get_annotations,
    annotations_to_string,
    type_repr,
)
from typing import Unpack, get_type_hints, List, Union

from test import support
from test.support import import_helper
from test.test_inspect import inspect_stock_annotations
from test.test_inspect import inspect_stringized_annotations
from test.test_inspect import inspect_stringized_annotations_2
from test.test_inspect import inspect_stringized_annotations_pep695


def times_three(fn):
    @functools.wraps(fn)
    def wrapper(a, b):
        return fn(a * 3, b * 3)

    return wrapper


class MyClass:
    def __repr__(self):
        return "my repr"


class TestFormat(unittest.TestCase):
    def test_enum(self):
        self.assertEqual(Format.VALUE.value, 1)
        self.assertEqual(Format.VALUE, 1)

        self.assertEqual(Format.VALUE_WITH_FAKE_GLOBALS.value, 2)
        self.assertEqual(Format.VALUE_WITH_FAKE_GLOBALS, 2)

        self.assertEqual(Format.FORWARDREF.value, 3)
        self.assertEqual(Format.FORWARDREF, 3)

        self.assertEqual(Format.STRING.value, 4)
        self.assertEqual(Format.STRING, 4)


class TestForwardRefFormat(unittest.TestCase):
    def test_closure(self):
        def inner(arg: x):
            pass

        anno = get_annotations(inner, format=Format.FORWARDREF)
        fwdref = anno["arg"]
        self.assertIsInstance(fwdref, ForwardRef)
        self.assertEqual(fwdref.__forward_arg__, "x")
        with self.assertRaises(NameError):
            fwdref.evaluate()

        x = 1
        self.assertEqual(fwdref.evaluate(), x)

        anno = get_annotations(inner, format=Format.FORWARDREF)
        self.assertEqual(anno["arg"], x)

    def test_function(self):
        def f(x: int, y: doesntexist):
            pass

        anno = get_annotations(f, format=Format.FORWARDREF)
        self.assertIs(anno["x"], int)
        fwdref = anno["y"]
        self.assertIsInstance(fwdref, ForwardRef)
        self.assertEqual(fwdref.__forward_arg__, "doesntexist")
        with self.assertRaises(NameError):
            fwdref.evaluate()
        self.assertEqual(fwdref.evaluate(globals={"doesntexist": 1}), 1)

    def test_nonexistent_attribute(self):
        def f(
            x: some.module,
            y: some[module],
            z: some(module),
            alpha: some | obj,
            beta: +some,
            gamma: some < obj,
        ):
            pass

        anno = get_annotations(f, format=Format.FORWARDREF)
        x_anno = anno["x"]
        self.assertIsInstance(x_anno, ForwardRef)
        self.assertEqual(x_anno, support.EqualToForwardRef("some.module", owner=f))

        y_anno = anno["y"]
        self.assertIsInstance(y_anno, ForwardRef)
        self.assertEqual(y_anno, support.EqualToForwardRef("some[module]", owner=f))

        z_anno = anno["z"]
        self.assertIsInstance(z_anno, ForwardRef)
        self.assertEqual(z_anno, support.EqualToForwardRef("some(module)", owner=f))

        alpha_anno = anno["alpha"]
        self.assertIsInstance(alpha_anno, ForwardRef)
        self.assertEqual(alpha_anno, support.EqualToForwardRef("some | obj", owner=f))

        beta_anno = anno["beta"]
        self.assertIsInstance(beta_anno, ForwardRef)
        self.assertEqual(beta_anno, support.EqualToForwardRef("+some", owner=f))

        gamma_anno = anno["gamma"]
        self.assertIsInstance(gamma_anno, ForwardRef)
        self.assertEqual(gamma_anno, support.EqualToForwardRef("some < obj", owner=f))

    def test_partially_nonexistent_union(self):
        # Test unions with '|' syntax equal unions with typing.Union[] with some forwardrefs
        class UnionForwardrefs:
            pipe: str | undefined
            union: Union[str, undefined]

        annos = get_annotations(UnionForwardrefs, format=Format.FORWARDREF)

        pipe = annos["pipe"]
        self.assertIsInstance(pipe, ForwardRef)
        self.assertEqual(
            pipe.evaluate(globals={"undefined": int}),
            str | int,
        )
        union = annos["union"]
        self.assertIsInstance(union, Union)
        arg1, arg2 = typing.get_args(union)
        self.assertIs(arg1, str)
        self.assertEqual(
            arg2, support.EqualToForwardRef("undefined", is_class=True, owner=UnionForwardrefs)
        )


class TestStringFormat(unittest.TestCase):
    def test_closure(self):
        x = 0

        def inner(arg: x):
            pass

        anno = get_annotations(inner, format=Format.STRING)
        self.assertEqual(anno, {"arg": "x"})

    def test_closure_undefined(self):
        if False:
            x = 0

        def inner(arg: x):
            pass

        anno = get_annotations(inner, format=Format.STRING)
        self.assertEqual(anno, {"arg": "x"})

    def test_function(self):
        def f(x: int, y: doesntexist):
            pass

        anno = get_annotations(f, format=Format.STRING)
        self.assertEqual(anno, {"x": "int", "y": "doesntexist"})

    def test_expressions(self):
        def f(
            add: a + b,
            sub: a - b,
            mul: a * b,
            matmul: a @ b,
            truediv: a / b,
            mod: a % b,
            lshift: a << b,
            rshift: a >> b,
            or_: a | b,
            xor: a ^ b,
            and_: a & b,
            floordiv: a // b,
            pow_: a**b,
            lt: a < b,
            le: a <= b,
            eq: a == b,
            ne: a != b,
            gt: a > b,
            ge: a >= b,
            invert: ~a,
            neg: -a,
            pos: +a,
            getitem: a[b],
            getattr: a.b,
            call: a(b, *c, d=e),  # **kwargs are not supported
            *args: *a,
        ):
            pass

        anno = get_annotations(f, format=Format.STRING)
        self.assertEqual(
            anno,
            {
                "add": "a + b",
                "sub": "a - b",
                "mul": "a * b",
                "matmul": "a @ b",
                "truediv": "a / b",
                "mod": "a % b",
                "lshift": "a << b",
                "rshift": "a >> b",
                "or_": "a | b",
                "xor": "a ^ b",
                "and_": "a & b",
                "floordiv": "a // b",
                "pow_": "a ** b",
                "lt": "a < b",
                "le": "a <= b",
                "eq": "a == b",
                "ne": "a != b",
                "gt": "a > b",
                "ge": "a >= b",
                "invert": "~a",
                "neg": "-a",
                "pos": "+a",
                "getitem": "a[b]",
                "getattr": "a.b",
                "call": "a(b, *c, d=e)",
                "args": "*a",
            },
        )

    def test_reverse_ops(self):
        def f(
            radd: 1 + a,
            rsub: 1 - a,
            rmul: 1 * a,
            rmatmul: 1 @ a,
            rtruediv: 1 / a,
            rmod: 1 % a,
            rlshift: 1 << a,
            rrshift: 1 >> a,
            ror: 1 | a,
            rxor: 1 ^ a,
            rand: 1 & a,
            rfloordiv: 1 // a,
            rpow: 1**a,
        ):
            pass

        anno = get_annotations(f, format=Format.STRING)
        self.assertEqual(
            anno,
            {
                "radd": "1 + a",
                "rsub": "1 - a",
                "rmul": "1 * a",
                "rmatmul": "1 @ a",
                "rtruediv": "1 / a",
                "rmod": "1 % a",
                "rlshift": "1 << a",
                "rrshift": "1 >> a",
                "ror": "1 | a",
                "rxor": "1 ^ a",
                "rand": "1 & a",
                "rfloordiv": "1 // a",
                "rpow": "1 ** a",
            },
        )

    def test_template_str(self):
        def f(
            x: t"{a}",
            y: list[t"{a}"],
            z: t"{a:b} {c!r} {d!s:t}",
            a: t"a{b}c{d}e{f}g",
            b: t"{a:{1}}",
            c: t"{a | b * c}",
        ): pass

        annos = get_annotations(f, format=Format.STRING)
        self.assertEqual(annos, {
            "x": "t'{a}'",
            "y": "list[t'{a}']",
            "z": "t'{a:b} {c!r} {d!s:t}'",
            "a": "t'a{b}c{d}e{f}g'",
            # interpolations in the format spec are eagerly evaluated so we can't recover the source
            "b": "t'{a:1}'",
            "c": "t'{a | b * c}'",
        })

        def g(
            x: t"{a}",
        ): ...

        annos = get_annotations(g, format=Format.FORWARDREF)
        templ = annos["x"]
        # Template and Interpolation don't have __eq__ so we have to compare manually
        self.assertIsInstance(templ, Template)
        self.assertEqual(templ.strings, ("", ""))
        self.assertEqual(len(templ.interpolations), 1)
        interp = templ.interpolations[0]
        self.assertEqual(interp.value, support.EqualToForwardRef("a", owner=g))
        self.assertEqual(interp.expression, "a")
        self.assertIsNone(interp.conversion)
        self.assertEqual(interp.format_spec, "")

    def test_getitem(self):
        def f(x: undef1[str, undef2]):
            pass
        anno = get_annotations(f, format=Format.STRING)
        self.assertEqual(anno, {"x": "undef1[str, undef2]"})

        anno = get_annotations(f, format=Format.FORWARDREF)
        fwdref = anno["x"]
        self.assertIsInstance(fwdref, ForwardRef)
        self.assertEqual(
            fwdref.evaluate(globals={"undef1": dict, "undef2": float}), dict[str, float]
        )

    def test_slice(self):
        def f(x: a[b:c]):
            pass
        anno = get_annotations(f, format=Format.STRING)
        self.assertEqual(anno, {"x": "a[b:c]"})

        def f(x: a[b:c, d:e]):
            pass
        anno = get_annotations(f, format=Format.STRING)
        self.assertEqual(anno, {"x": "a[b:c, d:e]"})

        obj = slice(1, 1, 1)
        def f(x: obj):
            pass
        anno = get_annotations(f, format=Format.STRING)
        self.assertEqual(anno, {"x": "obj"})

    def test_literals(self):
        def f(
            a: 1,
            b: 1.0,
            c: "hello",
            d: b"hello",
            e: True,
            f: None,
            g: ...,
            h: 1j,
        ):
            pass

        anno = get_annotations(f, format=Format.STRING)
        self.assertEqual(
            anno,
            {
                "a": "1",
                "b": "1.0",
                "c": 'hello',
                "d": "b'hello'",
                "e": "True",
                "f": "None",
                "g": "...",
                "h": "1j",
            },
        )

    def test_displays(self):
        # Simple case first
        def f(x: a[[int, str], float]):
            pass
        anno = get_annotations(f, format=Format.STRING)
        self.assertEqual(anno, {"x": "a[[int, str], float]"})

        def g(
            w: a[[int, str], float],
            x: a[{int}, 3],
            y: a[{int: str}, 4],
            z: a[(int, str), 5],
        ):
            pass
        anno = get_annotations(g, format=Format.STRING)
        self.assertEqual(
            anno,
            {
                "w": "a[[int, str], float]",
                "x": "a[{int}, 3]",
                "y": "a[{int: str}, 4]",
                "z": "a[(int, str), 5]",
            },
        )

    def test_nested_expressions(self):
        def f(
            nested: list[Annotated[set[int], "set of ints", 4j]],
            set: {a + b},  # single element because order is not guaranteed
            dict: {a + b: c + d, "key": e + g},
            list: [a, b, c],
            tuple: (a, b, c),
            slice: (a[b:c], a[b:c:d], a[:c], a[b:], a[:], a[::d], a[b::d]),
            extended_slice: a[:, :, c:d],
            unpack1: [*a],
            unpack2: [*a, b, c],
        ):
            pass

        anno = get_annotations(f, format=Format.STRING)
        self.assertEqual(
            anno,
            {
                "nested": "list[Annotated[set[int], 'set of ints', 4j]]",
                "set": "{a + b}",
                "dict": "{a + b: c + d, 'key': e + g}",
                "list": "[a, b, c]",
                "tuple": "(a, b, c)",
                "slice": "(a[b:c], a[b:c:d], a[:c], a[b:], a[:], a[::d], a[b::d])",
                "extended_slice": "a[:, :, c:d]",
                "unpack1": "[*a]",
                "unpack2": "[*a, b, c]",
            },
        )

    def test_unsupported_operations(self):
        format_msg = "Cannot stringify annotation containing string formatting"

        def f(fstring: f"{a}"):
            pass

        with self.assertRaisesRegex(TypeError, format_msg):
            get_annotations(f, format=Format.STRING)

        def f(fstring_format: f"{a:02d}"):
            pass

        with self.assertRaisesRegex(TypeError, format_msg):
            get_annotations(f, format=Format.STRING)

    def test_shenanigans(self):
        # In cases like this we can't reconstruct the source; test that we do something
        # halfway reasonable.
        def f(x: x | (1).__class__, y: (1).__class__):
            pass

        self.assertEqual(
            get_annotations(f, format=Format.STRING),
            {"x": "x | <class 'int'>", "y": "<class 'int'>"},
        )


class TestGetAnnotations(unittest.TestCase):
    def test_builtin_type(self):
        self.assertEqual(get_annotations(int), {})
        self.assertEqual(get_annotations(object), {})

    def test_custom_metaclass(self):
        class Meta(type):
            pass

        class C(metaclass=Meta):
            x: int

        self.assertEqual(get_annotations(C), {"x": int})

    def test_missing_dunder_dict(self):
        class NoDict(type):
            @property
            def __dict__(cls):
                raise AttributeError

            b: str

        class C1(metaclass=NoDict):
            a: int

        self.assertEqual(get_annotations(C1), {"a": int})
        self.assertEqual(
            get_annotations(C1, format=Format.FORWARDREF),
            {"a": int},
        )
        self.assertEqual(
            get_annotations(C1, format=Format.STRING),
            {"a": "int"},
        )
        self.assertEqual(get_annotations(NoDict), {"b": str})
        self.assertEqual(
            get_annotations(NoDict, format=Format.FORWARDREF),
            {"b": str},
        )
        self.assertEqual(
            get_annotations(NoDict, format=Format.STRING),
            {"b": "str"},
        )

    def test_format(self):
        def f1(a: int):
            pass

        def f2(a: undefined):
            pass

        self.assertEqual(
            get_annotations(f1, format=Format.VALUE),
            {"a": int},
        )
        self.assertEqual(get_annotations(f1, format=1), {"a": int})

        fwd = support.EqualToForwardRef("undefined", owner=f2)
        self.assertEqual(
            get_annotations(f2, format=Format.FORWARDREF),
            {"a": fwd},
        )
        self.assertEqual(get_annotations(f2, format=3), {"a": fwd})

        self.assertEqual(
            get_annotations(f1, format=Format.STRING),
            {"a": "int"},
        )
        self.assertEqual(get_annotations(f1, format=4), {"a": "int"})

        with self.assertRaises(ValueError):
            get_annotations(f1, format=42)

        with self.assertRaisesRegex(
            ValueError,
            r"The VALUE_WITH_FAKE_GLOBALS format is for internal use only",
        ):
            get_annotations(f1, format=Format.VALUE_WITH_FAKE_GLOBALS)

        with self.assertRaisesRegex(
            ValueError,
            r"The VALUE_WITH_FAKE_GLOBALS format is for internal use only",
        ):
            get_annotations(f1, format=2)

    def test_custom_object_with_annotations(self):
        class C:
            def __init__(self):
                self.__annotations__ = {"x": int, "y": str}

        self.assertEqual(get_annotations(C()), {"x": int, "y": str})

    def test_custom_format_eval_str(self):
        def foo():
            pass

        with self.assertRaises(ValueError):
            get_annotations(foo, format=Format.FORWARDREF, eval_str=True)
            get_annotations(foo, format=Format.STRING, eval_str=True)

    def test_stock_annotations(self):
        def foo(a: int, b: str):
            pass

        for format in (Format.VALUE, Format.FORWARDREF):
            with self.subTest(format=format):
                self.assertEqual(
                    get_annotations(foo, format=format),
                    {"a": int, "b": str},
                )
        self.assertEqual(
            get_annotations(foo, format=Format.STRING),
            {"a": "int", "b": "str"},
        )

        foo.__annotations__ = {"a": "foo", "b": "str"}
        for format in Format:
            if format == Format.VALUE_WITH_FAKE_GLOBALS:
                continue
            with self.subTest(format=format):
                self.assertEqual(
                    get_annotations(foo, format=format),
                    {"a": "foo", "b": "str"},
                )

        self.assertEqual(
            get_annotations(foo, eval_str=True, locals=locals()),
            {"a": foo, "b": str},
        )
        self.assertEqual(
            get_annotations(foo, eval_str=True, globals=locals()),
            {"a": foo, "b": str},
        )

    def test_stock_annotations_in_module(self):
        isa = inspect_stock_annotations

        for kwargs in [
            {},
            {"eval_str": False},
            {"format": Format.VALUE},
            {"format": Format.FORWARDREF},
            {"format": Format.VALUE, "eval_str": False},
            {"format": Format.FORWARDREF, "eval_str": False},
        ]:
            with self.subTest(**kwargs):
                self.assertEqual(get_annotations(isa, **kwargs), {"a": int, "b": str})
                self.assertEqual(
                    get_annotations(isa.MyClass, **kwargs),
                    {"a": int, "b": str},
                )
                self.assertEqual(
                    get_annotations(isa.function, **kwargs),
                    {"a": int, "b": str, "return": isa.MyClass},
                )
                self.assertEqual(
                    get_annotations(isa.function2, **kwargs),
                    {"a": int, "b": "str", "c": isa.MyClass, "return": isa.MyClass},
                )
                self.assertEqual(
                    get_annotations(isa.function3, **kwargs),
                    {"a": "int", "b": "str", "c": "MyClass"},
                )
                self.assertEqual(
                    get_annotations(annotationlib, **kwargs), {}
                )  # annotations module has no annotations
                self.assertEqual(get_annotations(isa.UnannotatedClass, **kwargs), {})
                self.assertEqual(
                    get_annotations(isa.unannotated_function, **kwargs),
                    {},
                )

        for kwargs in [
            {"eval_str": True},
            {"format": Format.VALUE, "eval_str": True},
        ]:
            with self.subTest(**kwargs):
                self.assertEqual(get_annotations(isa, **kwargs), {"a": int, "b": str})
                self.assertEqual(
                    get_annotations(isa.MyClass, **kwargs),
                    {"a": int, "b": str},
                )
                self.assertEqual(
                    get_annotations(isa.function, **kwargs),
                    {"a": int, "b": str, "return": isa.MyClass},
                )
                self.assertEqual(
                    get_annotations(isa.function2, **kwargs),
                    {"a": int, "b": str, "c": isa.MyClass, "return": isa.MyClass},
                )
                self.assertEqual(
                    get_annotations(isa.function3, **kwargs),
                    {"a": int, "b": str, "c": isa.MyClass},
                )
                self.assertEqual(get_annotations(annotationlib, **kwargs), {})
                self.assertEqual(get_annotations(isa.UnannotatedClass, **kwargs), {})
                self.assertEqual(
                    get_annotations(isa.unannotated_function, **kwargs),
                    {},
                )

        self.assertEqual(
            get_annotations(isa, format=Format.STRING),
            {"a": "int", "b": "str"},
        )
        self.assertEqual(
            get_annotations(isa.MyClass, format=Format.STRING),
            {"a": "int", "b": "str"},
        )
        self.assertEqual(
            get_annotations(isa.function, format=Format.STRING),
            {"a": "int", "b": "str", "return": "MyClass"},
        )
        self.assertEqual(
            get_annotations(isa.function2, format=Format.STRING),
            {"a": "int", "b": "str", "c": "MyClass", "return": "MyClass"},
        )
        self.assertEqual(
            get_annotations(isa.function3, format=Format.STRING),
            {"a": "int", "b": "str", "c": "MyClass"},
        )
        self.assertEqual(
            get_annotations(annotationlib, format=Format.STRING),
            {},
        )
        self.assertEqual(
            get_annotations(isa.UnannotatedClass, format=Format.STRING),
            {},
        )
        self.assertEqual(
            get_annotations(isa.unannotated_function, format=Format.STRING),
            {},
        )

    def test_stock_annotations_on_wrapper(self):
        isa = inspect_stock_annotations

        wrapped = times_three(isa.function)
        self.assertEqual(wrapped(1, "x"), isa.MyClass(3, "xxx"))
        self.assertIsNot(wrapped.__globals__, isa.function.__globals__)
        self.assertEqual(
            get_annotations(wrapped),
            {"a": int, "b": str, "return": isa.MyClass},
        )
        self.assertEqual(
            get_annotations(wrapped, format=Format.FORWARDREF),
            {"a": int, "b": str, "return": isa.MyClass},
        )
        self.assertEqual(
            get_annotations(wrapped, format=Format.STRING),
            {"a": "int", "b": "str", "return": "MyClass"},
        )
        self.assertEqual(
            get_annotations(wrapped, eval_str=True),
            {"a": int, "b": str, "return": isa.MyClass},
        )
        self.assertEqual(
            get_annotations(wrapped, eval_str=False),
            {"a": int, "b": str, "return": isa.MyClass},
        )

    def test_stringized_annotations_in_module(self):
        isa = inspect_stringized_annotations
        for kwargs in [
            {},
            {"eval_str": False},
            {"format": Format.VALUE},
            {"format": Format.FORWARDREF},
            {"format": Format.STRING},
            {"format": Format.VALUE, "eval_str": False},
            {"format": Format.FORWARDREF, "eval_str": False},
            {"format": Format.STRING, "eval_str": False},
        ]:
            with self.subTest(**kwargs):
                self.assertEqual(
                    get_annotations(isa, **kwargs),
                    {"a": "int", "b": "str"},
                )
                self.assertEqual(
                    get_annotations(isa.MyClass, **kwargs),
                    {"a": "int", "b": "str"},
                )
                self.assertEqual(
                    get_annotations(isa.function, **kwargs),
                    {"a": "int", "b": "str", "return": "MyClass"},
                )
                self.assertEqual(
                    get_annotations(isa.function2, **kwargs),
                    {"a": "int", "b": "'str'", "c": "MyClass", "return": "MyClass"},
                )
                self.assertEqual(
                    get_annotations(isa.function3, **kwargs),
                    {"a": "'int'", "b": "'str'", "c": "'MyClass'"},
                )
                self.assertEqual(get_annotations(isa.UnannotatedClass, **kwargs), {})
                self.assertEqual(
                    get_annotations(isa.unannotated_function, **kwargs),
                    {},
                )

        for kwargs in [
            {"eval_str": True},
            {"format": Format.VALUE, "eval_str": True},
        ]:
            with self.subTest(**kwargs):
                self.assertEqual(get_annotations(isa, **kwargs), {"a": int, "b": str})
                self.assertEqual(
                    get_annotations(isa.MyClass, **kwargs),
                    {"a": int, "b": str},
                )
                self.assertEqual(
                    get_annotations(isa.function, **kwargs),
                    {"a": int, "b": str, "return": isa.MyClass},
                )
                self.assertEqual(
                    get_annotations(isa.function2, **kwargs),
                    {"a": int, "b": "str", "c": isa.MyClass, "return": isa.MyClass},
                )
                self.assertEqual(
                    get_annotations(isa.function3, **kwargs),
                    {"a": "int", "b": "str", "c": "MyClass"},
                )
                self.assertEqual(get_annotations(isa.UnannotatedClass, **kwargs), {})
                self.assertEqual(
                    get_annotations(isa.unannotated_function, **kwargs),
                    {},
                )

    def test_stringized_annotations_in_empty_module(self):
        isa2 = inspect_stringized_annotations_2
        self.assertEqual(get_annotations(isa2), {})
        self.assertEqual(get_annotations(isa2, eval_str=True), {})
        self.assertEqual(get_annotations(isa2, eval_str=False), {})

    def test_stringized_annotations_on_wrapper(self):
        isa = inspect_stringized_annotations
        wrapped = times_three(isa.function)
        self.assertEqual(wrapped(1, "x"), isa.MyClass(3, "xxx"))
        self.assertIsNot(wrapped.__globals__, isa.function.__globals__)
        self.assertEqual(
            get_annotations(wrapped),
            {"a": "int", "b": "str", "return": "MyClass"},
        )
        self.assertEqual(
            get_annotations(wrapped, eval_str=True),
            {"a": int, "b": str, "return": isa.MyClass},
        )
        self.assertEqual(
            get_annotations(wrapped, eval_str=False),
            {"a": "int", "b": "str", "return": "MyClass"},
        )

    def test_stringized_annotations_on_class(self):
        isa = inspect_stringized_annotations
        # test that local namespace lookups work
        self.assertEqual(
            get_annotations(isa.MyClassWithLocalAnnotations),
            {"x": "mytype"},
        )
        self.assertEqual(
            get_annotations(isa.MyClassWithLocalAnnotations, eval_str=True),
            {"x": int},
        )

    def test_stringized_annotation_permutations(self):
        def define_class(name, has_future, has_annos, base_text, extra_names=None):
            lines = []
            if has_future:
                lines.append("from __future__ import annotations")
            lines.append(f"class {name}({base_text}):")
            if has_annos:
                lines.append(f"    {name}_attr: int")
            else:
                lines.append("    pass")
            code = "\n".join(lines)
            ns = support.run_code(code, extra_names=extra_names)
            return ns[name]

        def check_annotations(cls, has_future, has_annos):
            if has_annos:
                if has_future:
                    anno = "int"
                else:
                    anno = int
                self.assertEqual(get_annotations(cls), {f"{cls.__name__}_attr": anno})
            else:
                self.assertEqual(get_annotations(cls), {})

        for meta_future, base_future, child_future, meta_has_annos, base_has_annos, child_has_annos in itertools.product(
            (False, True),
            (False, True),
            (False, True),
            (False, True),
            (False, True),
            (False, True),
        ):
            with self.subTest(
                meta_future=meta_future,
                base_future=base_future,
                child_future=child_future,
                meta_has_annos=meta_has_annos,
                base_has_annos=base_has_annos,
                child_has_annos=child_has_annos,
            ):
                meta = define_class(
                    "Meta",
                    has_future=meta_future,
                    has_annos=meta_has_annos,
                    base_text="type",
                )
                base = define_class(
                    "Base",
                    has_future=base_future,
                    has_annos=base_has_annos,
                    base_text="metaclass=Meta",
                    extra_names={"Meta": meta},
                )
                child = define_class(
                    "Child",
                    has_future=child_future,
                    has_annos=child_has_annos,
                    base_text="Base",
                    extra_names={"Base": base},
                )
                check_annotations(meta, meta_future, meta_has_annos)
                check_annotations(base, base_future, base_has_annos)
                check_annotations(child, child_future, child_has_annos)

    def test_modify_annotations(self):
        def f(x: int):
            pass

        self.assertEqual(get_annotations(f), {"x": int})
        self.assertEqual(
            get_annotations(f, format=Format.FORWARDREF),
            {"x": int},
        )

        f.__annotations__["x"] = str
        # The modification is reflected in VALUE (the default)
        self.assertEqual(get_annotations(f), {"x": str})
        # ... and also in FORWARDREF, which tries __annotations__ if available
        self.assertEqual(
            get_annotations(f, format=Format.FORWARDREF),
            {"x": str},
        )
        # ... but not in STRING which always uses __annotate__
        self.assertEqual(
            get_annotations(f, format=Format.STRING),
            {"x": "int"},
        )

    def test_non_dict_annotations(self):
        class WeirdAnnotations:
            @property
            def __annotations__(self):
                return "not a dict"

        wa = WeirdAnnotations()
        for format in Format:
            if format == Format.VALUE_WITH_FAKE_GLOBALS:
                continue
            with (
                self.subTest(format=format),
                self.assertRaisesRegex(
                    ValueError, r".*__annotations__ is neither a dict nor None"
                ),
            ):
                get_annotations(wa, format=format)

    def test_annotations_on_custom_object(self):
        class HasAnnotations:
            @property
            def __annotations__(self):
                return {"x": int}

        ha = HasAnnotations()
        self.assertEqual(get_annotations(ha, format=Format.VALUE), {"x": int})
        self.assertEqual(get_annotations(ha, format=Format.FORWARDREF), {"x": int})

        self.assertEqual(get_annotations(ha, format=Format.STRING), {"x": "int"})

    def test_raising_annotations_on_custom_object(self):
        class HasRaisingAnnotations:
            @property
            def __annotations__(self):
                return {"x": undefined}

        hra = HasRaisingAnnotations()

        with self.assertRaises(NameError):
            get_annotations(hra, format=Format.VALUE)

        with self.assertRaises(NameError):
            get_annotations(hra, format=Format.FORWARDREF)

        undefined = float
        self.assertEqual(get_annotations(hra, format=Format.VALUE), {"x": float})

    def test_forwardref_prefers_annotations(self):
        class HasBoth:
            @property
            def __annotations__(self):
                return {"x": int}

            @property
            def __annotate__(self):
                return lambda format: {"x": str}

        hb = HasBoth()
        self.assertEqual(get_annotations(hb, format=Format.VALUE), {"x": int})
        self.assertEqual(get_annotations(hb, format=Format.FORWARDREF), {"x": int})
        self.assertEqual(get_annotations(hb, format=Format.STRING), {"x": str})

    def test_only_annotate(self):
        def f(x: int):
            pass

        class OnlyAnnotate:
            @property
            def __annotate__(self):
                return f.__annotate__

        oa = OnlyAnnotate()
        self.assertEqual(get_annotations(oa, format=Format.VALUE), {"x": int})
        self.assertEqual(get_annotations(oa, format=Format.FORWARDREF), {"x": int})
        self.assertEqual(
            get_annotations(oa, format=Format.STRING),
            {"x": "int"},
        )

    def test_no_annotations(self):
        class CustomClass:
            pass

        class MyCallable:
            def __call__(self):
                pass

        for format in Format:
            if format == Format.VALUE_WITH_FAKE_GLOBALS:
                continue
            for obj in (None, 1, object(), CustomClass()):
                with self.subTest(format=format, obj=obj):
                    with self.assertRaises(TypeError):
                        get_annotations(obj, format=format)

            # Callables and types with no annotations return an empty dict
            for obj in (int, len, MyCallable()):
                with self.subTest(format=format, obj=obj):
                    self.assertEqual(get_annotations(obj, format=format), {})

    def test_pep695_generic_class_with_future_annotations(self):
        ann_module695 = inspect_stringized_annotations_pep695
        A_annotations = get_annotations(ann_module695.A, eval_str=True)
        A_type_params = ann_module695.A.__type_params__
        self.assertIs(A_annotations["x"], A_type_params[0])
        self.assertEqual(A_annotations["y"].__args__[0], Unpack[A_type_params[1]])
        self.assertIs(A_annotations["z"].__args__[0], A_type_params[2])

    def test_pep695_generic_class_with_future_annotations_and_local_shadowing(self):
        B_annotations = get_annotations(
            inspect_stringized_annotations_pep695.B, eval_str=True
        )
        self.assertEqual(B_annotations, {"x": int, "y": str, "z": bytes})

    def test_pep695_generic_class_with_future_annotations_name_clash_with_global_vars(
        self,
    ):
        ann_module695 = inspect_stringized_annotations_pep695
        C_annotations = get_annotations(ann_module695.C, eval_str=True)
        self.assertEqual(
            set(C_annotations.values()), set(ann_module695.C.__type_params__)
        )

    def test_pep_695_generic_function_with_future_annotations(self):
        ann_module695 = inspect_stringized_annotations_pep695
        generic_func_annotations = get_annotations(
            ann_module695.generic_function, eval_str=True
        )
        func_t_params = ann_module695.generic_function.__type_params__
        self.assertEqual(
            generic_func_annotations.keys(), {"x", "y", "z", "zz", "return"}
        )
        self.assertIs(generic_func_annotations["x"], func_t_params[0])
        self.assertEqual(generic_func_annotations["y"], Unpack[func_t_params[1]])
        self.assertIs(generic_func_annotations["z"].__origin__, func_t_params[2])
        self.assertIs(generic_func_annotations["zz"].__origin__, func_t_params[2])

    def test_pep_695_generic_function_with_future_annotations_name_clash_with_global_vars(
        self,
    ):
        self.assertEqual(
            set(
                get_annotations(
                    inspect_stringized_annotations_pep695.generic_function_2,
                    eval_str=True,
                ).values()
            ),
            set(
                inspect_stringized_annotations_pep695.generic_function_2.__type_params__
            ),
        )

    def test_pep_695_generic_method_with_future_annotations(self):
        ann_module695 = inspect_stringized_annotations_pep695
        generic_method_annotations = get_annotations(
            ann_module695.D.generic_method, eval_str=True
        )
        params = {
            param.__name__: param
            for param in ann_module695.D.generic_method.__type_params__
        }
        self.assertEqual(
            generic_method_annotations,
            {"x": params["Foo"], "y": params["Bar"], "return": None},
        )

    def test_pep_695_generic_method_with_future_annotations_name_clash_with_global_vars(
        self,
    ):
        self.assertEqual(
            set(
                get_annotations(
                    inspect_stringized_annotations_pep695.D.generic_method_2,
                    eval_str=True,
                ).values()
            ),
            set(
                inspect_stringized_annotations_pep695.D.generic_method_2.__type_params__
            ),
        )

    def test_pep_695_generic_method_with_future_annotations_name_clash_with_global_and_local_vars(
        self,
    ):
        self.assertEqual(
            get_annotations(inspect_stringized_annotations_pep695.E, eval_str=True),
            {"x": str},
        )

    def test_pep_695_generics_with_future_annotations_nested_in_function(self):
        results = inspect_stringized_annotations_pep695.nested()

        self.assertEqual(
            set(results.F_annotations.values()), set(results.F.__type_params__)
        )
        self.assertEqual(
            set(results.F_meth_annotations.values()),
            set(results.F.generic_method.__type_params__),
        )
        self.assertNotEqual(
            set(results.F_meth_annotations.values()), set(results.F.__type_params__)
        )
        self.assertEqual(
            set(results.F_meth_annotations.values()).intersection(
                results.F.__type_params__
            ),
            set(),
        )

        self.assertEqual(results.G_annotations, {"x": str})

        self.assertEqual(
            set(results.generic_func_annotations.values()),
            set(results.generic_func.__type_params__),
        )

    def test_partial_evaluation(self):
        def f(
            x: builtins.undef,
            y: list[int],
            z: 1 + int,
            a: builtins.int,
            b: [builtins.undef, builtins.int],
        ):
            pass

        self.assertEqual(
            get_annotations(f, format=Format.FORWARDREF),
            {
                "x": support.EqualToForwardRef("builtins.undef", owner=f),
                "y": list[int],
                "z": support.EqualToForwardRef("1 + int", owner=f),
                "a": int,
                "b": [
                    support.EqualToForwardRef("builtins.undef", owner=f),
                    # We can't resolve this because we have to evaluate the whole annotation
                    support.EqualToForwardRef("builtins.int", owner=f),
                ],
            },
        )

        self.assertEqual(
            get_annotations(f, format=Format.STRING),
            {
                "x": "builtins.undef",
                "y": "list[int]",
                "z": "1 + int",
                "a": "builtins.int",
                "b": "[builtins.undef, builtins.int]",
            },
        )

    def test_partial_evaluation_error(self):
        def f(x: range[1]):
            pass
        with self.assertRaisesRegex(
            TypeError, "type 'range' is not subscriptable"
        ):
            f.__annotations__

        self.assertEqual(
            get_annotations(f, format=Format.FORWARDREF),
            {
                "x": support.EqualToForwardRef("range[1]", owner=f),
            },
        )

    def test_partial_evaluation_cell(self):
        obj = object()

        class RaisesAttributeError:
            attriberr: obj.missing

        anno = get_annotations(RaisesAttributeError, format=Format.FORWARDREF)
        self.assertEqual(
            anno,
            {
                "attriberr": support.EqualToForwardRef(
                    "obj.missing", is_class=True, owner=RaisesAttributeError
                )
            },
        )


class TestCallEvaluateFunction(unittest.TestCase):
    def test_evaluation(self):
        def evaluate(format, exc=NotImplementedError):
            if format > 2:
                raise exc
            return undefined

        with self.assertRaises(NameError):
            annotationlib.call_evaluate_function(evaluate, Format.VALUE)
        self.assertEqual(
            annotationlib.call_evaluate_function(evaluate, Format.FORWARDREF),
            support.EqualToForwardRef("undefined"),
        )
        self.assertEqual(
            annotationlib.call_evaluate_function(evaluate, Format.STRING),
            "undefined",
        )


class MetaclassTests(unittest.TestCase):
    def test_annotated_meta(self):
        class Meta(type):
            a: int

        class X(metaclass=Meta):
            pass

        class Y(metaclass=Meta):
            b: float

        self.assertEqual(get_annotations(Meta), {"a": int})
        self.assertEqual(Meta.__annotate__(Format.VALUE), {"a": int})

        self.assertEqual(get_annotations(X), {})
        self.assertIs(X.__annotate__, None)

        self.assertEqual(get_annotations(Y), {"b": float})
        self.assertEqual(Y.__annotate__(Format.VALUE), {"b": float})

    def test_unannotated_meta(self):
        class Meta(type):
            pass

        class X(metaclass=Meta):
            a: str

        class Y(X):
            pass

        self.assertEqual(get_annotations(Meta), {})
        self.assertIs(Meta.__annotate__, None)

        self.assertEqual(get_annotations(Y), {})
        self.assertIs(Y.__annotate__, None)

        self.assertEqual(get_annotations(X), {"a": str})
        self.assertEqual(X.__annotate__(Format.VALUE), {"a": str})

    def test_ordering(self):
        # Based on a sample by David Ellis
        # https://discuss.python.org/t/pep-749-implementing-pep-649/54974/38

        def make_classes():
            class Meta(type):
                a: int
                expected_annotations = {"a": int}

            class A(type, metaclass=Meta):
                b: float
                expected_annotations = {"b": float}

            class B(metaclass=A):
                c: str
                expected_annotations = {"c": str}

            class C(B):
                expected_annotations = {}

            class D(metaclass=Meta):
                expected_annotations = {}

            return Meta, A, B, C, D

        classes = make_classes()
        class_count = len(classes)
        for order in itertools.permutations(range(class_count), class_count):
            names = ", ".join(classes[i].__name__ for i in order)
            with self.subTest(names=names):
                classes = make_classes()  # Regenerate classes
                for i in order:
                    get_annotations(classes[i])
                for c in classes:
                    with self.subTest(c=c):
                        self.assertEqual(get_annotations(c), c.expected_annotations)
                        annotate_func = getattr(c, "__annotate__", None)
                        if c.expected_annotations:
                            self.assertEqual(
                                annotate_func(Format.VALUE), c.expected_annotations
                            )
                        else:
                            self.assertIs(annotate_func, None)


class TestGetAnnotateFromClassNamespace(unittest.TestCase):
    def test_with_metaclass(self):
        class Meta(type):
            def __new__(mcls, name, bases, ns):
                annotate = annotationlib.get_annotate_from_class_namespace(ns)
                expected = ns["expected_annotate"]
                with self.subTest(name=name):
                    if expected:
                        self.assertIsNotNone(annotate)
                    else:
                        self.assertIsNone(annotate)
                return super().__new__(mcls, name, bases, ns)

        class HasAnnotations(metaclass=Meta):
            expected_annotate = True
            a: int

        class NoAnnotations(metaclass=Meta):
            expected_annotate = False

        class CustomAnnotate(metaclass=Meta):
            expected_annotate = True
            def __annotate__(format):
                return {}

        code = """
            from __future__ import annotations

            class HasFutureAnnotations(metaclass=Meta):
                expected_annotate = False
                a: int
        """
        exec(textwrap.dedent(code), {"Meta": Meta})


class TestTypeRepr(unittest.TestCase):
    def test_type_repr(self):
        class Nested:
            pass

        def nested():
            pass

        self.assertEqual(type_repr(int), "int")
        self.assertEqual(type_repr(MyClass), f"{__name__}.MyClass")
        self.assertEqual(
            type_repr(Nested), f"{__name__}.TestTypeRepr.test_type_repr.<locals>.Nested"
        )
        self.assertEqual(
            type_repr(nested), f"{__name__}.TestTypeRepr.test_type_repr.<locals>.nested"
        )
        self.assertEqual(type_repr(len), "len")
        self.assertEqual(type_repr(type_repr), "annotationlib.type_repr")
        self.assertEqual(type_repr(times_three), f"{__name__}.times_three")
        self.assertEqual(type_repr(...), "...")
        self.assertEqual(type_repr(None), "None")
        self.assertEqual(type_repr(1), "1")
        self.assertEqual(type_repr("1"), "'1'")
        self.assertEqual(type_repr(Format.VALUE), repr(Format.VALUE))
        self.assertEqual(type_repr(MyClass()), "my repr")


class TestAnnotationsToString(unittest.TestCase):
    def test_annotations_to_string(self):
        self.assertEqual(annotations_to_string({}), {})
        self.assertEqual(annotations_to_string({"x": int}), {"x": "int"})
        self.assertEqual(annotations_to_string({"x": "int"}), {"x": "int"})
        self.assertEqual(
            annotations_to_string({"x": int, "y": str}), {"x": "int", "y": "str"}
        )


class A:
    pass


class TestForwardRefClass(unittest.TestCase):
    def test_forwardref_instance_type_error(self):
        fr = ForwardRef("int")
        with self.assertRaises(TypeError):
            isinstance(42, fr)

    def test_forwardref_subclass_type_error(self):
        fr = ForwardRef("int")
        with self.assertRaises(TypeError):
            issubclass(int, fr)

    def test_forwardref_only_str_arg(self):
        with self.assertRaises(TypeError):
            ForwardRef(1)  # only `str` type is allowed

    def test_forward_equality(self):
        fr = ForwardRef("int")
        self.assertEqual(fr, ForwardRef("int"))
        self.assertNotEqual(List["int"], List[int])
        self.assertNotEqual(fr, ForwardRef("int", module=__name__))
        frm = ForwardRef("int", module=__name__)
        self.assertEqual(frm, ForwardRef("int", module=__name__))
        self.assertNotEqual(frm, ForwardRef("int", module="__other_name__"))

    def test_forward_equality_get_type_hints(self):
        c1 = ForwardRef("C")
        c1_gth = ForwardRef("C")
        c2 = ForwardRef("C")
        c2_gth = ForwardRef("C")

        class C:
            pass

        def foo(a: c1_gth, b: c2_gth):
            pass

        self.assertEqual(get_type_hints(foo, globals(), locals()), {"a": C, "b": C})
        self.assertEqual(c1, c2)
        self.assertEqual(c1, c1_gth)
        self.assertEqual(c1_gth, c2_gth)
        self.assertEqual(List[c1], List[c1_gth])
        self.assertNotEqual(List[c1], List[C])
        self.assertNotEqual(List[c1_gth], List[C])
        self.assertEqual(Union[c1, c1_gth], Union[c1])
        self.assertEqual(Union[c1, c1_gth, int], Union[c1, int])

    def test_forward_equality_hash(self):
        c1 = ForwardRef("int")
        c1_gth = ForwardRef("int")
        c2 = ForwardRef("int")
        c2_gth = ForwardRef("int")

        def foo(a: c1_gth, b: c2_gth):
            pass

        get_type_hints(foo, globals(), locals())

        self.assertEqual(hash(c1), hash(c2))
        self.assertEqual(hash(c1_gth), hash(c2_gth))
        self.assertEqual(hash(c1), hash(c1_gth))

        c3 = ForwardRef("int", module=__name__)
        c4 = ForwardRef("int", module="__other_name__")

        self.assertNotEqual(hash(c3), hash(c1))
        self.assertNotEqual(hash(c3), hash(c1_gth))
        self.assertNotEqual(hash(c3), hash(c4))
        self.assertEqual(hash(c3), hash(ForwardRef("int", module=__name__)))

    def test_forward_equality_namespace(self):
        def namespace1():
            a = ForwardRef("A")

            def fun(x: a):
                pass

            get_type_hints(fun, globals(), locals())
            return a

        def namespace2():
            a = ForwardRef("A")

            class A:
                pass

            def fun(x: a):
                pass

            get_type_hints(fun, globals(), locals())
            return a

        self.assertEqual(namespace1(), namespace1())
        self.assertEqual(namespace1(), namespace2())

    def test_forward_repr(self):
        self.assertEqual(repr(List["int"]), "typing.List[ForwardRef('int')]")
        self.assertEqual(
            repr(List[ForwardRef("int", module="mod")]),
            "typing.List[ForwardRef('int', module='mod')]",
        )

    def test_forward_recursion_actually(self):
        def namespace1():
            a = ForwardRef("A")
            A = a

            def fun(x: a):
                pass

            ret = get_type_hints(fun, globals(), locals())
            return a

        def namespace2():
            a = ForwardRef("A")
            A = a

            def fun(x: a):
                pass

            ret = get_type_hints(fun, globals(), locals())
            return a

        r1 = namespace1()
        r2 = namespace2()
        self.assertIsNot(r1, r2)
        self.assertEqual(r1, r2)

    def test_syntax_error(self):

        with self.assertRaises(SyntaxError):
            typing.Generic["/T"]

    def test_delayed_syntax_error(self):

        def foo(a: "Node[T"):
            pass

        with self.assertRaises(SyntaxError):
            get_type_hints(foo)

    def test_syntax_error_empty_string(self):
        for form in [typing.List, typing.Set, typing.Type, typing.Deque]:
            with self.subTest(form=form):
                with self.assertRaises(SyntaxError):
                    form[""]

    def test_or(self):
        X = ForwardRef("X")
        # __or__/__ror__ itself
        self.assertEqual(X | "x", Union[X, "x"])
        self.assertEqual("x" | X, Union["x", X])

    def test_multiple_ways_to_create(self):
        X1 = Union["X"]
        self.assertIsInstance(X1, ForwardRef)
        X2 = ForwardRef("X")
        self.assertIsInstance(X2, ForwardRef)
        self.assertEqual(X1, X2)

    def test_special_attrs(self):
        # Forward refs provide a different introspection API. __name__ and
        # __qualname__ make little sense for forward refs as they can store
        # complex typing expressions.
        fr = ForwardRef("set[Any]")
        self.assertNotHasAttr(fr, "__name__")
        self.assertNotHasAttr(fr, "__qualname__")
        self.assertEqual(fr.__module__, "annotationlib")
        # Forward refs are currently unpicklable once they contain a code object.
        fr.__forward_code__  # fill the cache
        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
            with self.assertRaises(TypeError):
                pickle.dumps(fr, proto)

    def test_evaluate_string_format(self):
        fr = ForwardRef("set[Any]")
        self.assertEqual(fr.evaluate(format=Format.STRING), "set[Any]")

    def test_evaluate_forwardref_format(self):
        fr = ForwardRef("undef")
        evaluated = fr.evaluate(format=Format.FORWARDREF)
        self.assertIs(fr, evaluated)

        fr = ForwardRef("set[undefined]")
        evaluated = fr.evaluate(format=Format.FORWARDREF)
        self.assertEqual(
            evaluated,
            set[support.EqualToForwardRef("undefined")],
        )

        fr = ForwardRef("a + b")
        self.assertEqual(
            fr.evaluate(format=Format.FORWARDREF),
            support.EqualToForwardRef("a + b"),
        )
        self.assertEqual(
            fr.evaluate(format=Format.FORWARDREF, locals={"a": 1, "b": 2}),
            3,
        )

        fr = ForwardRef('"a" + 1')
        self.assertEqual(
            fr.evaluate(format=Format.FORWARDREF),
            support.EqualToForwardRef('"a" + 1'),
        )

    def test_evaluate_with_type_params(self):
        class Gen[T]:
            alias = int

        with self.assertRaises(NameError):
            ForwardRef("T").evaluate()
        with self.assertRaises(NameError):
            ForwardRef("T").evaluate(type_params=())
        with self.assertRaises(NameError):
            ForwardRef("T").evaluate(owner=int)

        (T,) = Gen.__type_params__
        self.assertIs(ForwardRef("T").evaluate(type_params=Gen.__type_params__), T)
        self.assertIs(ForwardRef("T").evaluate(owner=Gen), T)

        with self.assertRaises(NameError):
            ForwardRef("alias").evaluate(type_params=Gen.__type_params__)
        self.assertIs(ForwardRef("alias").evaluate(owner=Gen), int)
        # If you pass custom locals, we don't look at the owner's locals
        with self.assertRaises(NameError):
            ForwardRef("alias").evaluate(owner=Gen, locals={})
        # But if the name exists in the locals, it works
        self.assertIs(
            ForwardRef("alias").evaluate(owner=Gen, locals={"alias": str}), str
        )

    def test_fwdref_with_module(self):
        self.assertIs(ForwardRef("Format", module="annotationlib").evaluate(), Format)
        self.assertIs(
            ForwardRef("Counter", module="collections").evaluate(), collections.Counter
        )
        self.assertEqual(
            ForwardRef("Counter[int]", module="collections").evaluate(),
            collections.Counter[int],
        )

        with self.assertRaises(NameError):
            # If globals are passed explicitly, we don't look at the module dict
            ForwardRef("Format", module="annotationlib").evaluate(globals={})

    def test_fwdref_to_builtin(self):
        self.assertIs(ForwardRef("int").evaluate(), int)
        self.assertIs(ForwardRef("int", module="collections").evaluate(), int)
        self.assertIs(ForwardRef("int", owner=str).evaluate(), int)

        # builtins are still searched with explicit globals
        self.assertIs(ForwardRef("int").evaluate(globals={}), int)

        # explicit values in globals have precedence
        obj = object()
        self.assertIs(ForwardRef("int").evaluate(globals={"int": obj}), obj)

    def test_fwdref_value_is_not_cached(self):
        fr = ForwardRef("hello")
        with self.assertRaises(NameError):
            fr.evaluate()
        self.assertIs(fr.evaluate(globals={"hello": str}), str)
        with self.assertRaises(NameError):
            fr.evaluate()

    def test_fwdref_with_owner(self):
        self.assertEqual(
            ForwardRef("Counter[int]", owner=collections).evaluate(),
            collections.Counter[int],
        )

    def test_name_lookup_without_eval(self):
        # test the codepath where we look up simple names directly in the
        # namespaces without going through eval()
        self.assertIs(ForwardRef("int").evaluate(), int)
        self.assertIs(ForwardRef("int").evaluate(locals={"int": str}), str)
        self.assertIs(
            ForwardRef("int").evaluate(locals={"int": float}, globals={"int": str}),
            float,
        )
        self.assertIs(ForwardRef("int").evaluate(globals={"int": str}), str)
        with support.swap_attr(builtins, "int", dict):
            self.assertIs(ForwardRef("int").evaluate(), dict)

        with self.assertRaises(NameError, msg="name 'doesntexist' is not defined") as exc:
            ForwardRef("doesntexist").evaluate()

        self.assertEqual(exc.exception.name, "doesntexist")

    def test_fwdref_invalid_syntax(self):
        fr = ForwardRef("if")
        with self.assertRaises(SyntaxError):
            fr.evaluate()
        fr = ForwardRef("1+")
        with self.assertRaises(SyntaxError):
            fr.evaluate()


class TestAnnotationLib(unittest.TestCase):
    def test__all__(self):
        support.check__all__(self, annotationlib)

    @support.cpython_only
    def test_lazy_imports(self):
        import_helper.ensure_lazy_imports(
            "annotationlib",
            {
                "typing",
                "warnings",
            },
        )