ch11-24: clean up by @eumiro & sync with Atlas

13-protocol-abc/typing/randompick.py

@@ -0,0 +1,5 @@
+from typing import Protocol, runtime_checkable, Any
+
+@runtime_checkable
+class RandomPicker(Protocol):
+    def pick(self) -> Any: ...

13-protocol-abc/typing/randompick_test.py

@@ -0,0 +1,25 @@
+import random
+from typing import Any, Iterable, TYPE_CHECKING
+
+from randompick import RandomPicker  # <1>
+
+class SimplePicker():  # <2>
+    def __init__(self, items: Iterable) -> None:
+        self._items = list(items)
+        random.shuffle(self._items)
+
+    def pick(self) -> Any:  # <3>
+        return self._items.pop()
+
+def test_isinstance() -> None:  # <4>
+    popper = SimplePicker([1])
+    assert isinstance(popper, RandomPicker)
+
+def test_item_type() -> None:  # <5>
+    items = [1, 2]
+    popper = SimplePicker(items)
+    item = popper.pick()
+    assert item in items
+    if TYPE_CHECKING:
+        reveal_type(item)  # <6>
+    assert isinstance(item, int)

13-protocol-abc/typing/randompickload.py

@@ -0,0 +1,6 @@
+from typing import Protocol, runtime_checkable, Any, Iterable
+from randompick import RandomPicker
+
+@runtime_checkable  # <1>
+class LoadableRandomPicker(RandomPicker, Protocol):  # <2>
+    def load(self, Iterable) -> None: ...  # <3>

13-protocol-abc/typing/randompickload_test.py

@@ -0,0 +1,32 @@
+import random
+from typing import Any, Iterable, TYPE_CHECKING
+
+from randompickload import LoadableRandomPicker
+
+class SimplePicker():
+    def __init__(self, items: Iterable) -> None:
+        self._items = list(items)
+        random.shuffle(self._items)
+
+    def pick(self) -> Any:
+        return self._items.pop()
+
+class LoadablePicker():  # <1>
+    def __init__(self, items: Iterable) -> None:
+        self.load(items)
+
+    def pick(self) -> Any:  # <2>
+        return self._items.pop()
+
+    def load(self, items: Iterable) -> Any:  # <3>
+        self._items = list(items)
+        random.shuffle(self._items)
+
+def test_isinstance() -> None:  # <4>
+    popper = LoadablePicker([1])
+    assert isinstance(popper, LoadableRandomPicker)
+
+def test_isinstance_not() -> None:  # <5>
+    popper = SimplePicker([1])
+    assert not isinstance(popper, LoadableRandomPicker)
+

13-protocol-abc/typing/vector2d_v4.py

@@ -0,0 +1,172 @@
+"""
+A two-dimensional vector class
+
+    >>> v1 = Vector2d(3, 4)
+    >>> print(v1.x, v1.y)
+    3.0 4.0
+    >>> x, y = v1
+    >>> x, y
+    (3.0, 4.0)
+    >>> v1
+    Vector2d(3.0, 4.0)
+    >>> v1_clone = eval(repr(v1))
+    >>> v1 == v1_clone
+    True
+    >>> print(v1)
+    (3.0, 4.0)
+    >>> octets = bytes(v1)
+    >>> octets
+    b'd\\x00\\x00\\x00\\x00\\x00\\x00\\x08@\\x00\\x00\\x00\\x00\\x00\\x00\\x10@'
+    >>> abs(v1)
+    5.0
+    >>> bool(v1), bool(Vector2d(0, 0))
+    (True, False)
+
+
+Test of ``.frombytes()`` class method:
+
+    >>> v1_clone = Vector2d.frombytes(bytes(v1))
+    >>> v1_clone
+    Vector2d(3.0, 4.0)
+    >>> v1 == v1_clone
+    True
+
+
+Tests of ``format()`` with Cartesian coordinates:
+
+    >>> format(v1)
+    '(3.0, 4.0)'
+    >>> format(v1, '.2f')
+    '(3.00, 4.00)'
+    >>> format(v1, '.3e')
+    '(3.000e+00, 4.000e+00)'
+
+
+Tests of the ``angle`` method::
+
+    >>> Vector2d(0, 0).angle()
+    0.0
+    >>> Vector2d(1, 0).angle()
+    0.0
+    >>> epsilon = 10**-8
+    >>> abs(Vector2d(0, 1).angle() - math.pi/2) < epsilon
+    True
+    >>> abs(Vector2d(1, 1).angle() - math.pi/4) < epsilon
+    True
+
+
+Tests of ``format()`` with polar coordinates:
+
+    >>> format(Vector2d(1, 1), 'p')  # doctest:+ELLIPSIS
+    '<1.414213..., 0.785398...>'
+    >>> format(Vector2d(1, 1), '.3ep')
+    '<1.414e+00, 7.854e-01>'
+    >>> format(Vector2d(1, 1), '0.5fp')
+    '<1.41421, 0.78540>'
+
+
+Tests of ``x`` and ``y`` read-only properties:
+
+    >>> v1.x, v1.y
+    (3.0, 4.0)
+    >>> v1.x = 123
+    Traceback (most recent call last):
+      ...
+    AttributeError: can't set attribute
+
+
+Tests of hashing:
+
+    >>> v1 = Vector2d(3, 4)
+    >>> v2 = Vector2d(3.1, 4.2)
+    >>> hash(v1), hash(v2)
+    (7, 384307168202284039)
+    >>> len(set([v1, v2]))
+    2
+
+Converting to/from a ``complex``:
+# tag::VECTOR2D_V4_DEMO[]
+    >>> from typing import SupportsComplex
+    >>> v3 = Vector2d(1.5, 2.5)
+    >>> isinstance(v3, SupportsComplex)  # <1>
+    True
+    >>> complex(v3)  # <2>
+    (1.5+2.5j)
+    >>> Vector2d.fromcomplex(4+5j)  # <3>
+    Vector2d(4.0, 5.0)
+
+# end::VECTOR2D_V4_DEMO[]
+"""
+
+from array import array
+import math
+
+class Vector2d:
+    typecode = 'd'
+
+    def __init__(self, x, y):
+        self.__x = float(x)
+        self.__y = float(y)
+
+    @property
+    def x(self):
+        return self.__x
+
+    @property
+    def y(self):
+        return self.__y
+
+    def __iter__(self):
+        return (i for i in (self.x, self.y))
+
+    def __repr__(self):
+        class_name = type(self).__name__
+        return '{}({!r}, {!r})'.format(class_name, *self)
+
+    def __str__(self):
+        return str(tuple(self))
+
+    def __bytes__(self):
+        return (bytes([ord(self.typecode)]) +
+                bytes(array(self.typecode, self)))
+
+    def __eq__(self, other):
+        return tuple(self) == tuple(other)
+
+    def __hash__(self):
+        return hash(self.x) ^ hash(self.y)
+
+    def __abs__(self):
+        return math.hypot(self.x, self.y)
+
+    def __bool__(self):
+        return bool(abs(self))
+
+    def angle(self):
+        return math.atan2(self.y, self.x)
+
+    def __format__(self, fmt_spec=''):
+        if fmt_spec.endswith('p'):
+            fmt_spec = fmt_spec[:-1]
+            coords = (abs(self), self.angle())
+            outer_fmt = '<{}, {}>'
+        else:
+            coords = self
+            outer_fmt = '({}, {})'
+        components = (format(c, fmt_spec) for c in coords)
+        return outer_fmt.format(*components)
+
+    @classmethod
+    def frombytes(cls, octets):
+        typecode = chr(octets[0])
+        memv = memoryview(octets[1:]).cast(typecode)
+        return cls(*memv)
+
+# tag::VECTOR2D_V4_COMPLEX[]
+    def __complex__(self):
+        return complex(self.x, self.y)
+
+    @classmethod
+    def fromcomplex(cls, datum):
+        return Vector2d(datum.real, datum.imag)  # <1>
+# end::VECTOR2D_V4_COMPLEX[]

13-protocol-abc/typing/vector2d_v4_test.py

@@ -0,0 +1,56 @@
+from typing import SupportsComplex, SupportsAbs, Tuple
+from typing import TYPE_CHECKING
+import math
+import pytest
+
+from vector2d_v4 import Vector2d
+
+def test_SupportsComplex_subclass() -> None:
+    assert issubclass(Vector2d, SupportsComplex)
+
+def test_SupportsComplex_isinstance() -> None:
+    v = Vector2d(3, 4)
+    assert isinstance(v, SupportsComplex)
+    c = complex(v)
+    assert c == 3 + 4j
+
+def test_SupportsAbs_subclass() -> None:
+    assert issubclass(Vector2d, SupportsAbs)
+
+def test_SupportsAbs_isinstance() -> None:
+    v = Vector2d(3, 4)
+    assert isinstance(v, SupportsAbs)
+    r = abs(v)
+    assert r == 5.0
+    if TYPE_CHECKING:
+        reveal_type(r)  # Revealed type is 'Any'
+
+def magnitude(v: SupportsAbs) -> float:
+    return abs(v)
+
+def test_SupportsAbs_Vector2d_argument() -> None:
+    assert magnitude(Vector2d(3, 4)) == 5.0
+
+def test_SupportsAbs_object_argument() -> None:
+    with pytest.raises(TypeError):
+        magnitude(object())
+        # mypy error:
+        # Argument 1 to "magnitude" has incompatible type "object"; expected "SupportsAbs[Any]"
+
+def polar(datum: SupportsComplex) -> Tuple[float, float]:
+    c = complex(datum)
+    return abs(c), math.atan2(c.imag, c.real)
+
+def test_SupportsComplex_Vector2d_argument() -> None:
+    assert polar(Vector2d(2, 0)) == (2, 0)
+    expected = (2, math.pi / 2)
+    result = polar(Vector2d(0, 2))
+    assert math.isclose(result[0], expected[0])
+    assert math.isclose(result[1], expected[1])
+
+def test_SupportsComplex_complex_argument() -> None:
+    assert polar(complex(2, 0)) == (2, 0)
+    expected = (2, math.pi / 2)
+    result = polar(complex(0, 2))
+    assert math.isclose(result[0], expected[0])
+    assert math.isclose(result[1], expected[1])

13-protocol-abc/typing/vector2d_v5.py

@@ -0,0 +1,174 @@
+from __future__ import annotations
+
+"""
+A two-dimensional vector class
+
+    >>> v1 = Vector2d(3, 4)
+    >>> print(v1.x, v1.y)
+    3.0 4.0
+    >>> x, y = v1
+    >>> x, y
+    (3.0, 4.0)
+    >>> v1
+    Vector2d(3.0, 4.0)
+    >>> v1_clone = eval(repr(v1))
+    >>> v1 == v1_clone
+    True
+    >>> print(v1)
+    (3.0, 4.0)
+    >>> octets = bytes(v1)
+    >>> octets
+    b'd\\x00\\x00\\x00\\x00\\x00\\x00\\x08@\\x00\\x00\\x00\\x00\\x00\\x00\\x10@'
+    >>> abs(v1)
+    5.0
+    >>> bool(v1), bool(Vector2d(0, 0))
+    (True, False)
+
+
+Test of ``.frombytes()`` class method:
+
+    >>> v1_clone = Vector2d.frombytes(bytes(v1))
+    >>> v1_clone
+    Vector2d(3.0, 4.0)
+    >>> v1 == v1_clone
+    True
+
+
+Tests of ``format()`` with Cartesian coordinates:
+
+    >>> format(v1)
+    '(3.0, 4.0)'
+    >>> format(v1, '.2f')
+    '(3.00, 4.00)'
+    >>> format(v1, '.3e')
+    '(3.000e+00, 4.000e+00)'
+
+
+Tests of the ``angle`` method::
+
+    >>> Vector2d(0, 0).angle()
+    0.0
+    >>> Vector2d(1, 0).angle()
+    0.0
+    >>> epsilon = 10**-8
+    >>> abs(Vector2d(0, 1).angle() - math.pi/2) < epsilon
+    True
+    >>> abs(Vector2d(1, 1).angle() - math.pi/4) < epsilon
+    True
+
+
+Tests of ``format()`` with polar coordinates:
+
+    >>> format(Vector2d(1, 1), 'p')  # doctest:+ELLIPSIS
+    '<1.414213..., 0.785398...>'
+    >>> format(Vector2d(1, 1), '.3ep')
+    '<1.414e+00, 7.854e-01>'
+    >>> format(Vector2d(1, 1), '0.5fp')
+    '<1.41421, 0.78540>'
+
+
+Tests of ``x`` and ``y`` read-only properties:
+
+    >>> v1.x, v1.y
+    (3.0, 4.0)
+    >>> v1.x = 123
+    Traceback (most recent call last):
+      ...
+    AttributeError: can't set attribute
+
+
+Tests of hashing:
+
+    >>> v1 = Vector2d(3, 4)
+    >>> v2 = Vector2d(3.1, 4.2)
+    >>> hash(v1), hash(v2)
+    (7, 384307168202284039)
+    >>> len(set([v1, v2]))
+    2
+
+Converting to/from a ``complex``:
+
+    >>> from typing import SupportsComplex
+    >>> v3 = Vector2d(1.5, 2.5)
+    >>> isinstance(v3, SupportsComplex)  # <1>
+    True
+    >>> complex(v3)  # <2>
+    (1.5+2.5j)
+    >>> Vector2d.fromcomplex(4+5j)  # <3>
+    Vector2d(4.0, 5.0)
+"""
+
+from array import array
+import math
+from typing import SupportsComplex, Iterator
+
+class Vector2d:
+    typecode = 'd'
+
+    def __init__(self, x, y) -> None:
+        self.__x = float(x)
+        self.__y = float(y)
+
+    @property
+    def x(self) -> float:
+        return self.__x
+
+    @property
+    def y(self) -> float:
+        return self.__y
+
+    def __iter__(self) -> Iterator[float]:
+        return (i for i in (self.x, self.y))
+
+    def __repr__(self) -> str:
+        class_name = type(self).__name__
+        return '{}({!r}, {!r})'.format(class_name, *self)
+
+    def __str__(self) -> str:
+        return str(tuple(self))
+
+    def __bytes__(self) -> bytes:
+        return (bytes([ord(self.typecode)]) +
+                bytes(array(self.typecode, self)))
+
+    def __eq__(self, other) -> bool:
+        return tuple(self) == tuple(other)
+
+    def __hash__(self) -> int:
+        return hash(self.x) ^ hash(self.y)
+
+    def __bool__(self) -> bool:
+        return bool(abs(self))
+
+    def angle(self) -> float:
+        return math.atan2(self.y, self.x)
+
+    def __format__(self, fmt_spec='') -> str:
+        if fmt_spec.endswith('p'):
+            fmt_spec = fmt_spec[:-1]
+            coords = (abs(self), self.angle())
+            outer_fmt = '<{}, {}>'
+        else:
+            coords = self
+            outer_fmt = '({}, {})'
+        components = (format(c, fmt_spec) for c in coords)
+        return outer_fmt.format(*components)
+
+    @classmethod
+    def frombytes(cls, octets) -> Vector2d:
+        typecode = chr(octets[0])
+        memv = memoryview(octets[1:]).cast(typecode)
+        return cls(*memv)
+
+# tag::VECTOR2D_V5_COMPLEX[]
+    def __abs__(self) -> float:  # <1>
+        return math.hypot(self.x, self.y)
+
+    def __complex__(self) -> complex:  # <2>
+        return complex(self.x, self.y)
+
+    @classmethod
+    def fromcomplex(cls, datum: SupportsComplex) -> Vector2d:  # <3>
+        c = complex(datum)  # <4>
+        return Vector2d(c.real, c.imag)
+# end::VECTOR2D_V5_COMPLEX[]

13-protocol-abc/typing/vector2d_v5_test.py

@@ -0,0 +1,35 @@
+from vector2d_v5 import Vector2d
+from typing import SupportsComplex, SupportsAbs, TYPE_CHECKING
+
+import pytest
+
+
+def test_SupportsComplex_subclass() -> None:
+    assert issubclass(Vector2d, SupportsComplex)
+
+def test_SupportsComplex_isinstance() -> None:
+    v = Vector2d(3, 4)
+    assert isinstance(v, SupportsComplex)
+    c = complex(v)
+    assert c == 3 + 4j
+
+def test_SupportsAbs_subclass() -> None:
+    assert issubclass(Vector2d, SupportsAbs)
+
+def test_SupportsAbs_isinstance() -> None:
+    v = Vector2d(3, 4)
+    assert isinstance(v, SupportsAbs)
+    r = abs(v)
+    assert r == 5.0
+    if TYPE_CHECKING:
+        reveal_type(r)  # Revealed type is 'builtins.float*'
+
+def magnitude(v: SupportsAbs) -> float:
+    return abs(v)
+
+def test_SupportsAbs_Vector2d_argument() -> None:
+    assert 5.0 == magnitude(Vector2d(3, 4))
+
+def test_SupportsAbs_object_argument() -> None:
+    with pytest.raises(TypeError):
+        assert 5.0 == magnitude(object())