bench/test_benchmarks.py

"""
Benchmark attrs using CodSpeed.
"""

from __future__ import annotations

import functools
import time

import pytest

import attrs


pytestmark = pytest.mark.benchmark()

ROUNDS = 1_000


def test_create_simple_class():
    """
    Benchmark creating  a simple class without any extras.
    """
    for _ in range(ROUNDS):

        @attrs.define
        class LocalC:
            x: int
            y: str
            z: dict[str, int]


def test_create_frozen_class():
    """
    Benchmark creating a frozen class without any extras.
    """
    for _ in range(ROUNDS):

        @attrs.frozen
        class LocalC:
            x: int
            y: str
            z: dict[str, int]

        LocalC(1, "2", {})


def test_create_simple_class_make_class():
    """
    Benchmark creating a simple class using attrs.make_class().
    """
    for i in range(ROUNDS):
        LocalC = attrs.make_class(
            f"LocalC{i}",
            {
                "x": attrs.field(type=int),
                "y": attrs.field(type=str),
                "z": attrs.field(type=dict[str, int]),
            },
        )

        LocalC(1, "2", {})


@attrs.define
class C:
    x: int = 0
    y: str = "foo"
    z: dict[str, int] = attrs.Factory(dict)


def test_instantiate_no_defaults():
    """
    Benchmark instantiating a class without using any defaults.
    """
    for _ in range(ROUNDS):
        C(1, "2", {})


def test_instantiate_with_defaults():
    """
    Benchmark instantiating a class relying on defaults.
    """
    for _ in range(ROUNDS):
        C()


def test_eq_equal():
    """
    Benchmark comparing two equal instances for equality.
    """
    c1 = C()
    c2 = C()

    for _ in range(ROUNDS):
        c1 == c2


def test_eq_unequal():
    """
    Benchmark comparing two unequal instances for equality.
    """
    c1 = C()
    c2 = C(1, "bar", {"baz": 42})

    for _ in range(ROUNDS):
        c1 == c2


@attrs.frozen
class HashableC:
    x: int = 0
    y: str = "foo"
    z: tuple[str] = ("bar",)


def test_hash():
    """
    Benchmark hashing an instance.
    """
    c = HashableC()

    for _ in range(ROUNDS):
        hash(c)


def test_asdict_complicated():
    """
    Benchmark instances with non-shortcut fields.
    """
    c = C()
    ad = attrs.asdict

    for _ in range(ROUNDS):
        ad(c)


def test_astuple_complicated():
    """
    Benchmark instances with non-shortcut fields.
    """
    c = C()
    at = attrs.astuple

    for _ in range(ROUNDS):
        at(c)


@attrs.define
class AtomicFields:
    a: int = 0
    b: Ellipsis = ...
    c: str = "foo"
    d: tuple[str] = "bar"
    e: complex = 0j


def test_asdict_atomic():
    """
    Benchmark atomic-only instances.
    """
    c = AtomicFields()
    ad = attrs.asdict

    for _ in range(ROUNDS):
        ad(c)


def test_astuple_atomic():
    """
    Benchmark atomic-only instances.
    """
    c = AtomicFields()
    at = attrs.astuple

    for _ in range(ROUNDS):
        at(c)


class TestCachedProperties:
    @attrs.define
    class Slotted:
        x: int = 0

        @functools.cached_property
        def cached(self):
            time.sleep(0.1)
            return 42

    @attrs.define(slots=False)
    class Unslotted:
        x: int = 0

        @functools.cached_property
        def cached(self):
            time.sleep(0.1)
            return 42

    def test_first_access(self):
        """
        Benchmark first access to a cached property (computation + storage).
        """
        for _ in range(ROUNDS):
            c = self.Slotted(42)
            _ = c.cached

    def test_repeated_access(self):
        """
        Benchmark repeated access to a cached property (should use stored
        value).
        """
        c = self.Slotted(42)
        _ = c.cached  # Prime the cache

        for _ in range(ROUNDS):
            _ = c.cached

    def test_create_cached_property_class(self):
        """
        Benchmark creating a class with a cached property
        """
        for _ in range(ROUNDS):

            @attrs.define
            class LocalC:
                x: int
                y: str
                z: dict[str, int]

                @functools.cached_property
                def cached(self):
                    return 42