fix: random seed configuration (litestar-org#321)

Co-authored-by: Jacob Coffee <jacob@z7x.org>

docs/examples/configuration/test_example_1.py

@@ -1,6 +1,5 @@
 from dataclasses import dataclass
 
-from polyfactory import Use
 from polyfactory.factories import DataclassFactory
 
 
@@ -16,7 +15,9 @@ class PersonFactory(DataclassFactory[Person]):
     __model__ = Person
     __random_seed__ = 1
 
-    name = Use(DataclassFactory.__random__.choice, ["John", "Alice", "George"])
+    @classmethod
+    def name(cls) -> str:
+        return cls.__random__.choice(["John", "Alice", "George"])
 
 
 def test_random_seed() -> None:

docs/examples/configuration/test_example_2.py

@@ -1,7 +1,6 @@
 from dataclasses import dataclass
 from random import Random
 
-from polyfactory import Use
 from polyfactory.factories import DataclassFactory
 
 
@@ -17,11 +16,13 @@ class PersonFactory(DataclassFactory[Person]):
     __model__ = Person
     __random__ = Random(10)
 
-    name = Use(DataclassFactory.__random__.choice, ["John", "Alice", "George"])
+    @classmethod
+    def name(cls) -> str:
+        return cls.__random__.choice(["John", "Alice", "George"])
 
 
 def test_setting_random() -> None:
     # the outcome of 'factory.__random__.choice' is deterministic, because Random is configured with a set value.
-    assert PersonFactory.build().name == "Alice"
+    assert PersonFactory.build().name == "George"
     assert PersonFactory.build().name == "John"
     assert PersonFactory.build().name == "Alice"

docs/examples/configuration/test_example_3.py

@@ -26,4 +26,4 @@ def name(cls) -> str:
 
 def test_setting_faker() -> None:
     # the outcome of faker deterministic because we seeded random, and it uses a spanish locale.
-    assert PersonFactory.build().name == "Lucas Barroso Jara"
+    assert PersonFactory.build().name == "Jessica Lane"

polyfactory/factories/base.py

@@ -21,6 +21,7 @@
 )
 from os.path import realpath
 from pathlib import Path
+from random import Random
 from typing import (
     TYPE_CHECKING,
     Any,
@@ -79,8 +80,6 @@
 )
 
 if TYPE_CHECKING:
-    from random import Random
-
     from typing_extensions import TypeGuard
 
     from polyfactory.field_meta import Constraints, FieldMeta
@@ -255,7 +254,8 @@ def __init_subclass__(cls, *args: Any, **kwargs: Any) -> None:
         else:
             BaseFactory._base_factories.append(cls)
 
-        if random_seed := getattr(cls, "__random_seed__", None) is not None:
+        random_seed = getattr(cls, "__random_seed__", None)
+        if random_seed is not None:
             cls.seed_random(random_seed)
 
         if cls.__set_as_default_factory_for_type__:
@@ -401,8 +401,11 @@ def seed_random(cls, seed: int) -> None:
         :returns: 'None'
 
         """
-        cls.__random__.seed(seed, version=3)
-        cls.__faker__.seed_instance(seed)
+        cls.__random__ = Random(seed)
+
+        faker = Faker()
+        faker.seed_instance(seed)
+        cls.__faker__ = faker
 
     @classmethod
     def is_ignored_type(cls, value: Any) -> bool:

pyproject.toml

@@ -115,6 +115,7 @@ include = ["polyfactory", "tests", "examples"]
 omit = ["*/tests/*"]
 
 [tool.pytest.ini_options]
+addopts = "tests docs/examples"
 asyncio_mode = "auto"
 filterwarnings = [
     "ignore:.*pkg_resources.declare_namespace\\('sphinxcontrib'\\).*:DeprecationWarning",

tests/test_random_configuration.py

@@ -0,0 +1,92 @@
+from dataclasses import dataclass
+from random import Random
+from typing import cast
+
+import pytest
+
+from polyfactory.factories.dataclass_factory import DataclassFactory
+
+RANDINT_MAP = {i: Random(i).randint(0, 10) for i in range(3)}
+
+
+@pytest.mark.parametrize("seed", RANDINT_MAP.keys())
+def test_setting_random(seed: int) -> None:
+    @dataclass
+    class Foo:
+        foo: int
+
+    class FooFactory(DataclassFactory[Foo]):
+        __model__ = Foo
+        __random__ = Random(seed)
+
+        @classmethod
+        def foo(cls) -> int:
+            return cls.__random__.randint(0, 10)
+
+    assert FooFactory.build().foo == RANDINT_MAP[seed]
+
+
+@pytest.mark.parametrize("seed", RANDINT_MAP.keys())
+def test_setting_random_seed_on_random(seed: int) -> None:
+    @dataclass
+    class Foo:
+        foo: int
+
+    class FooFactory(DataclassFactory[Foo]):
+        __model__ = Foo
+        __random_seed__ = seed
+
+        @classmethod
+        def foo(cls) -> int:
+            return cls.__random__.randint(0, 10)
+
+    assert FooFactory.build().foo == RANDINT_MAP[seed]
+
+
+@pytest.mark.parametrize("seed", RANDINT_MAP.keys())
+def test_setting_random_seed_on_faker(seed: int) -> None:
+    @dataclass
+    class Foo:
+        foo: int
+
+    class FooFactory(DataclassFactory[Foo]):
+        __model__ = Foo
+        __random_seed__ = seed
+
+        @classmethod
+        def foo(cls) -> int:
+            return cast(int, cls.__faker__.random_digit())
+
+    assert FooFactory.build().foo == RANDINT_MAP[seed]
+
+
+def test_setting_random_seed_on_multiple_factories() -> None:
+    foo_seed = 0
+    bar_seed = 1
+
+    @dataclass
+    class Foo:
+        foo: int
+
+    @dataclass
+    class Bar:
+        bar: int
+
+    class FooFactory(DataclassFactory[Foo]):
+        __model__ = Foo
+        __random_seed__ = foo_seed
+
+        @classmethod
+        def foo(cls) -> int:
+            return cls.__random__.randint(0, 10)
+
+    class BarFactory(DataclassFactory[Bar]):
+        __model__ = Bar
+        __random_seed__ = bar_seed
+
+        @classmethod
+        def bar(cls) -> int:
+            return cls.__random__.randint(0, 10)
+
+    assert FooFactory.build().foo == RANDINT_MAP[foo_seed]
+    assert BarFactory.build().bar == RANDINT_MAP[bar_seed]