Refactor providers into package

Author: scottzach1

pif/providers/__init__.py

@@ -0,0 +1,5 @@
+from pif.providers.blank import BlankProvider
+from pif.providers.existing_singleton import ExistingSingleton
+from pif.providers.factory import Factory
+from pif.providers.provider import Provider
+from pif.providers.singleton import Singleton

pif/providers/blank.py

@@ -0,0 +1,23 @@
+#                  _   _                 _     _
+#    ___  ___ ___ | |_| |_ ______ _  ___| |__ / |
+#   / __|/ __/ _ \| __| __|_  / _` |/ __| '_ \| |
+#   \__ \ (_| (_) | |_| |_ / / (_| | (__| | | | |
+#   |___/\___\___/ \__|\__/___\__,_|\___|_| |_|_|
+#
+#        Zac Scott (github.com/scottzach1)
+#
+#  https://github.com/scottzach1/python-injector-framework
+
+from pif import exceptions
+from pif.providers.provider import Provider
+
+
+class BlankProvider(Provider):
+    """
+    A placeholder for a provider.
+    """
+
+    __slots__ = tuple()
+
+    def _evaluate(self) -> None:
+        raise exceptions.BlankProviderException()

pif/providers/existing_singleton.py

@@ -0,0 +1,25 @@
+#                  _   _                 _     _
+#    ___  ___ ___ | |_| |_ ______ _  ___| |__ / |
+#   / __|/ __/ _ \| __| __|_  / _` |/ __| '_ \| |
+#   \__ \ (_| (_) | |_| |_ / / (_| | (__| | | | |
+#   |___/\___\___/ \__|\__/___\__,_|\___|_| |_|_|
+#
+#        Zac Scott (github.com/scottzach1)
+#
+#  https://github.com/scottzach1/python-injector-framework
+
+from pif.providers.provider import Provider
+
+
+class ExistingSingleton[T](Provider):
+    """
+    Provide an existing object instance.
+    """
+
+    __slots__ = ("t",)
+
+    def __init__(self, t: T):
+        self.t = t
+
+    def _evaluate(self) -> T:
+        return self.t

pif/providers/factory.py

@@ -0,0 +1,28 @@
+#                  _   _                 _     _
+#    ___  ___ ___ | |_| |_ ______ _  ___| |__ / |
+#   / __|/ __/ _ \| __| __|_  / _` |/ __| '_ \| |
+#   \__ \ (_| (_) | |_| |_ / / (_| | (__| | | | |
+#   |___/\___\___/ \__|\__/___\__,_|\___|_| |_|_|
+#
+#        Zac Scott (github.com/scottzach1)
+#
+#  https://github.com/scottzach1/python-injector-framework
+
+import functools
+from typing import Callable
+
+from pif.providers.provider import Provider
+
+
+class Factory[T](Provider):
+    """
+    Generate a new instance every call.
+    """
+
+    __slots__ = ("_func", "_depends")
+
+    def __init__(self, func: Callable[[...], T], *args, **kwargs):
+        self._func = functools.partial(func, *args, **kwargs)
+
+    def _evaluate(self) -> T:
+        return self._func()

pif/providers.py renamed to pif/providers/provider.py

@@ -11,10 +11,7 @@
 from __future__ import annotations
 
 import abc
-import functools
-from typing import Callable, Self
-
-from pif import exceptions
+from typing import Self
 
 
 class Provider[T](abc.ABC):
@@ -50,6 +47,8 @@ def override_existing[U](self, value: U) -> Override[Provider[T]]:
         """
         Override the current provider with an existing singleton.
         """
+        from .existing_singleton import ExistingSingleton
+
         return self.override(ExistingSingleton(value))
 
 
@@ -78,62 +77,3 @@ def disable(self) -> None:
 
     def __exit__(self, exc_type, exc_val, exc_tb):
         self.disable()
-
-
-class BlankProvider(Provider):
-    """
-    A placeholder for a provider.
-    """
-
-    __slots__ = tuple()
-
-    def _evaluate(self) -> None:
-        raise exceptions.BlankProviderException()
-
-
-class ExistingSingleton[T](Provider):
-    """
-    Provide an existing object instance.
-    """
-
-    __slots__ = ("t",)
-
-    def __init__(self, t: T):
-        self.t = t
-
-    def _evaluate(self) -> T:
-        return self.t
-
-
-UNSET = object()
-
-
-class Singleton[T](Provider):
-    """
-    Provide a singleton instance.
-    """
-
-    __slots__ = ("_func", "_func", "_result", "_depends")
-
-    def __init__(self, func: Callable[[...], T], *args, **kwargs):
-        self._func = functools.partial(func, *args, **kwargs)
-        self._result = UNSET
-
-    def _evaluate(self) -> T:
-        if self._result is UNSET:
-            self._result = self._func()
-        return self._result
-
-
-class Factory[T](Provider):
-    """
-    Generate a new instance every call.
-    """
-
-    __slots__ = ("_func", "_depends")
-
-    def __init__(self, func: Callable[[...], T], *args, **kwargs):
-        self._func = functools.partial(func, *args, **kwargs)
-
-    def _evaluate(self) -> T:
-        return self._func()

pif/providers/singleton.py

@@ -0,0 +1,33 @@
+#                  _   _                 _     _
+#    ___  ___ ___ | |_| |_ ______ _  ___| |__ / |
+#   / __|/ __/ _ \| __| __|_  / _` |/ __| '_ \| |
+#   \__ \ (_| (_) | |_| |_ / / (_| | (__| | | | |
+#   |___/\___\___/ \__|\__/___\__,_|\___|_| |_|_|
+#
+#        Zac Scott (github.com/scottzach1)
+#
+#  https://github.com/scottzach1/python-injector-framework
+
+import functools
+from typing import Callable
+
+from pif.providers.provider import Provider
+
+UNSET = object()
+
+
+class Singleton[T](Provider):
+    """
+    Provide a singleton instance.
+    """
+
+    __slots__ = ("_func", "_func", "_result", "_depends")
+
+    def __init__(self, func: Callable[[...], T], *args, **kwargs):
+        self._func = functools.partial(func, *args, **kwargs)
+        self._result = UNSET
+
+    def _evaluate(self) -> T:
+        if self._result is UNSET:
+            self._result = self._func()
+        return self._result

pif/wiring.py

@@ -15,7 +15,7 @@
 import types
 from typing import Any, Callable
 
-from pif import providers
+from pif.providers.provider import Provider
 
 
 def patch_args(
@@ -32,7 +32,7 @@ def patch_args(
     :return: injected args and kwargs to pass to func.
     """
     for i, (name, value) in enumerate(signature.parameters.items()):
-        if isinstance(value.default, providers.Provider) and i >= len(args):
+        if isinstance(value.default, Provider) and i >= len(args):
             if value.kind == inspect.Parameter.POSITIONAL_ONLY:
                 args = (
                     *args,
@@ -54,9 +54,12 @@ def inject[T: Callable](func: T) -> T:
     :param func: to decorate.
     :return: the decorated function.
     """
-    signature = inspect.signature(func)
+    try:
+        signature = inspect.signature(func)
+    except ValueError:
+        return func  # We cannot derive signature from provided callable.
 
-    if not any(p for p in signature.parameters.values() if isinstance(p.default, providers.Provider)):
+    if not any(p for p in signature.parameters.values() if isinstance(p.default, Provider)):
         return func
 
     @functools.wraps(func)
@@ -88,7 +91,7 @@ def patch_method[T: Callable | types.FunctionType](func: T) -> T:
     :param func: to patch default values.
     :return: a "patched" version of the method provided.
     """
-    if any(1 for param in inspect.signature(func).parameters.values() if isinstance(param.default, providers.Provider)):
+    if any(1 for param in inspect.signature(func).parameters.values() if isinstance(param.default, Provider)):
         return inject(func)
 
     return func