Add Holder() annotation

openfisca_core/holders/holder.py

@@ -9,15 +9,16 @@
 from openfisca_core.data_storage import InMemoryStorage, OnDiskStorage
 from openfisca_core.indexed_enums import Enum
 from openfisca_core.periods import Period
-from openfisca_core.types import ArrayLike, ArrayType
+from openfisca_core.variables import Variable
+from openfisca_core.types import ArrayLike, ArrayType, Aggregatable
 
 
 class Holder:
     """
     A holder keeps tracks of a variable values after they have been calculated, or set as an input.
     """
 
-    def __init__(self, variable, population):
+    def __init__(self, variable: Variable, population: Aggregatable) -> None:
         self.population = population
         self.variable = variable
         self.simulation = population.simulation

openfisca_core/types/__init__.py

@@ -33,6 +33,7 @@
     )
 
 from .protocols import (  # noqa: F401
+    Aggregatable,
     Buildable,
     Descriptable,
     Personifiable,

openfisca_core/types/callables/formulas.py

@@ -1,8 +1,8 @@
 from typing import Callable
 
-from ..protocols._aggregatable import Aggregatable
 from ..protocols._instantizable import Instantizable
 from ..protocols._timeable import Timeable
+from ..protocols.aggregatable import Aggregatable
 from ..data_types import ArrayType
 
 ParamsType = Callable[[Timeable], Instantizable]

openfisca_core/types/protocols/__init__.py

@@ -21,6 +21,7 @@
 #
 # See: https://www.python.org/dev/peps/pep-0008/#imports
 
+from .aggregatable import Aggregatable  # noqa: F401
 from .buildable import Buildable  # noqa: F401
 from .descriptable import Descriptable  # noqa: F401
 from .personifiable import Personifiable  # noqa: F401

openfisca_core/types/protocols/_aggregatable.py → openfisca_core/types/protocols/aggregatable.py

@@ -1,3 +1,5 @@
+from typing import Any
+
 from typing_extensions import Protocol
 
 
@@ -12,4 +14,7 @@ class Aggregatable(Protocol):
 
     """
 
+    count: int
+    simulation: Any
+
     ...