decorator for time (#59)

* rename origin -> start

* timedelta + testing

* lint

* cast years as int

* closes #54

* rename with maybe prepending decorator

setup.cfg

@@ -34,6 +34,7 @@ install_requires =
 	numpy
 	matplotlib
 	pandas
+	timedelta
 	dataclasses; python_version < "3.7"
 
 # The usage of test_requires is discouraged, see `Dependency Management` docs

simulate.py

@@ -25,7 +25,7 @@ def simulateCoOp(plotList, numYears, pruneYear=None, growthPattern=None, strateg
 
     annualHarvest = []
     harvestYear = []
-    start_year = min([plot.origin.year for plot in plotList])
+    start_year = min([plot.start.year for plot in plotList])
     # start_year = 2020
     for current_year in range(start_year, start_year + numYears + 1):
 

src/cafe/farm.py

@@ -8,10 +8,39 @@
 
 import numpy as np
 import pandas as pd
+import timedelta
 
 _logger = logging.getLogger(__name__)
 
 
+def maybe_time_like(cls):
+    @dataclass
+    class temporal(cls):
+        # start: Optional[datetime.datetime] = datetime.datetime(2020, 1, 1, 0, 0)
+        start: Optional[datetime.datetime] = None
+        end: Optional[datetime.datetime] = None
+
+        @property
+        def year_planted(self):
+            return self.start.year
+
+        def age(self, current_time=datetime.datetime.today()) -> datetime.timedelta:
+            if not self.start:
+                raise ValueError("Start time undefined, age indeterminable.")
+            return current_time - self.start
+
+        def years(self, current_time=datetime.datetime.today()) -> int:
+            return int(timedelta.Timedelta(self.age(current_time)).total.days / 365.25)
+
+        def days(self, current_time=datetime.datetime.today()) -> int:
+            return timedelta.Timedelta(self.age(current_time)).total.days
+
+        def mins(self, current_time=datetime.datetime.today()) -> int:
+            return timedelta.Timedelta(self.age(current_time)).total.minutes
+
+    return temporal
+
+
 @dataclass(frozen=True)
 class Config:
     species: str
@@ -29,23 +58,19 @@ def __eq__(self, other_cls):
         return self.species == other_cls.species and self.unit == other_cls.unit
 
 
+@maybe_time_like
 @dataclass
 class Plot:
     num: int = 1  # number of crops
     area: float = 1.0
     plot_id: int = 0
     species: str = field(default_factory=str)
     unit: str = "cuerdas"
-    origin: datetime = datetime.datetime(2020, 1, 1, 0, 0)
 
     @property  # TODO deprecate / change tests?
     def size(self) -> float:
         return self.area
 
-    @property  # TODO deprecate / change tests?
-    def year_planted(self):
-        return self.origin.year
-
     @staticmethod
     def to_datetime(time) -> datetime.datetime:
         if isinstance(time, Number):  # assumes `time` = year
@@ -63,7 +88,7 @@ def from_series(cls, series):
             species=series.treeType,
             area=series.numCuerdas,
             unit="cuerdas",
-            origin=cls.to_datetime(series.yearPlanted),
+            start=cls.to_datetime(series.yearPlanted),
         )
 
     @classmethod
@@ -105,11 +130,10 @@ def contains(self, species: str = "") -> bool:
         return species in set(p.species for p in self.plot_list)
 
 
+@maybe_time_like
 @dataclass
 class Event:
     name: str
-    start: Optional[datetime.datetime] = None
-    end: Optional[datetime.datetime] = None
     impact: Optional[Union[float, Callable]] = 1.0
     scope: Optional[Union[bool, Dict]] = field(default_factory=dict)
 
@@ -146,18 +170,6 @@ def _check_scope(self, plot: Optional[Plot] = None):
             raise NotImplementedError("Geographic scope not yet implemented.")
         return False
 
-    def age(self, current_time=datetime.datetime.today()) -> datetime.timedelta:
-        return current_time - self.start
-
-    def years(self, current_time=datetime.datetime.today()) -> int:
-        return round(self.age(current_time).days / 365.25)
-
-    def days(self, current_time=datetime.datetime.today()) -> int:
-        return self.age(current_time).days
-
-    def mins(self, current_time=datetime.datetime.today()) -> int:
-        return round(self.age(current_time).seconds / 60)
-
     def eval(self, *args, **kwargs):
         if isinstance(self.impact, Callable):
             return self.impact(*args, **kwargs, **self.__dict__)
@@ -194,7 +206,7 @@ def guate_harvest_function(
     assert mature < retire
 
     def growth(time: Union[datetime.datetime, float], plot: Plot, **kwargs):
-        birth_year = plot.origin.year
+        birth_year = plot.year_planted
         current_year = time if isinstance(time, (float, int)) else time.year
         age = current_year - birth_year
         if age < mature - 1:

tests/test_farm.py

@@ -22,6 +22,11 @@
 __license__ = "mit"
 
 
+@pytest.fixture()
+def start_date():
+    return datetime.datetime(2020, 1, 1)
+
+
 @pytest.fixture()
 def configs():
     return (
@@ -34,7 +39,7 @@ def configs():
 
 @pytest.fixture()
 def farm(start_date):
-    return Farm([Plot(species="a", origin=start_date)])
+    return Farm([Plot(species="a", start=start_date)])
 
 
 @pytest.fixture()
@@ -77,7 +82,7 @@ def f(time, **kwargs):
 @pytest.fixture()
 def growth_function() -> Callable:
     def f(time: Union[datetime.datetime, float], plot: Plot, **kwargs):
-        start = plot.origin.year
+        start = plot.start.year
         year = time if isinstance(time, (float, int)) else time.year
         age = year - start
         if age == 0:
@@ -93,14 +98,9 @@ def f(time: Union[datetime.datetime, float], plot: Plot, **kwargs):
     return f
 
 
-@pytest.fixture()
-def start_date():
-    return datetime.datetime(2020, 1, 1)
-
-
 @pytest.fixture()
 def dummy_event(start_date):
-    return Event("some_event", start_date)
+    return Event("some_event", start=start_date)
 
 
 # CONFIG TESTS
@@ -123,7 +123,7 @@ def test_that_event_impact_works_with_callables(
     start_date, event_impact_function, expected_proportions_for_event
 ):
     # Arrange
-    e = Event("some_event", start_date, impact=event_impact_function)
+    e = Event("some_event", start=start_date, impact=event_impact_function)
     list_of_years, expected_harvest_proportion = expected_proportions_for_event
 
     # Act

tests/test_harvest.py

@@ -13,13 +13,13 @@
 
 
 @pytest.fixture()
-def farm():
-    return Farm([Plot(species="borbon")])
+def start_date():
+    return datetime.datetime(2020, 1, 1)
 
 
 @pytest.fixture()
-def start_date():
-    return datetime.datetime(2020, 1, 1)
+def farm(start_date):
+    return Farm([Plot(species="borbon", start=start_date)])
 
 
 def guate_growth_target(

tests/test_plot.py

@@ -1,6 +1,7 @@
 import pytest
 from cafe.farm import Plot
 import pandas as pd
+import datetime
 
 
 @pytest.fixture
@@ -23,3 +24,33 @@ def test_we_can_instantiate_plot_from_series(series_fixture):
     assert plot.size == info["numCuerdas"]
     assert plot.year_planted == info["yearPlanted"]
     assert plot.plot_id == info["plotID"]
+
+
+def test_that_plots_inherit_time_properties():
+    # Arrange
+    plot = Plot("a", start=datetime.datetime(2000, 1, 1))
+    current_time = datetime.datetime(2020, 1, 1)
+
+    # Act
+    age = plot.age(current_time)
+    years = plot.years(current_time)
+    days = plot.days(current_time)
+    mins = plot.mins(current_time)
+
+    # Assert
+    assert age == datetime.timedelta(days=7305)
+    assert years == 20
+    assert days == 20 * 365.25
+    assert mins == days * 24 * 60
+
+
+def test_that_plots_without_start_time_raises_error():
+    # Arrange
+    plot = Plot("a")
+    current_time = datetime.datetime(2020, 1, 1)
+
+    # Act
+
+    # Assert
+    with pytest.raises(ValueError):
+        plot.age(current_time)