implement Delegate portions of pandas-dev#24024 (pandas-dev#24463)

Author: jbrockmendel

pandas/core/indexes/accessors.py

@@ -11,9 +11,11 @@
 
 from pandas.core.accessor import PandasDelegate, delegate_names
 from pandas.core.algorithms import take_1d
+from pandas.core.arrays import (
+    DatetimeArrayMixin as DatetimeArray, PeriodArray,
+    TimedeltaArrayMixin as TimedeltaArray)
 from pandas.core.base import NoNewAttributesMixin, PandasObject
 from pandas.core.indexes.datetimes import DatetimeIndex
-from pandas.core.indexes.period import PeriodArray
 from pandas.core.indexes.timedeltas import TimedeltaIndex
 
 
@@ -106,11 +108,11 @@ def _delegate_method(self, name, *args, **kwargs):
         return result
 
 
-@delegate_names(delegate=DatetimeIndex,
-                accessors=DatetimeIndex._datetimelike_ops,
+@delegate_names(delegate=DatetimeArray,
+                accessors=DatetimeArray._datetimelike_ops,
                 typ="property")
-@delegate_names(delegate=DatetimeIndex,
-                accessors=DatetimeIndex._datetimelike_methods,
+@delegate_names(delegate=DatetimeArray,
+                accessors=DatetimeArray._datetimelike_methods,
                 typ="method")
 class DatetimeProperties(Properties):
     """
@@ -177,11 +179,11 @@ def freq(self):
         return self._get_values().inferred_freq
 
 
-@delegate_names(delegate=TimedeltaIndex,
-                accessors=TimedeltaIndex._datetimelike_ops,
+@delegate_names(delegate=TimedeltaArray,
+                accessors=TimedeltaArray._datetimelike_ops,
                 typ="property")
-@delegate_names(delegate=TimedeltaIndex,
-                accessors=TimedeltaIndex._datetimelike_methods,
+@delegate_names(delegate=TimedeltaArray,
+                accessors=TimedeltaArray._datetimelike_methods,
                 typ="method")
 class TimedeltaProperties(Properties):
     """

pandas/core/indexes/datetimelike.py

@@ -594,63 +594,6 @@ def wrap_arithmetic_op(self, other, result):
     return result
 
 
-def wrap_array_method(method, pin_name=False):
-    """
-    Wrap a DatetimeArray/TimedeltaArray/PeriodArray method so that the
-    returned object is an Index subclass instead of ndarray or ExtensionArray
-    subclass.
-
-    Parameters
-    ----------
-    method : method of Datetime/Timedelta/Period Array class
-    pin_name : bool
-        Whether to set name=self.name on the output Index
-
-    Returns
-    -------
-    method
-    """
-    def index_method(self, *args, **kwargs):
-        result = method(self._eadata, *args, **kwargs)
-
-        # Index.__new__ will choose the appropriate subclass to return
-        result = Index(result)
-        if pin_name:
-            result.name = self.name
-        return result
-
-    index_method.__name__ = method.__name__
-    index_method.__doc__ = method.__doc__
-    return index_method
-
-
-def wrap_field_accessor(prop):
-    """
-    Wrap a DatetimeArray/TimedeltaArray/PeriodArray array-returning property
-    to return an Index subclass instead of ndarray or ExtensionArray subclass.
-
-    Parameters
-    ----------
-    prop : property
-
-    Returns
-    -------
-    new_prop : property
-    """
-    fget = prop.fget
-
-    def f(self):
-        result = fget(self._eadata)
-        if is_bool_dtype(result):
-            # return numpy array b/c there is no BoolIndex
-            return result
-        return Index(result, name=self.name)
-
-    f.__name__ = fget.__name__
-    f.__doc__ = fget.__doc__
-    return property(f)
-
-
 def maybe_unwrap_index(obj):
     """
     If operating against another Index object, we need to unwrap the underlying
@@ -703,16 +646,16 @@ def _delegate_class(self):
         raise AbstractMethodError
 
     def _delegate_property_get(self, name, *args, **kwargs):
-        result = getattr(self._data, name)
+        result = getattr(self._eadata, name)
         if name not in self._raw_properties:
             result = Index(result, name=self.name)
         return result
 
     def _delegate_property_set(self, name, value, *args, **kwargs):
-        setattr(self._data, name, value)
+        setattr(self._eadata, name, value)
 
     def _delegate_method(self, name, *args, **kwargs):
-        result = operator.methodcaller(name, *args, **kwargs)(self._data)
+        result = operator.methodcaller(name, *args, **kwargs)(self._eadata)
         if name not in self._raw_methods:
             result = Index(result, name=self.name)
         return result

pandas/core/indexes/datetimes.py

@@ -20,13 +20,14 @@
 import pandas.core.dtypes.concat as _concat
 from pandas.core.dtypes.missing import isna
 
+from pandas.core.accessor import delegate_names
 from pandas.core.arrays.datetimes import (
     DatetimeArrayMixin as DatetimeArray, _to_m8)
 from pandas.core.base import _shared_docs
 import pandas.core.common as com
 from pandas.core.indexes.base import Index, _index_shared_docs
 from pandas.core.indexes.datetimelike import (
-    DatetimeIndexOpsMixin, wrap_array_method, wrap_field_accessor)
+    DatetimeIndexOpsMixin, DatetimelikeDelegateMixin)
 from pandas.core.indexes.numeric import Int64Index
 from pandas.core.ops import get_op_result_name
 import pandas.core.tools.datetimes as tools
@@ -61,7 +62,54 @@ def _new_DatetimeIndex(cls, d):
     return result
 
 
-class DatetimeIndex(DatetimeArray, DatetimeIndexOpsMixin, Int64Index):
+class DatetimeDelegateMixin(DatetimelikeDelegateMixin):
+    # Most attrs are dispatched via datetimelike_{ops,methods}
+    # Some are "raw" methods, the result is not not re-boxed in an Index
+    # We also have a few "extra" attrs, which may or may not be raw,
+    # which we we dont' want to expose in the .dt accessor.
+    _extra_methods = [
+        'to_period',
+        'to_perioddelta',
+        'to_julian_date',
+    ]
+    _extra_raw_methods = [
+        'to_pydatetime',
+        '_local_timestamps',
+        '_has_same_tz',
+    ]
+    _extra_raw_properties = [
+        '_box_func',
+        'tz', 'tzinfo',
+    ]
+    _delegated_properties = (
+        DatetimeArray._datetimelike_ops + _extra_raw_properties
+    )
+    _delegated_methods = (
+        DatetimeArray._datetimelike_methods + _extra_methods +
+        _extra_raw_methods
+    )
+    _raw_properties = {
+        'date',
+        'time',
+        'timetz',
+    } | set(DatetimeArray._bool_ops) | set(_extra_raw_properties)
+    _raw_methods = set(_extra_raw_methods)
+    _delegate_class = DatetimeArray
+
+
+@delegate_names(DatetimeArray, ["to_period", "tz_localize", "tz_convert",
+                                "day_name", "month_name"],
+                typ="method", overwrite=True)
+@delegate_names(DatetimeArray,
+                DatetimeArray._field_ops, typ="property", overwrite=True)
+@delegate_names(DatetimeArray,
+                DatetimeDelegateMixin._delegated_properties,
+                typ="property")
+@delegate_names(DatetimeArray,
+                DatetimeDelegateMixin._delegated_methods,
+                typ="method", overwrite=False)
+class DatetimeIndex(DatetimeArray, DatetimeIndexOpsMixin, Int64Index,
+                    DatetimeDelegateMixin):
     """
     Immutable ndarray of datetime64 data, represented internally as int64, and
     which can be boxed to Timestamp objects that are subclasses of datetime and
@@ -1094,44 +1142,6 @@ def _eadata(self):
     is_normalized = cache_readonly(DatetimeArray.is_normalized.fget)
     _resolution = cache_readonly(DatetimeArray._resolution.fget)
 
-    year = wrap_field_accessor(DatetimeArray.year)
-    month = wrap_field_accessor(DatetimeArray.month)
-    day = wrap_field_accessor(DatetimeArray.day)
-    hour = wrap_field_accessor(DatetimeArray.hour)
-    minute = wrap_field_accessor(DatetimeArray.minute)
-    second = wrap_field_accessor(DatetimeArray.second)
-    microsecond = wrap_field_accessor(DatetimeArray.microsecond)
-    nanosecond = wrap_field_accessor(DatetimeArray.nanosecond)
-    weekofyear = wrap_field_accessor(DatetimeArray.weekofyear)
-    week = weekofyear
-    dayofweek = wrap_field_accessor(DatetimeArray.dayofweek)
-    weekday = dayofweek
-
-    weekday_name = wrap_field_accessor(DatetimeArray.weekday_name)
-
-    dayofyear = wrap_field_accessor(DatetimeArray.dayofyear)
-    quarter = wrap_field_accessor(DatetimeArray.quarter)
-    days_in_month = wrap_field_accessor(DatetimeArray.days_in_month)
-    daysinmonth = days_in_month
-    is_month_start = wrap_field_accessor(DatetimeArray.is_month_start)
-    is_month_end = wrap_field_accessor(DatetimeArray.is_month_end)
-    is_quarter_start = wrap_field_accessor(DatetimeArray.is_quarter_start)
-    is_quarter_end = wrap_field_accessor(DatetimeArray.is_quarter_end)
-    is_year_start = wrap_field_accessor(DatetimeArray.is_year_start)
-    is_year_end = wrap_field_accessor(DatetimeArray.is_year_end)
-    is_leap_year = wrap_field_accessor(DatetimeArray.is_leap_year)
-
-    tz_localize = wrap_array_method(DatetimeArray.tz_localize, True)
-    tz_convert = wrap_array_method(DatetimeArray.tz_convert, True)
-    to_perioddelta = wrap_array_method(DatetimeArray.to_perioddelta,
-                                       False)
-    to_period = wrap_array_method(DatetimeArray.to_period, True)
-    normalize = wrap_array_method(DatetimeArray.normalize, True)
-    to_julian_date = wrap_array_method(DatetimeArray.to_julian_date,
-                                       False)
-    month_name = wrap_array_method(DatetimeArray.month_name, True)
-    day_name = wrap_array_method(DatetimeArray.day_name, True)
-
     # --------------------------------------------------------------------
 
     @Substitution(klass='DatetimeIndex')

pandas/core/indexes/timedeltas.py

@@ -15,15 +15,16 @@
 import pandas.core.dtypes.concat as _concat
 from pandas.core.dtypes.missing import isna
 
+from pandas.core.accessor import delegate_names
 from pandas.core.arrays import datetimelike as dtl
 from pandas.core.arrays.timedeltas import (
     TimedeltaArrayMixin as TimedeltaArray, _is_convertible_to_td, _to_m8)
 from pandas.core.base import _shared_docs
 import pandas.core.common as com
 from pandas.core.indexes.base import Index, _index_shared_docs
 from pandas.core.indexes.datetimelike import (
-    DatetimeIndexOpsMixin, maybe_unwrap_index, wrap_arithmetic_op,
-    wrap_array_method, wrap_field_accessor)
+    DatetimeIndexOpsMixin, DatetimelikeDelegateMixin, maybe_unwrap_index,
+    wrap_arithmetic_op)
 from pandas.core.indexes.numeric import Int64Index
 from pandas.core.ops import get_op_result_name
 from pandas.core.tools.timedeltas import _coerce_scalar_to_timedelta_type
@@ -43,8 +44,40 @@ def method(self, other):
     return method
 
 
+class TimedeltaDelegateMixin(DatetimelikeDelegateMixin):
+    # Most attrs are dispatched via datetimelike_{ops,methods}
+    # Some are "raw" methods, the result is not not re-boxed in an Index
+    # We also have a few "extra" attrs, which may or may not be raw,
+    # which we we dont' want to expose in the .dt accessor.
+    _delegate_class = TimedeltaArray
+    _delegated_properties = (TimedeltaArray._datetimelike_ops + [
+        'components',
+    ])
+    _delegated_methods = TimedeltaArray._datetimelike_methods + [
+        '_box_values',
+    ]
+    _raw_properties = {
+        'components',
+    }
+    _raw_methods = {
+        'to_pytimedelta',
+    }
+
+
+@delegate_names(TimedeltaArray,
+                ["to_pytimedelta", "total_seconds"],
+                typ="method", overwrite=True)
+@delegate_names(TimedeltaArray,
+                ["days", "seconds", "microseconds", "nanoseconds"],
+                typ="property", overwrite=True)
+@delegate_names(TimedeltaArray,
+                TimedeltaDelegateMixin._delegated_properties,
+                typ="property")
+@delegate_names(TimedeltaArray,
+                TimedeltaDelegateMixin._delegated_methods,
+                typ="method", overwrite=False)
 class TimedeltaIndex(TimedeltaArray, DatetimeIndexOpsMixin,
-                     dtl.TimelikeOps, Int64Index):
+                     dtl.TimelikeOps, Int64Index, TimedeltaDelegateMixin):
     """
     Immutable ndarray of timedelta64 data, represented internally as int64, and
     which can be boxed to timedelta objects
@@ -251,13 +284,6 @@ def _eadata(self):
         __div__ = __truediv__
         __rdiv__ = __rtruediv__
 
-    days = wrap_field_accessor(TimedeltaArray.days)
-    seconds = wrap_field_accessor(TimedeltaArray.seconds)
-    microseconds = wrap_field_accessor(TimedeltaArray.microseconds)
-    nanoseconds = wrap_field_accessor(TimedeltaArray.nanoseconds)
-
-    total_seconds = wrap_array_method(TimedeltaArray.total_seconds, True)
-
     # Compat for frequency inference, see GH#23789
     _is_monotonic_increasing = Index.is_monotonic_increasing
     _is_monotonic_decreasing = Index.is_monotonic_decreasing