REF: move mixins, repr_attrs to liboffsets

doc/source/reference/offset_frequency.rst

@@ -1056,6 +1056,7 @@ Methods
     Tick.is_anchored
     Tick.is_on_offset
     Tick.__call__
+    Tick.apply
 
 Day
 ---
@@ -1088,6 +1089,7 @@ Methods
     Day.is_anchored
     Day.is_on_offset
     Day.__call__
+    Day.apply
 
 Hour
 ----
@@ -1120,6 +1122,7 @@ Methods
     Hour.is_anchored
     Hour.is_on_offset
     Hour.__call__
+    Hour.apply
 
 Minute
 ------
@@ -1152,6 +1155,7 @@ Methods
     Minute.is_anchored
     Minute.is_on_offset
     Minute.__call__
+    Minute.apply
 
 Second
 ------
@@ -1184,6 +1188,7 @@ Methods
     Second.is_anchored
     Second.is_on_offset
     Second.__call__
+    Second.apply
 
 Milli
 -----
@@ -1216,6 +1221,7 @@ Methods
     Milli.is_anchored
     Milli.is_on_offset
     Milli.__call__
+    Milli.apply
 
 Micro
 -----
@@ -1248,6 +1254,7 @@ Methods
     Micro.is_anchored
     Micro.is_on_offset
     Micro.__call__
+    Micro.apply
 
 Nano
 ----
@@ -1280,6 +1287,7 @@ Methods
     Nano.is_anchored
     Nano.is_on_offset
     Nano.__call__
+    Nano.apply
 
 BDay
 ----

pandas/_libs/tslibs/offsets.pxd

@@ -1,3 +1,2 @@
 cdef to_offset(object obj)
 cdef bint is_offset_object(object obj)
-cdef bint is_tick_object(object obj)

pandas/_libs/tslibs/offsets.pyx

@@ -21,7 +21,7 @@ cnp.import_array()
 from pandas._libs.tslibs cimport util
 from pandas._libs.tslibs.util cimport is_integer_object
 
-from pandas._libs.tslibs.base cimport ABCTick, ABCTimestamp
+from pandas._libs.tslibs.base cimport ABCTick, ABCTimestamp, is_tick_object
 
 from pandas._libs.tslibs.ccalendar import MONTHS, DAYS
 from pandas._libs.tslibs.ccalendar cimport get_days_in_month, dayofweek
@@ -93,10 +93,6 @@ cdef bint is_offset_object(object obj):
     return isinstance(obj, _BaseOffset)
 
 
-cdef bint is_tick_object(object obj):
-    return isinstance(obj, _Tick)
-
-
 cdef to_offset(object obj):
     """
     Wrap pandas.tseries.frequencies.to_offset to keep centralize runtime
@@ -335,7 +331,7 @@ def to_dt64D(dt):
 # Validation
 
 
-def validate_business_time(t_input):
+def _validate_business_time(t_input):
     if isinstance(t_input, str):
         try:
             t = time.strptime(t_input, '%H:%M')
@@ -528,6 +524,21 @@ class _BaseOffset:
         out = f'<{n_str}{className}{plural}{self._repr_attrs()}>'
         return out
 
+    def _repr_attrs(self) -> str:
+        exclude = {"n", "inc", "normalize"}
+        attrs = []
+        for attr in sorted(self.__dict__):
+            if attr.startswith("_") or attr == "kwds":
+                continue
+            elif attr not in exclude:
+                value = getattr(self, attr)
+                attrs.append(f"{attr}={value}")
+
+        out = ""
+        if attrs:
+            out += ": " + ", ".join(attrs)
+        return out
+
     @property
     def name(self) -> str:
         return self.rule_code
@@ -790,6 +801,97 @@ class BusinessMixin:
         return out
 
 
+class BusinessHourMixin(BusinessMixin):
+    _adjust_dst = False
+
+    def __init__(self, start="09:00", end="17:00", offset=timedelta(0)):
+        # must be validated here to equality check
+        if np.ndim(start) == 0:
+            # i.e. not is_list_like
+            start = [start]
+        if not len(start):
+            raise ValueError("Must include at least 1 start time")
+
+        if np.ndim(end) == 0:
+            # i.e. not is_list_like
+            end = [end]
+        if not len(end):
+            raise ValueError("Must include at least 1 end time")
+
+        start = np.array([_validate_business_time(x) for x in start])
+        end = np.array([_validate_business_time(x) for x in end])
+
+        # Validation of input
+        if len(start) != len(end):
+            raise ValueError("number of starting time and ending time must be the same")
+        num_openings = len(start)
+
+        # sort starting and ending time by starting time
+        index = np.argsort(start)
+
+        # convert to tuple so that start and end are hashable
+        start = tuple(start[index])
+        end = tuple(end[index])
+
+        total_secs = 0
+        for i in range(num_openings):
+            total_secs += self._get_business_hours_by_sec(start[i], end[i])
+            total_secs += self._get_business_hours_by_sec(
+                end[i], start[(i + 1) % num_openings]
+            )
+        if total_secs != 24 * 60 * 60:
+            raise ValueError(
+                "invalid starting and ending time(s): "
+                "opening hours should not touch or overlap with "
+                "one another"
+            )
+
+        object.__setattr__(self, "start", start)
+        object.__setattr__(self, "end", end)
+        object.__setattr__(self, "_offset", offset)
+
+    def _repr_attrs(self) -> str:
+        out = super()._repr_attrs()
+        hours = ",".join(
+            f'{st.strftime("%H:%M")}-{en.strftime("%H:%M")}'
+            for st, en in zip(self.start, self.end)
+        )
+        attrs = [f"{self._prefix}={hours}"]
+        out += ": " + ", ".join(attrs)
+        return out
+
+    def _get_business_hours_by_sec(self, start, end):
+        """
+        Return business hours in a day by seconds.
+        """
+        # create dummy datetime to calculate business hours in a day
+        dtstart = datetime(2014, 4, 1, start.hour, start.minute)
+        day = 1 if start < end else 2
+        until = datetime(2014, 4, day, end.hour, end.minute)
+        return int((until - dtstart).total_seconds())
+
+    def _get_closing_time(self, dt):
+        """
+        Get the closing time of a business hour interval by its opening time.
+
+        Parameters
+        ----------
+        dt : datetime
+            Opening time of a business hour interval.
+
+        Returns
+        -------
+        result : datetime
+            Corresponding closing time.
+        """
+        for i, st in enumerate(self.start):
+            if st.hour == dt.hour and st.minute == dt.minute:
+                return dt + timedelta(
+                    seconds=self._get_business_hours_by_sec(st, self.end[i])
+                )
+        assert False
+
+
 class CustomMixin:
     """
     Mixin for classes that define and validate calendar, holidays,
@@ -809,6 +911,31 @@ class CustomMixin:
         object.__setattr__(self, "calendar", calendar)
 
 
+class WeekOfMonthMixin:
+    """
+    Mixin for methods common to WeekOfMonth and LastWeekOfMonth.
+    """
+
+    @apply_wraps
+    def apply(self, other):
+        compare_day = self._get_offset_day(other)
+
+        months = self.n
+        if months > 0 and compare_day > other.day:
+            months -= 1
+        elif months <= 0 and compare_day < other.day:
+            months += 1
+
+        shifted = shift_month(other, months, "start")
+        to_day = self._get_offset_day(shifted)
+        return shift_day(shifted, to_day - shifted.day)
+
+    def is_on_offset(self, dt) -> bool:
+        if self.normalize and not is_normalized(dt):
+            return False
+        return dt.day == self._get_offset_day(dt)
+
+
 # ----------------------------------------------------------------------
 # RelativeDelta Arithmetic
 

pandas/_libs/tslibs/period.pyx

@@ -37,7 +37,7 @@ cdef extern from "src/datetime/np_datetime.h":
 
 cimport pandas._libs.tslibs.util as util
 
-from pandas._libs.tslibs.base cimport ABCPeriod, is_period_object
+from pandas._libs.tslibs.base cimport ABCPeriod, is_period_object, is_tick_object
 
 from pandas._libs.tslibs.timestamps import Timestamp
 from pandas._libs.tslibs.timezones cimport is_utc, is_tzlocal, get_dst_info
@@ -68,7 +68,7 @@ from pandas._libs.tslibs.nattype cimport (
     c_NaT as NaT,
     c_nat_strings as nat_strings,
 )
-from pandas._libs.tslibs.offsets cimport to_offset, is_tick_object
+from pandas._libs.tslibs.offsets cimport to_offset
 from pandas._libs.tslibs.tzconversion cimport tz_convert_utc_to_tzlocal