CLN: libperiod (#31527)

Author: jbrockmendel

pandas/_libs/tslibs/period.pyx

@@ -473,9 +473,6 @@ cdef int DtoQ_yq(int64_t ordinal, asfreq_info *af_info, int *year) nogil:
         int quarter
 
     pandas_datetime_to_datetimestruct(ordinal, NPY_FR_D, &dts)
-    # TODO: Another version of this function used
-    # date_info_from_days_and_time(&dts, unix_date, 0)
-    # instead of pandas_datetime_to_datetimestruct; is one more performant?
     if af_info.to_end != 12:
         dts.month -= af_info.to_end
         if dts.month <= 0:
@@ -516,7 +513,7 @@ cdef int64_t asfreq_DTtoW(int64_t ordinal, asfreq_info *af_info) nogil:
 # Conversion _from_ BusinessDay Freq
 
 cdef int64_t asfreq_BtoDT(int64_t ordinal, asfreq_info *af_info) nogil:
-    ordinal = ((ordinal + 3) // 5) * 7 + (ordinal + 3) % 5 -3
+    ordinal = ((ordinal + 3) // 5) * 7 + (ordinal + 3) % 5 - 3
     return upsample_daytime(ordinal, af_info)
 
 
@@ -753,14 +750,7 @@ cdef int64_t get_period_ordinal(npy_datetimestruct *dts, int freq) nogil:
         if fmonth == 0:
             fmonth = 12
 
-        mdiff = dts.month - fmonth
-        # TODO: Aren't the next two conditions equivalent to
-        # unconditional incrementing?
-        if mdiff < 0:
-            mdiff += 12
-        if dts.month >= fmonth:
-            mdiff += 12
-
+        mdiff = dts.month - fmonth + 12
         return (dts.year - 1970) * 4 + (mdiff - 1) // 3
 
     elif freq == FR_MTH:
@@ -804,17 +794,16 @@ cdef int64_t get_period_ordinal(npy_datetimestruct *dts, int freq) nogil:
         delta = (unix_date + 3) % 7 + 1
         # return the number of business days in full weeks plus the business
         # days in the last - possible partial - week
-        if delta <= 5:
-            return (5 * weeks) + delta - 4
-        else:
-            return (5 * weeks) + (5 + 1) - 4
+        if delta > 6:
+            # We have a Sunday, which rolls back to the previous Friday,
+            # just like Saturday, so decrement delta by 1 to treat as saturday
+            delta = 6
+        return (5 * weeks) + delta - 4
 
     elif freq_group == FR_WK:
         day_adj = freq - FR_WK
         return (unix_date + 3 - day_adj) // 7 + 1
 
-    # raise ValueError
-
 
 cdef void get_date_info(int64_t ordinal, int freq,
                         npy_datetimestruct *dts) nogil:
@@ -983,7 +972,7 @@ cdef inline int month_to_quarter(int month) nogil:
 
 @cython.wraparound(False)
 @cython.boundscheck(False)
-def dt64arr_to_periodarr(int64_t[:] dtarr, int freq, tz=None):
+def dt64arr_to_periodarr(const int64_t[:] dtarr, int freq, tz=None):
     """
     Convert array of datetime64 values (passed in as 'i8' dtype) to a set of
     periods corresponding to desired frequency, per period convention.
@@ -1383,7 +1372,7 @@ cdef int pdays_in_month(int64_t ordinal, int freq):
 
 @cython.wraparound(False)
 @cython.boundscheck(False)
-def get_period_field_arr(int code, int64_t[:] arr, int freq):
+def get_period_field_arr(int code, const int64_t[:] arr, int freq):
     cdef:
         Py_ssize_t i, sz
         int64_t[:] out
@@ -1496,7 +1485,7 @@ def extract_freq(ndarray[object] values):
 
 @cython.wraparound(False)
 @cython.boundscheck(False)
-cdef int64_t[:] localize_dt64arr_to_period(int64_t[:] stamps,
+cdef int64_t[:] localize_dt64arr_to_period(const int64_t[:] stamps,
                                            int freq, object tz):
     cdef:
         Py_ssize_t n = len(stamps)
@@ -1584,7 +1573,7 @@ cdef class _Period:
         return freq
 
     @classmethod
-    def _from_ordinal(cls, ordinal, freq):
+    def _from_ordinal(cls, ordinal: int, freq) -> "Period":
         """
         Fast creation from an ordinal and freq that are already validated!
         """
@@ -1704,7 +1693,7 @@ cdef class _Period:
         else:
             return NotImplemented
 
-    def asfreq(self, freq, how='E'):
+    def asfreq(self, freq, how='E') -> "Period":
         """
         Convert Period to desired frequency, at the start or end of the interval.
 
@@ -1735,7 +1724,7 @@ cdef class _Period:
         return Period(ordinal=ordinal, freq=freq)
 
     @property
-    def start_time(self):
+    def start_time(self) -> Timestamp:
         """
         Get the Timestamp for the start of the period.
 
@@ -1765,13 +1754,13 @@ cdef class _Period:
         return self.to_timestamp(how='S')
 
     @property
-    def end_time(self):
+    def end_time(self) -> Timestamp:
         # freq.n can't be negative or 0
         # ordinal = (self + self.freq.n).start_time.value - 1
         ordinal = (self + self.freq).start_time.value - 1
         return Timestamp(ordinal)
 
-    def to_timestamp(self, freq=None, how='start', tz=None):
+    def to_timestamp(self, freq=None, how='start', tz=None) -> Timestamp:
         """
         Return the Timestamp representation of the Period.
 
@@ -1811,17 +1800,17 @@ cdef class _Period:
         return Timestamp(dt64, tz=tz)
 
     @property
-    def year(self):
+    def year(self) -> int:
         base, mult = get_freq_code(self.freq)
         return pyear(self.ordinal, base)
 
     @property
-    def month(self):
+    def month(self) -> int:
         base, mult = get_freq_code(self.freq)
         return pmonth(self.ordinal, base)
 
     @property
-    def day(self):
+    def day(self) -> int:
         """
         Get day of the month that a Period falls on.
 
@@ -1844,7 +1833,7 @@ cdef class _Period:
         return pday(self.ordinal, base)
 
     @property
-    def hour(self):
+    def hour(self) -> int:
         """
         Get the hour of the day component of the Period.
 
@@ -1874,7 +1863,7 @@ cdef class _Period:
         return phour(self.ordinal, base)
 
     @property
-    def minute(self):
+    def minute(self) -> int:
         """
         Get minute of the hour component of the Period.
 
@@ -1898,7 +1887,7 @@ cdef class _Period:
         return pminute(self.ordinal, base)
 
     @property
-    def second(self):
+    def second(self) -> int:
         """
         Get the second component of the Period.
 
@@ -1922,12 +1911,12 @@ cdef class _Period:
         return psecond(self.ordinal, base)
 
     @property
-    def weekofyear(self):
+    def weekofyear(self) -> int:
         base, mult = get_freq_code(self.freq)
         return pweek(self.ordinal, base)
 
     @property
-    def week(self):
+    def week(self) -> int:
         """
         Get the week of the year on the given Period.
 
@@ -1957,7 +1946,7 @@ cdef class _Period:
         return self.weekofyear
 
     @property
-    def dayofweek(self):
+    def dayofweek(self) -> int:
         """
         Day of the week the period lies in, with Monday=0 and Sunday=6.
 
@@ -2008,7 +1997,7 @@ cdef class _Period:
         return pweekday(self.ordinal, base)
 
     @property
-    def weekday(self):
+    def weekday(self) -> int:
         """
         Day of the week the period lies in, with Monday=0 and Sunday=6.
 
@@ -2061,7 +2050,7 @@ cdef class _Period:
         return self.dayofweek
 
     @property
-    def dayofyear(self):
+    def dayofyear(self) -> int:
         """
         Return the day of the year.
 
@@ -2096,12 +2085,12 @@ cdef class _Period:
         return pday_of_year(self.ordinal, base)
 
     @property
-    def quarter(self):
+    def quarter(self) -> int:
         base, mult = get_freq_code(self.freq)
         return pquarter(self.ordinal, base)
 
     @property
-    def qyear(self):
+    def qyear(self) -> int:
         """
         Fiscal year the Period lies in according to its starting-quarter.
 
@@ -2145,7 +2134,7 @@ cdef class _Period:
         return pqyear(self.ordinal, base)
 
     @property
-    def days_in_month(self):
+    def days_in_month(self) -> int:
         """
         Get the total number of days in the month that this period falls on.
 
@@ -2179,7 +2168,7 @@ cdef class _Period:
         return pdays_in_month(self.ordinal, base)
 
     @property
-    def daysinmonth(self):
+    def daysinmonth(self) -> int:
         """
         Get the total number of days of the month that the Period falls in.
 
@@ -2209,7 +2198,7 @@ cdef class _Period:
         return Period(datetime.now(), freq=freq)
 
     @property
-    def freqstr(self):
+    def freqstr(self) -> str:
         return self.freq.freqstr
 
     def __repr__(self) -> str:

pandas/tests/scalar/period/test_period.py

@@ -925,7 +925,7 @@ def test_properties_secondly(self):
 
 class TestPeriodField:
     def test_get_period_field_array_raises_on_out_of_range(self):
-        msg = "Buffer dtype mismatch, expected 'int64_t' but got 'double'"
+        msg = "Buffer dtype mismatch, expected 'const int64_t' but got 'double'"
         with pytest.raises(ValueError, match=msg):
             libperiod.get_period_field_arr(-1, np.empty(1), 0)