make PeriodArray.__new__ more grown-up

pandas-dev · jbrockmendel · Oct 13, 2018 · Oct 13, 2018 · Oct 13, 2018 · Oct 13, 2018
commit aa7138342b0bdf69e017ab397df34c38c7ab3fe8
diff --git a/pandas/core/arrays/period.py b/pandas/core/arrays/period.py
@@ -122,7 +122,15 @@ def freq(self, value):
 
     _attributes = ["freq"]
 
-    def __new__(cls, values, freq=None, **kwargs):
+    def __new__(cls, values, freq=None, dtype=None, **kwargs):
+
+        if freq is not None:
+            # coerce freq to freq object, otherwise it can be coerced
+            # elementwise, which is slow
+            freq = Period._maybe_convert_freq(freq)
+
+        freq = dtl.validate_dtype_freq(dtype, freq)
+
         if is_period_dtype(values):
             # PeriodArray, PeriodIndex
             freq = dtl.validate_dtype_freq(values.dtype, freq)

diff --git a/pandas/core/indexes/period.py b/pandas/core/indexes/period.py
@@ -176,7 +176,6 @@ def __new__(cls, data=None, ordinal=None, freq=None, start=None, end=None,
             freq = Period._maybe_convert_freq(freq)
 
         if data is None:
-            # TODO: Remove this block and associated kwargs; GH#20535
             if ordinal is not None:
                 data = np.asarray(ordinal, dtype=np.int64)
             else: