Patch __init__ to prevent passing invalid kwds

pandas/tests/tseries/test_offsets.py

@@ -1,3 +1,4 @@
+import inspect
 import os
 from distutils.version import LooseVersion
 from datetime import date, datetime, timedelta
@@ -17,7 +18,7 @@
                                         get_offset, get_standard_freq)
 from pandas.core.indexes.datetimes import (
     _to_m8, DatetimeIndex, _daterange_cache)
-from pandas._libs.tslibs.offsets import WeekDay, CacheableOffset
+from pandas._libs.tslibs.offsets import WeekDay, CacheableOffset, _rd_kwds
 from pandas.tseries.offsets import (BDay, CDay, BQuarterEnd, BMonthEnd,
                                     BusinessHour, WeekOfMonth, CBMonthEnd,
                                     CustomBusinessHour,
@@ -4899,3 +4900,27 @@ def test_all_offset_classes(self):
             first = Timestamp(test_values[0], tz='US/Eastern') + offset()
             second = Timestamp(test_values[1], tz='US/Eastern')
             assert first == second
+
+
+# ---------------------------------------------------------------------
+
+offset_classes = [getattr(offsets, x) for x in dir(offsets)]
+offset_classes = [x for x in offset_classes if inspect.isclass(x) and
+                  issubclass(x, DateOffset)]
+
+
+def test_valid_attributes():
+    # check that we cannot create e.g. MonthEnd(weeks=3)
+    month_classes = [x for x in offset_classes if
+                     issubclass(x, offsets.MonthOffset)]
+
+    for cls in month_classes:
+        for kwd in _rd_kwds:
+            with pytest.raises(TypeError):
+                cls(**{kwd: 3})
+
+    tick_classes = [x for x in offset_classes if issubclass(x, offsets.Tick)]
+    for cls in tick_classes:
+        for kwd in _rd_kwds:
+            with pytest.raises(TypeError):
+                cls(**{kwd: 4})

pandas/tseries/offsets.py

@@ -913,6 +913,13 @@ def next_bday(self):
 class MonthOffset(SingleConstructorOffset):
     _adjust_dst = True
 
+    def __init__(self, n=1, normalize=False):
+        self.n = n
+        self.normalize = normalize
+        self._offset = timedelta(1)
+        self._use_relativedelta = False
+        self.kwds = {}
+
     @property
     def name(self):
         if self.isAnchored:
@@ -2471,6 +2478,13 @@ class Easter(DateOffset):
     """
     _adjust_dst = True
 
+    def __init__(self, n=1, normalize=False):
+        self.n = n
+        self.normalize = normalize
+        self._offset = timedelta(1)
+        self._use_relativedelta = False
+        self.kwds = {}
+
     @apply_wraps
     def apply(self, other):
         currentEaster = easter(other.year)
@@ -2515,6 +2529,14 @@ class Tick(SingleConstructorOffset):
     _inc = Timedelta(microseconds=1000)
     _prefix = 'undefined'
 
+    def __init__(self, n=1, normalize=False):
+        # TODO: do Tick classes with normalize=True make sense?
+        self.n = n
+        self.normalize = normalize
+        self._offset = timedelta(1)
+        self._use_relativedelta = False
+        self.kwds = {}
+
     __gt__ = _tick_comp(operator.gt)
     __ge__ = _tick_comp(operator.ge)
     __lt__ = _tick_comp(operator.lt)
@@ -2573,6 +2595,7 @@ def delta(self):
     def nanos(self):
         return delta_to_nanoseconds(self.delta)
 
+    # TODO: Should Tick have its own apply_index?
     def apply(self, other):
         # Timestamp can handle tz and nano sec, thus no need to use apply_wraps
         if isinstance(other, Timestamp):