bugfix case with bunched yearends

closed pandas-dev#14774
jbrockmendel · Nov 28, 2017 · 605c8f5 · 605c8f5
1 parent 2a0e54b
commit 605c8f5
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Showing 2 changed files with 24 additions and 4 deletions.
diff --git a/pandas/tests/tseries/offsets/test_fiscal.py b/pandas/tests/tseries/offsets/test_fiscal.py
@@ -9,6 +9,7 @@
 
 import pandas.util.testing as tm
 
+from pandas import Timestamp
 from pandas.tseries.frequencies import get_offset, _INVALID_FREQ_ERROR
 from pandas.tseries.offsets import FY5253Quarter, FY5253
 from pandas._libs.tslibs.offsets import WeekDay
@@ -604,3 +605,17 @@ def test_offset(self):
         assert_offset_equal(offset2,
                             datetime(2013, 1, 15),
                             datetime(2013, 3, 30))
+
+
+def test_bunched_yearends():
+    # GH#14774 cases with two fiscal year-ends in the same calendar-year
+    fy = FY5253(n=1, weekday=5, startingMonth=12, variation='nearest')
+    dt = Timestamp('2004-01-01')
+    assert fy.rollback(dt) == Timestamp('2002-12-28')
+    assert (-fy).apply(dt) == Timestamp('2002-12-28')
+    assert dt - fy == Timestamp('2002-12-28')
+
+    assert fy.rollforward(dt) == Timestamp('2004-01-03')
+    assert fy.apply(dt) == Timestamp('2004-01-03')
+    assert fy + dt == Timestamp('2004-01-03')
+    assert dt + fy == Timestamp('2004-01-03')
diff --git a/pandas/tseries/offsets.py b/pandas/tseries/offsets.py
@@ -1869,21 +1869,26 @@ def apply(self, other):
         elif n > 0:
             if other < prev_year:
                 n -= 2
-                # TODO: Not hit in tests
-            elif other < cur_year:
+            elif prev_year < other < cur_year:
                 n -= 1
-            elif other < next_year:
+            elif cur_year < other < next_year:
                 pass
             else:
                 assert False
         else:
             if other > next_year:
                 n += 2
-                # TODO: Not hit in tests
+                # TODO: Not hit in tests; UPDATE: looks impossible
             elif other > cur_year:
                 n += 1
             elif other > prev_year:
                 pass
+            elif (other.year == prev_year.year and other < prev_year and
+                  prev_year - other <= timedelta(6)):
+                # GH#14774, error when next_year.year == cur_year.year
+                # e.g. prev_year == datetime(2004, 1, 3),
+                # other == datetime(2004, 1, 1)
+                n -= 1
             else:
                 assert False