BUG: PeriodIndex slices with out of bounds results incorrect

Author: sinhrks

doc/source/release.rst

@@ -527,6 +527,7 @@ Bug Fixes
   (:issue:`7105`)
 - Bug in ``DatetimeIndex`` specifying ``freq`` raises ``ValueError`` when passed value is too short (:issue:`7098`)
 - Fixed a bug with the `info` repr not honoring the `display.max_info_columns` setting (:issue:`6939`)
+- Bug ``PeriodIndex`` string slicing with out of bounds values (:issue:`5407`)
 
 pandas 0.13.1
 -------------

pandas/tseries/period.py

@@ -730,6 +730,12 @@ def __iter__(self):
         for val in self.values:
             yield Period(ordinal=val, freq=self.freq)
 
+    def searchsorted(self, key, side='left'):
+        if isinstance(key, compat.string_types):
+            key = Period(key, freq=self.freq).ordinal
+
+        return self.values.searchsorted(key, side=side)
+
     @property
     def is_all_dates(self):
         return True

pandas/tseries/tests/test_period.py

@@ -1959,6 +1959,23 @@ def test_range_slice_seconds(self):
             for d in ['2013/01/01', '2013/01', '2013']:
                 assert_series_equal(s[d:], s)
 
+    def test_range_slice_outofbounds(self):
+        # GH 5407
+        didx = DatetimeIndex(start='2013/10/01', freq='D', periods=10)
+        pidx = PeriodIndex(start='2013/10/01', freq='D', periods=10)
+
+        for idx in [didx, pidx]:
+            df = DataFrame(dict(units=[100 + i for i in range(10)]), index=idx)
+            empty = DataFrame(index=DatetimeIndex([], freq='D'), columns=['units'])
+
+            tm.assert_frame_equal(df['2013/09/01':'2013/09/30'], empty)
+            tm.assert_frame_equal(df['2013/09/30':'2013/10/02'], df.iloc[:2])
+            tm.assert_frame_equal(df['2013/10/01':'2013/10/02'], df.iloc[:2])
+            tm.assert_frame_equal(df['2013/10/02':'2013/09/30'], empty)
+            tm.assert_frame_equal(df['2013/10/15':'2013/10/17'], empty)
+            tm.assert_frame_equal(df['2013/06':'2013/09'], empty)
+            tm.assert_frame_equal(df['2013/11':'2013/12'], empty)
+
     def test_pindex_qaccess(self):
         pi = PeriodIndex(['2Q05', '3Q05', '4Q05', '1Q06', '2Q06'], freq='Q')
         s = Series(np.random.rand(len(pi)), index=pi).cumsum()