Merge pull request #4490 from jreback/hdf_fix2

TST: reverse hdf_fix

Author: jreback

pandas/io/pytables.py

@@ -332,11 +332,12 @@ def __len__(self):
     def __unicode__(self):
         output = '%s\nFile path: %s\n' % (type(self), pprint_thing(self._path))
         if self.is_open:
-            if len(list(self.keys())):
+            lkeys = list(self.keys())
+            if len(lkeys):
                 keys   = []
                 values = []
 
-                for k in self.keys():
+                for k in lkeys:
                     try:
                         s = self.get_storer(k)
                         if s is not None:

pandas/io/tests/test_pytables.py

@@ -11,7 +11,7 @@
 
 import pandas
 from pandas import (Series, DataFrame, Panel, MultiIndex, bdate_range,
-                    date_range, Index, DatetimeIndex)
+                    date_range, Index, DatetimeIndex, isnull)
 from pandas.io.pytables import (HDFStore, get_store, Term, read_hdf,
                                 IncompatibilityWarning, PerformanceWarning,
                                 AttributeConflictWarning, DuplicateWarning,
@@ -2404,14 +2404,11 @@ def test_frame_select(self):
     def test_string_select(self):
 
         # GH 2973
-
-        df = tm.makeTimeDataFrame()
-
         with ensure_clean(self.path) as store:
 
+            df = tm.makeTimeDataFrame()
 
             # test string ==/!=
-
             df['x'] = 'none'
             df.ix[2:7,'x'] = ''
 
@@ -2421,25 +2418,18 @@ def test_string_select(self):
             expected = df[df.x == 'none']
             assert_frame_equal(result,expected)
 
-            print("bogus test")
-            print(df)
-            print(store)
             result = store.select('df',Term('x!=none'))
-            print(result)
             expected = df[df.x != 'none']
-            print(expected)
             assert_frame_equal(result,expected)
 
             df2 = df.copy()
-            df2.x[df2.x==''] = np.nan
+            df2.loc[df2.x=='','x'] = np.nan
 
-            from pandas import isnull
             store.append('df2',df2,data_columns=['x'])
             result = store.select('df2',Term('x!=none'))
             expected = df2[isnull(df2.x)]
             assert_frame_equal(result,expected)
 
-
             # int ==/!=
             df['int'] = 1
             df.ix[2:7,'int'] = 2