Review (jreback)

Author: h-vetinari

pandas/core/frame.py

@@ -60,8 +60,7 @@
  is_sequence,
  is_named_tuple)
 from pandas.core.dtypes.concat import _get_sliced_frame_result_type
-from pandas.core.dtypes.generic import (ABCSeries, ABCIndexClass,
- ABCMultiIndex, ABCDataFrame)
+from pandas.core.dtypes.generic import ABCSeries, ABCIndexClass, ABCMultiIndex
 from pandas.core.dtypes.missing import isna, notna
 
 
@@ -3955,16 +3954,17 @@ def set_index(self, keys, drop=True, append=False, inplace=False,
  keys = [keys]
 
  missing = []
- for x in keys:
- if (is_scalar(x) or isinstance(x, tuple)) and x in self:
+ for col in keys:
+ if (is_scalar(col) or isinstance(col, tuple)) and col in self:
+ # tuples can be both column keys or list-likes
+ # if they are valid column keys, everything is fine
  continue
- elif is_scalar(x) and x not in self:
- # a tuple gets tried as column key first;
- # otherwise considered as a list-like; i.e. not missing
- missing.append(x)
- elif (not is_list_like(x) or isinstance(x, set)
- or isinstance(x, ABCDataFrame)
- or (isinstance(x, np.ndarray) and x.ndim > 1)):
+ elif is_scalar(col) and col not in self:
+ # tuples that are not column keys are considered list-like,
+ # not considered missing
+ missing.append(col)
+ elif (not is_list_like(col) or isinstance(col, set)
+ or getattr(col, 'ndim', 1) > 1):
  raise TypeError('The parameter "keys" may only contain a '
  'combination of valid column keys and '
  'one-dimensional list-likes')