CLN: Change path argument name to path_or_buf

This way, the Series.to_csv naming convention for this argument will
conform to the DataFrame.to_csv naming convention.

Author: dahlbaek

pandas/core/series.py

@@ -2878,7 +2878,7 @@ def from_csv(cls, path, sep=',', parse_dates=True, header=None,
 
         return result
 
-    def to_csv(self, path=None, index=True, sep=",", na_rep='',
+    def to_csv(self, path_or_buf=None, index=True, sep=",", na_rep='',
                float_format=None, header=False, index_label=None,
                mode='w', encoding=None, compression=None, date_format=None,
                decimal='.'):
@@ -2920,8 +2920,11 @@ def to_csv(self, path=None, index=True, sep=",", na_rep='',
         """
         from pandas.core.frame import DataFrame
         df = DataFrame(self)
-        # result is only a string if no path provided, otherwise None
-        result = df.to_csv(path, index=index, sep=sep, na_rep=na_rep,
+
+        # ensure backwards compatibility with path argument
+        path_or_buf = kwargs.pop('path', path_or_buf)
+        # result is only a string if no path_or_buf provided, otherwise None
+        result = df.to_csv(path_or_buf, index=index, sep=sep, na_rep=na_rep,
                            float_format=float_format, header=header,
                            index_label=index_label, mode=mode,
                            encoding=encoding, compression=compression,