TST: test for to_csv to succeed with deprecated options (GH3701)

Author: jreback

RELEASE.rst

@@ -178,6 +178,7 @@ pandas 0.11.1
   - ``convert_objects`` with ``convert_dates='coerce'`` was parsing some single-letter strings
      into today's date
   - ``DataFrame.from_records`` did not accept empty recarrays (GH3682_)
+  - ``DataFrame.to_csv`` will succeed with the deprecated option ``nanRep``, @tdsmith
 
 .. _GH3164: https://github.com/pydata/pandas/issues/3164
 .. _GH2786: https://github.com/pydata/pandas/issues/2786

pandas/tests/test_frame.py

@@ -4726,6 +4726,16 @@ def test_float_none_comparison(self):
 
         self.assertRaises(TypeError, df.__eq__, None)
 
+    def test_to_csv_deprecated_options(self):
+
+        pname = '__tmp_to_csv_deprecated_options__'
+        with ensure_clean(pname) as path:
+
+            self.tsframe[1:3] = np.nan
+            self.tsframe.to_csv(path, nanRep='foo')
+            recons = read_csv(path,index_col=0,parse_dates=[0],na_values=['foo'])
+            assert_frame_equal(self.tsframe, recons)
+
     def test_to_csv_from_csv(self):
 
         pname = '__tmp_to_csv_from_csv__'