add deleted tests and whatsnew

Author: charlesdong1991

doc/source/whatsnew/v0.25.0.rst

@@ -18,10 +18,7 @@ including other versions of pandas.
 
 Other Enhancements
 ^^^^^^^^^^^^^^^^^^
-
--
--
--
+:func:`DataFrame.plot` allows to expose symlog scaling for axis.
 
 
 .. _whatsnew_0250.api_breaking:

pandas/tests/plotting/test_frame.py

@@ -258,6 +258,14 @@ def test_logscales(self):
         assert ax.get_xscale() == 'symlog'
         assert ax.get_yscale() == 'symlog'
 
+    @pytest.mark.parametrize("wrong_input", ["sm", "symlog"])
+    def test_invalid_logscale(self, wrong_input):
+        df = DataFrame({'a': np.arange(100)}, index=np.arange(100))
+
+        msg = "Valid inputs are boolean, None and 'sym'."
+        with pytest.raises(ValueError, match=msg):
+            df.plot(logy=wrong_input)
+
     @pytest.mark.slow
     def test_xcompat(self):
         import pandas as pd