change to IO and add comment

Author: AntonioAndraues

doc/source/whatsnew/v1.0.0.rst

@@ -317,6 +317,7 @@ I/O
 - Bug in :func:`read_hdf` closing stores that it didn't open when Exceptions are raised (:issue:`28699`)
 - Bug in :meth:`DataFrame.read_json` where using ``orient="index"`` would not maintain the order (:issue:`28557`)
 - Bug in :meth:`DataFrame.to_html` where the length of the ``formatters`` argument was not verified (:issue:`28469`)
+- Bug in :meth:`pandas.io.formats.style.Styler` formatting for floating values not displaying decimals correctly (:issue:`13257`)
 
 Plotting
 ^^^^^^^^
@@ -371,7 +372,6 @@ Other
 - Bug in :meth:`Series.diff` where a boolean series would incorrectly raise a ``TypeError`` (:issue:`17294`)
 - :meth:`Series.append` will no longer raise a ``TypeError`` when passed a tuple of ``Series`` (:issue:`28410`)
 - Fix corrupted error message when calling ``pandas.libs._json.encode()`` on a 0d array (:issue:`18878`)
-- Bug in :meth:`pandas.io.formats.style.Styler` formatting for floating values not displaying decimals correctly (:issue:`13257`)
 
 .. _whatsnew_1000.contributors:
 

pandas/tests/io/formats/test_style.py

@@ -1158,6 +1158,7 @@ def test_display_format_raises(self):
             df.style.format(True)
 
     def test_display_set_precision(self):
+        # Issue #13257
         df = pd.DataFrame(data=[[1.0, 2.0090], [3.2121, 4.566]], columns=["a", "b"])
         s = Styler(df)