BUG-22984 Fix whatsnew and add test

Author: JustinZhengBC

doc/source/whatsnew/v0.24.0.txt

@@ -194,7 +194,6 @@ Other Enhancements
 - :meth:`Index.to_frame` now supports overriding column name(s) (:issue:`22580`).
 - New attribute :attr:`__git_version__` will return git commit sha of current build (:issue:`21295`).
 - Compatibility with Matplotlib 3.0 (:issue:`22790`).
-- Representation of :class:`DataFrame` fills up the terminal window better
 
 .. _whatsnew_0240.api_breaking:
 
@@ -803,6 +802,7 @@ I/O
 - :func:`read_sas()` will correctly parse sas7bdat files with data page types having also bit 7 set (so page type is 128 + 256 = 384) (:issue:`16615`)
 - Bug in :meth:`detect_client_encoding` where potential ``IOError`` goes unhandled when importing in a mod_wsgi process due to restricted access to stdout. (:issue:`21552`)
 - Bug in :func:`to_string()` that broke column alignment when ``index=False`` and width of first column's values is greater than the width of first column's header (:issue:`16839`, :issue:`13032`)
+- Bug in :func:`to_string()` that caused representations of :class:`DataFrame` to not take up the whole window (:issue:`22984`)
 
 Plotting
 ^^^^^^^^

pandas/tests/io/formats/test_format.py

@@ -343,6 +343,16 @@ def test_repr_truncates_terminal_size(self):
 
         assert df2.columns[0] in result.split('\n')[0]
 
+        # GH 22984 ensure entire window is filled
+        terminal_size = (80, 24)
+        df = pd.DataFrame(np.random.rand(1,7))
+        p1 = mock.patch('pandas.io.formats.console.get_terminal_size',
+                        return_value=terminal_size)
+        p2 = mock.patch('pandas.io.formats.format.get_terminal_size',
+                        return_value=terminal_size)
+        with p1, p2:
+            assert "..." not in str(df)
+
     def test_repr_max_columns_max_rows(self):
         term_width, term_height = get_terminal_size()
         if term_width < 10 or term_height < 10: