add test

pandas-dev · attack68 · Nov 12, 2021 · Nov 12, 2021 · Nov 12, 2021 · Nov 12, 2021
commit 89225de96196858a764c05cb0e203d8efe55f39e
diff --git a/pandas/tests/io/formats/test_to_latex.py b/pandas/tests/io/formats/test_to_latex.py
@@ -1514,3 +1514,15 @@ def test_get_strrow_multindex_multicolumn(self, row_num, expected):
         )
 
         assert row_string_converter.get_strrow(row_num=row_num) == expected
+
+    def test_future_warning(self):
+        df = DataFrame([[1]])
+        msg = (
+            "In future versions `DataFrame.to_latex` is expected to utilise the base "
+            "implementation of `Styler.to_latex` for formatting and rendering. "
+            "The arguments signature may therefore change. It is recommended instead to"
+            "use `DataFrame.style.to_latex` which also contains additional "
+            "functionality."
+        )
+        with tm.assert_produces_warning(FutureWarning, match=msg):
+            df.to_latex()