added unit-test to highlight issue pandas-dev#54564

Author: burnpanck

pandas/tests/io/data/excel/test6.xls

@@ -1,5 +1,6 @@
 import io
 
+import numpy as np
 import pytest
 
 import pandas as pd
@@ -44,6 +45,17 @@ def test_read_xlsx_fails(datapath):
         pd.read_excel(path, engine="xlrd")
 
 
+def test_nan_in_xls(datapath):
+    # GH 54564
+    path = datapath("io", "data", "excel", "test6.xls")
+
+    expected = pd.DataFrame(np.r_[:3, np.nan].reshape(2, 2))
+
+    result = pd.read_excel(path)
+
+    tm.assert_frame_equal(result, expected)
+
+
 @pytest.mark.parametrize(
     "file_header",
     [