fix conflicting wrapping behavior for missing (None) values

Author: astanin

tabulate/__init__.py

@@ -1661,7 +1661,7 @@ def _wrap_text_to_colwidths(list_of_lists, colwidths, numparses=True, missingval
                 # explicit than just `str` of the object. Also doesn't work for
                 # custom floatfmt/intfmt, nor with any missing/blank cells.
                 casted_cell = (
-                    missingval if cell is None else str(cell) if cell == '' or _isnumber(cell) else _type(cell, numparse)(cell)
+                    missingval if cell is None else str(cell) if cell == '' or _isnumber(cell) else str(_type(cell, numparse)(cell))
                 )
                 wrapped = [
                     "\n".join(wrapper.wrap(line))

test/test_textwrapper.py

@@ -282,7 +282,7 @@ def test_wrap_optional_bool_strs():
         "| First   | True   |",
         "| Entry   |        |",
         "+---------+--------+",
-        "| Second  | None   |",
+        "| Second  |        |",
         "| Entry   |        |",
         "+---------+--------+",
     ]