Fix __repr__ output with display.max_rows is None (#8547)

Fixes: #6978 

This PR fixes `__repr__` output when `display.max_rows` is `None`, when it is `None` the output must have all the rows of series printed. This is already being handled as part of dataframe.

Authors:
  - GALI PREM SAGAR (https://github.com/galipremsagar)

Approvers:
  - Michael Wang (https://github.com/isVoid)

URL: #8547

python/cudf/cudf/core/series.py

@@ -1226,7 +1226,7 @@ def __repr__(self):
             if get_option("display.max_rows") == 0
             else get_option("display.max_rows")
         )
-        if len(self) > max_rows and max_rows != 0:
+        if max_rows not in (0, None) and len(self) > max_rows:
             top = self.head(int(max_rows / 2 + 1))
             bottom = self.tail(int(max_rows / 2 + 1))
             preprocess = cudf.concat([top, bottom])
@@ -1254,7 +1254,7 @@ def __repr__(self):
         ):
             min_rows = (
                 height
-                if get_option("display.max_rows") == 0
+                if get_option("display.min_rows") == 0
                 else get_option("display.min_rows")
             )
             show_dimensions = get_option("display.show_dimensions")

python/cudf/cudf/tests/test_repr.py

@@ -86,12 +86,12 @@ def test_null_dataframe(ncols):
 
 
 @pytest.mark.parametrize("dtype", repr_categories)
-@pytest.mark.parametrize("nrows", [0, 1, 2, 9, 10, 11, 19, 20, 21])
+@pytest.mark.parametrize("nrows", [None, 0, 1, 2, 9, 10, 11, 19, 20, 21])
 def test_full_series(nrows, dtype):
     size = 20
     ps = pd.Series(np.random.randint(0, 100, size)).astype(dtype)
     sr = cudf.from_pandas(ps)
-    pd.options.display.max_rows = int(nrows)
+    pd.options.display.max_rows = nrows
     assert ps.__repr__() == sr.__repr__()
     pd.reset_option("display.max_rows")