Fix .loc[] assignment for Modin Series (#2555)

Signed-off-by: Vasilij Litvinov <vasilij.n.litvinov@intel.com>

modin/pandas/indexing.py

@@ -384,7 +384,7 @@ def _broadcast_item(self, row_lookup, col_lookup, item, to_shape):
         """
         # It is valid to pass a DataFrame or Series to __setitem__ that is larger than
         # the target the user is trying to overwrite. This
-        if isinstance(item, (pandas.Series, pandas.DataFrame, DataFrame)):
+        if isinstance(item, (pandas.Series, pandas.DataFrame, Series, DataFrame)):
             if not all(idx in item.index for idx in row_lookup):
                 raise ValueError(
                     "Must have equal len keys and value when setting with "

modin/pandas/test/dataframe/test_indexing.py

@@ -463,6 +463,15 @@ def test_iloc_nested_assignment(data):
     df_equals(modin_df, pandas_df)
 
 
+def test_loc_series():
+    md_df, pd_df = create_test_dfs({"a": [1, 2], "b": [3, 4]})
+
+    pd_df.loc[pd_df["a"] > 1, "b"] = np.log(pd_df["b"])
+    md_df.loc[md_df["a"] > 1, "b"] = np.log(md_df["b"])
+
+    df_equals(pd_df, md_df)
+
+
 @pytest.mark.parametrize("data", test_data_values, ids=test_data_keys)
 def test_pop(request, data):
     modin_df = pd.DataFrame(data)