✅ Added tests for converting to string

tests/unit/test_sharepoint.py

@@ -3,29 +3,53 @@
 import pandas as pd
 from viadot.sources import Sharepoint
 
+DUMMY_CREDS = {"site": "test", "username": "test2", "password": "test"}
+SAMPLE_DF = pd.DataFrame(
+    {
+        "int_col": [1, 2, 3, 4, 5, None],
+        "float_col": [1.1, 2.2, 3.3, 3.0, 5.5, 6.6],
+        "str_col": ["a", "b", "c", "d", "e", "f"],
+        "nan_col": [None, None, None, None, None, None],
+        "mixed_col": [1, "text", None, None, 4.2, "text2"],
+    }
+)
+
 
 class SharepointMock(Sharepoint):
     def _download_excel(self, url=None):
         return pd.ExcelFile(Path("tests/unit/test_file.xlsx"))
 
 
 def test_sharepoint_default_na():
-    dummy_creds = {"site": "test", "username": "test2", "password": "test"}
-
-    s = SharepointMock(credentials=dummy_creds)
+    s = SharepointMock(credentials=DUMMY_CREDS)
     df = s.to_df(url="test", na_values=Sharepoint.DEFAULT_NA_VALUES)
 
     assert not df.empty
     assert "NA" not in list(df["col_a"])
 
 
 def test_sharepoint_custom_na():
-    dummy_creds = {"site": "test", "username": "test", "password": "test"}
-
-    s = SharepointMock(credentials=dummy_creds)
+    s = SharepointMock(credentials=DUMMY_CREDS)
     df = s.to_df(
         url="test", na_values=[v for v in Sharepoint.DEFAULT_NA_VALUES if v != "NA"]
     )
 
     assert not df.empty
     assert "NA" in list(df["col_a"])
+
+
+def test_sharepoint_convert_all_to_string_type():
+    s = SharepointMock(credentials=DUMMY_CREDS)
+    converted_df = s._convert_all_to_string_type(df=SAMPLE_DF)
+
+    assert not converted_df.empty
+    assert (converted_df["nan_col"] == None).all()
+
+
+def test_sharepoint_convert_empty_columns_to_string():
+    s = SharepointMock(credentials=DUMMY_CREDS)
+    converted_df = s._empty_column_to_string(df=SAMPLE_DF)
+
+    assert not converted_df.empty
+    assert converted_df["float_col"].dtype == float
+    assert converted_df["nan_col"].dtype == "string"