converted print statements to errors/warnings (#137)

* Converted print statements to errors/warnings; updated tests

* fix: Convert error to warning

* test: reinstate not impletmented extension test; added check for warning

* test: removed duplicate .svg test

---------

Co-authored-by: Ethan Moss <[email protected]>

src/transport_performance/gtfs/validation.py

@@ -12,6 +12,7 @@
 import plotly.io as plotly_io
 from pretty_html_table import build_table
 import zipfile
+import warnings
 import pathlib
 from typing import Union
 from plotly.graph_objects import Figure as PlotlyFigure
@@ -224,7 +225,9 @@ def print_alerts(self, alert_type="error"):
             elif isinstance(msgs, str):
                 print(msgs)
         except KeyError:
-            print(f"No alerts of type {alert_type} were found.")
+            warnings.warn(
+                f"No alerts of type {alert_type} were found.", UserWarning
+            )
 
         return None
 
@@ -236,6 +239,7 @@ def clean_feed(self):
             # shows that shapes.txt is optional file.
             self.feed = self.feed.clean()
         except KeyError:
+            # TODO: Issue 74 - Improve this to clean feed when KeyError raised
             print("KeyError. Feed was not cleaned.")
 
     def viz_stops(
@@ -273,7 +277,9 @@ def viz_stops(
 
         pre, ext = os.path.splitext(out_pth)
         if ext != ".html":
-            print(f"{ext} format not implemented. Writing to .html")
+            warnings.warn(
+                f"{ext} format not implemented. Saving as .html", UserWarning
+            )
             out_pth = os.path.normpath(pre + ".html")
 
         # geoms defence
@@ -320,7 +326,13 @@ def viz_stops(
                 m.fit_bounds(m.get_bounds())
             m.save(out_pth)
         except KeyError:
-            print("Key Error. Map was not written.")
+            # KeyError inside of an except KeyError here. This is to provide
+            # a more detaailed error message on why a KeyError is being raised.
+            raise KeyError(
+                "The stops table has no 'stop_code' column. While "
+                "this is an optional field in a GTFS file, it "
+                "raises an error through the gtfs-kit package."
+            )
 
     def _order_dataframe_by_day(
         self, df: pd.DataFrame, day_column_name: str = "day"

tests/gtfs/test_validation.py

@@ -117,8 +117,7 @@ def test_is_valid(self, gtfs_fixture):
             found_cols == exp_cols
         ).all(), f"Expected columns {exp_cols}. Found: {found_cols}"
 
-    @patch("builtins.print")
-    def test_print_alerts_defence(self, mocked_print, gtfs_fixture):
+    def test_print_alerts_defence(self, gtfs_fixture):
         """Check defensive behaviour of print_alerts()."""
         with pytest.raises(
             AttributeError,
@@ -127,11 +126,10 @@ def test_print_alerts_defence(self, mocked_print, gtfs_fixture):
             gtfs_fixture.print_alerts()
 
         gtfs_fixture.is_valid()
-        gtfs_fixture.print_alerts(alert_type="doesnt_exist")
-        fun_out = mocked_print.mock_calls
-        assert fun_out == [
-            call("No alerts of type doesnt_exist were found.")
-        ], f"Expected a print about alert_type but found: {fun_out}"
+        with pytest.warns(
+            UserWarning, match="No alerts of type doesnt_exist were found."
+        ):
+            gtfs_fixture.print_alerts(alert_type="doesnt_exist")
 
     @patch("builtins.print")  # testing print statements
     def test_print_alerts_single_case(self, mocked_print, gtfs_fixture):
@@ -160,8 +158,7 @@ def test_print_alerts_multi_case(self, mocked_print, gtfs_fixture):
             call("Unrecognized column vehicle_journey_code"),
         ], f"Expected print statements about GTFS warnings. Found: {fun_out}"
 
-    @patch("builtins.print")
-    def test_viz_stops_defence(self, mocked_print, tmpdir, gtfs_fixture):
+    def test_viz_stops_defence(self, tmpdir, gtfs_fixture):
         """Check defensive behaviours of viz_stops()."""
         tmp = os.path.join(tmpdir, "somefile.html")
         with pytest.raises(
@@ -182,13 +179,15 @@ def test_viz_stops_defence(self, mocked_print, tmpdir, gtfs_fixture):
             match="`geom_crs`.*string or integer. Found <class 'float'>",
         ):
             gtfs_fixture.viz_stops(out_pth=tmp, geom_crs=1.1)
-        # check missing stop_id results in print instead of exception
+        # check missing stop_id results in an informative error message
         gtfs_fixture.feed.stops.drop("stop_id", axis=1, inplace=True)
-        gtfs_fixture.viz_stops(out_pth=tmp)
-        fun_out = mocked_print.mock_calls
-        assert fun_out == [
-            call("Key Error. Map was not written.")
-        ], f"Expected confirmation that map was not written. Found: {fun_out}"
+        with pytest.raises(
+            KeyError,
+            match="The stops table has no 'stop_code' column. While "
+            "this is an optional field in a GTFS file, it "
+            "raises an error through the gtfs-kit package.",
+        ):
+            gtfs_fixture.viz_stops(out_pth=tmp)
 
     @patch("builtins.print")
     def test_viz_stops_point(self, mock_print, tmpdir, gtfs_fixture):
@@ -208,18 +207,18 @@ def test_viz_stops_point(self, mock_print, tmpdir, gtfs_fixture):
         ), f"{no_parent_pth} was expected to exist but it was not found."
         # check behaviour when not implemented fileext used
         tmp1 = os.path.join(tmpdir, "points2.svg")
-        gtfs_fixture.viz_stops(out_pth=pathlib.Path(tmp1))
+        with pytest.warns(
+            UserWarning,
+            match=".svg format not implemented. Saving as .html",
+        ):
+            gtfs_fixture.viz_stops(out_pth=pathlib.Path(tmp1))
         # need to use regex for the first print statement, as tmpdir will
         # change.
         start_pat = re.compile(r"Creating parent directory:.*")
         out = mock_print.mock_calls[0].__str__()
         assert bool(
             start_pat.search(out)
         ), f"Print statement about directory creation expected. Found: {out}"
-        out_last = mock_print.mock_calls[-1]
-        assert out_last == call(
-            ".svg format not implemented. Writing to .html"
-        ), f"Expected print statement about .svg. Found: {out_last}"
         write_pth = os.path.join(tmpdir, "points2.html")
         assert os.path.exists(
             write_pth