LGTM

pipeline/transform/test_crime.py

@@ -44,4 +44,76 @@ def test_transform_crime_reads_only_street_crime_csvs(tmp_path):
 
     result = pl.read_parquet(output).to_dicts()
 
-    assert result == [{"LSOA code": "E01000001", "Burglary (avg/yr)": 2.0}]
+    assert result == [{"LSOA code": "E01000001", "Burglary (avg/yr)": 24.0}]
+
+
+def test_transform_crime_annualises_over_all_valid_months(tmp_path):
+    crime_dir = tmp_path / "crime"
+    jan_dir = crime_dir / "2024-01"
+    feb_dir = crime_dir / "2024-02"
+    jan_dir.mkdir(parents=True)
+    feb_dir.mkdir(parents=True)
+
+    header = "Crime ID,Month,Reported by,Falls within,Longitude,Latitude,Location,LSOA code,LSOA name,Crime type,Last outcome category,Context"
+    (jan_dir / "2024-01-test-force-street.csv").write_text(
+        "\n".join(
+            [
+                header,
+                "1,2024-01,Test Force,Test Force,-0.1,51.5,On or near Test Street,E01000001,Test LSOA,Burglary,Under investigation,",
+                "2,2024-01,Test Force,Test Force,-0.1,51.5,On or near Test Street,E01000001,Test LSOA,Burglary,Under investigation,",
+                "3,2024-01,Test Force,Test Force,-0.1,51.5,On or near Test Street,E01000002,Other LSOA,Robbery,Under investigation,",
+            ]
+        )
+        + "\n"
+    )
+    (feb_dir / "2024-02-test-force-street.csv").write_text(
+        "\n".join(
+            [
+                header,
+                "4,2024-02,Test Force,Test Force,-0.1,51.5,On or near Test Street,E01000002,Other LSOA,Robbery,Under investigation,",
+            ]
+        )
+        + "\n"
+    )
+
+    output = tmp_path / "crime.parquet"
+    transform_crime(crime_dir, output)
+
+    result = pl.read_parquet(output).sort("LSOA code").to_dicts()
+
+    assert result == [
+        {
+            "LSOA code": "E01000001",
+            "Burglary (avg/yr)": 12.0,
+            "Robbery (avg/yr)": 0.0,
+        },
+        {
+            "LSOA code": "E01000002",
+            "Burglary (avg/yr)": 0.0,
+            "Robbery (avg/yr)": 12.0,
+        },
+    ]
+
+
+def test_transform_crime_fails_without_valid_months(tmp_path):
+    crime_dir = tmp_path / "crime"
+    month_dir = crime_dir / "2024-01"
+    month_dir.mkdir(parents=True)
+    (month_dir / "2024-01-test-force-street.csv").write_text(
+        "\n".join(
+            [
+                "Crime ID,Month,Reported by,Falls within,Longitude,Latitude,Location,LSOA code,LSOA name,Crime type,Last outcome category,Context",
+                "1,,Test Force,Test Force,-0.1,51.5,On or near Test Street,E01000001,Test LSOA,Burglary,Under investigation,",
+            ]
+        )
+        + "\n"
+    )
+
+    output = tmp_path / "crime.parquet"
+
+    try:
+        transform_crime(crime_dir, output)
+    except ValueError as exc:
+        assert "No valid crime months" in str(exc)
+    else:
+        raise AssertionError("Expected ValueError")