Feature/unit test for validations

test/test_file_validator/test_forms.py

+"""Tests for the file_validator forms."""
+import csv
+import io
+from unittest.mock import MagicMock
+
+from django.core.files.uploadedfile import SimpleUploadedFile
+
+from sage_validation.file_validator.forms import CSVUploadForm
+
+
+def create_modified_csv(sample_file: SimpleUploadedFile, modifications: dict[str, str]) -> SimpleUploadedFile:
+    """
+    Modify specific fields in the first row of a CSV file and return a new SimpleUploadedFile.
+
+    Args:
+        sample_file (SimpleUploadedFile): The original CSV file.
+        modifications (dict): Dictionary of column names to modified values.
+
+    Returns:
+        SimpleUploadedFile: The modified CSV file.
+    """
+    csv_content = sample_file.read().decode("utf-8").splitlines()
+    reader = csv.DictReader(csv_content)
+    rows = list(reader)
+
+    for key, value in modifications.items():
+        rows[0][key] = value
+
+    output = io.StringIO()
+    writer = csv.DictWriter(output, fieldnames=reader.fieldnames or [])
+    writer.writeheader()
+    writer.writerows(rows)
+
+    return SimpleUploadedFile("test_modified.csv", output.getvalue().encode("utf-8"), content_type="text/csv")
+
+
+def test_valid_csv_upload(sample_input_file: SimpleUploadedFile, mock_meo_database: MagicMock) -> None:
+    """Test CSV upload with valid data."""
+    form = CSVUploadForm(files={"file": sample_input_file})
+    assert form.is_valid(), f"Form errors: {form.errors}"
+
+
+def test_invalid_file_extension() -> None:
+    """Test form rejects non-CSV files."""
+    bad_file = SimpleUploadedFile("test.txt", b"Some text content", content_type="text/plain")
+    form = CSVUploadForm(files={"file": bad_file})
+    assert not form.is_valid()
+    assert "File must be in CSV format." in form.errors["file"]
+
+
+def test_missing_required_columns() -> None:
+    """Test form rejects CSV missing required headers."""
+    invalid_csv = SimpleUploadedFile("test.csv", b"AccountNumber,CBAccountNumber\n12345,54321", content_type="text/csv")
+    form = CSVUploadForm(files={"file": invalid_csv})
+    assert not form.is_valid()
+    assert "Missing required columns" in str(form.errors)
+
+
+def test_source_and_trader_type_validation(sample_input_file: SimpleUploadedFile, mock_meo_database: MagicMock) -> None:
+    """Test validation for Source and SYSTraderTranType columns."""
+    modified_file = create_modified_csv(sample_input_file, {"Source": "90", "SYSTraderTranType": "5"})
+    form = CSVUploadForm(files={"file": modified_file})
+    assert not form.is_valid()
+    assert "Row 1: 'Source' must be 80" in form.errors["file"][0]
+    assert "Row 1: 'SYSTraderTranType' must be 4" in form.errors["file"][1]
+
+
+def test_validate_nominal_analysis_account(sample_input_file: SimpleUploadedFile, mock_meo_database: MagicMock) -> None:
+    """Test validation for nominal analysis account."""
+    modified_file = create_modified_csv(sample_input_file,
+                                        {"NominalAnalysisNominalAnalysisNarrative/1": "Invalid Name"})
+    form = CSVUploadForm(files={"file": modified_file})
+    assert not form.is_valid()
+    assert form.errors["file"][0] == (
+        "Row 1: 'AccountNumber' must match 'Sample Narrative' in 'NominalAnalysisNominalAnalysisNarrative/1'"
+        ", but found 'Invalid Name'.")
+
+
+def test_validate_nc_cc_dep_combination_against_meo_sage_account(
+        sample_input_file: SimpleUploadedFile, mock_meo_database: MagicMock
+) -> None:
+    """Test validation for nominal analysis fields against MEO valid Sage accounts."""
+    modified_file = create_modified_csv(
+        sample_input_file,
+        {
+            "NominalAnalysisNominalCostCentre/1": "Invalid_CC",
+            "NominalAnalysisNominalAccountNumber/1": "Invalid_Account"
+        })
+
+    form = CSVUploadForm(files={"file": modified_file})
+    assert not form.is_valid()
+    assert ("Row 1: 'NominalAnalysisNominalCostCentre/1' (Invalid_CC) is not a valid cost centre."
+            in str(form.errors["file"][0]))
+