Improve test coverage for generate_model.py to 100% (adapted for developing branch)

tests/example_structure/configurations/configuration_no_transform.yml

@@ -0,0 +1,9 @@
+overrides:
+envelope_structure: Envelope structure
+envelopes:
+  My envelope name 1: { filler: Model 1 }
+  Envelope_2: { filler: Model 2 }
+source: Main source
+tallies: [fine_mesh]
+materials: [Standard materials]
+transforms: [My transform]

tests/example_structure/project_summary.csv

@@ -1,16 +1,16 @@
 Name,Relative path,Description
-fine_mesh,data_cards\fine_mesh.tally,
-My transform,data_cards\my_transform.transform,
-Ring source,data_cards\ring_source.source,
-Main source,data_cards\volumetric_source.source,
-Wrong data card,data_cards\wrong_data_card.mat,
-Materials BAD,data_cards\materials_bad_library.mat,
-Standard materials,data_cards\materials.mat,
-Wrong suffix,data_cards\wrong_suffix.wrong,
-Model 1,models\filler_model_1.mcnp,
-Model 2,models\filler_model_2.mcnp,
-Envelope structure,models\main_input.mcnp,
-Model 3,models\path_to_be_excluded\filler_model_3.mcnp,
-Bad model 1,models\path_to_be_excluded\only_cells_block.mcnp,
-Bad model 2,models\path_to_be_excluded\wrong_surfaces_block.mcnp,
-Standard configuration,configurations\configuration_1.yml,
+fine_mesh,data_cards/fine_mesh.tally,
+My transform,data_cards/my_transform.transform,
+Ring source,data_cards/ring_source.source,
+Main source,data_cards/volumetric_source.source,
+Wrong data card,data_cards/wrong_data_card.mat,
+Materials BAD,data_cards/materials_bad_library.mat,
+Standard materials,data_cards/materials.mat,
+Wrong suffix,data_cards/wrong_suffix.wrong,
+Model 1,models/filler_model_1.mcnp,
+Model 2,models/filler_model_2.mcnp,
+Envelope structure,models/main_input.mcnp,
+Model 3,models/path_to_be_excluded/filler_model_3.mcnp,
+Bad model 1,models/path_to_be_excluded/only_cells_block.mcnp,
+Bad model 2,models/path_to_be_excluded/wrong_surfaces_block.mcnp,
+Standard configuration,configurations/configuration_1.yml,

tests/test_generate_model.py

@@ -1,8 +1,9 @@
 from pathlib import Path
+from unittest.mock import patch, mock_open
 
 import pytest
 
-from gitronics.generate_model import generate_model
+from gitronics.generate_model import generate_model, _get_envelope_structure_first_cell_id
 
 ROOT_FOLDER_PATH = Path(__file__).resolve().parents[1] / "tests" / "example_structure"
 PROJECT_SUMMARY_PATH = (
@@ -79,3 +80,83 @@ def test_envelope_name_not_found_in_envelope_structure(tmpdir):
             project_summary_path=PROJECT_SUMMARY_PATH,
             write_path=Path(tmpdir),
         )
+
+
+def test_envelope_with_transform_branch(tmpdir):
+    """Test case to ensure the transform branch is properly covered.
+    This tests the if envelope_data.transform branch on line 84-85."""
+    configuration_path = (
+        Path(__file__).resolve().parents[1]
+        / "tests"
+        / "example_structure"
+        / "configurations/configuration_1.yml"
+    )
+    generate_model(
+        root_folder_path=ROOT_FOLDER_PATH,
+        configuration_file_path=configuration_path,
+        project_summary_path=PROJECT_SUMMARY_PATH,
+        write_path=Path(tmpdir),
+    )
+
+    # Verify the transform was included in the output
+    with open(tmpdir / "assembled.mcnp") as infile:
+        result_text = infile.read()
+
+    # Check that the transform "(1)" was included in the FILL card for Envelope_2
+    # From the configuration: Envelope_2: { filler: Model 2, transform: (1) }
+    # Model 2 has universe ID u=125
+    assert " FILL = 125  (1) " in result_text
+    assert "$ Envelope_2" in result_text
+
+
+def test_get_envelope_structure_first_cell_id_no_match():
+    """Test the exception case in _get_envelope_structure_first_cell_id 
+    when no line starts with a digit."""
+    from gitronics.model_manager import ModelManager
+
+    # Create a minimal configuration and project that will work
+    configuration_path = (
+        Path(__file__).resolve().parents[1]
+        / "tests"
+        / "example_structure"
+        / "configurations/configuration_1.yml"
+    )
+
+    model_manager = ModelManager(
+        root_folder_path=ROOT_FOLDER_PATH,
+        configuration_file_path=configuration_path,
+        project_summary_path=PROJECT_SUMMARY_PATH,
+    )
+
+    # Mock the file content to have no lines starting with digits
+    mock_file_content = "Title\nC Comment line\nC Another comment\n   Some indented text\n"
+
+    with patch("builtins.open", mock_open(read_data=mock_file_content)):
+        with pytest.raises(ValueError, match="Could not find the first cell ID"):
+            _get_envelope_structure_first_cell_id(model_manager)
+
+
+def test_envelope_without_transform_branch(tmpdir):
+    """Test case to ensure the no-transform branch is properly covered.
+    This tests the else branch when envelope_data.transform is None/empty."""
+    configuration_path = (
+        Path(__file__).resolve().parents[1]
+        / "tests"
+        / "example_structure"
+        / "configurations/configuration_no_transform.yml"
+    )
+    generate_model(
+        root_folder_path=ROOT_FOLDER_PATH,
+        configuration_file_path=configuration_path,
+        project_summary_path=PROJECT_SUMMARY_PATH,
+        write_path=Path(tmpdir),
+    )
+
+    # Verify the transform was NOT included in the output for Envelope_2
+    with open(tmpdir / "assembled.mcnp") as infile:
+        result_text = infile.read()
+
+    # Check that there's no transform in the FILL card for Envelope_2
+    # Should be "FILL = 125 " without any transform
+    assert " FILL = 125 \n           $ Envelope_2" in result_text
+    assert "$ Envelope_2" in result_text