Refactor: Organize unit tests and add pipeline_utils tests

Moved existing unit test files from:
- tests/unit/data_ingestion/
- tests/unit/data_preprocessing/

To:
- tests/unit/model/data_ingestion/
- tests/unit/model/data_preprocessing/

Additionally, created new unit tests for pipeline_utils under:
- tests/unit/model/pipeline_utils/

Author: anibalrojosan

…it/data_ingestion/test_data_ingestion.py …el/data_ingestion/test_data_ingestion.pytests/unit/data_ingestion/test_data_ingestion.py renamed to tests/unit/model/data_ingestion/test_data_ingestion.py tests/unit/data_ingestion/test_data_ingestion.py renamed to tests/unit/model/data_ingestion/test_data_ingestion.py

@@ -0,0 +1,48 @@
+from sklearn.pipeline import Pipeline
+from sklearn.preprocessing import FunctionTransformer
+from sklearn.preprocessing import MinMaxScaler
+from sklearn.ensemble import RandomForestClassifier
+
+from src.model.pipeline_utils import create_breast_cancer_pipeline
+from src.model.data_preprocessing import drop_unnecessary_columns
+
+def test_create_breast_cancer_pipeline_returns_pipeline():
+    """Test that the create_breast_cancer_pipeline function returns a Pipeline object."""
+    pipeline = create_breast_cancer_pipeline()
+    assert isinstance(pipeline, Pipeline)
+
+def test_create_breast_cancer_pipeline_has_correct_top_level_steps():
+    """Test that pipeline has the expected steps (preprocessor and classifier)."""
+    pipeline = create_breast_cancer_pipeline()
+    assert len(pipeline.steps) == 2
+    assert pipeline.steps[0][0] == 'preprocessor'
+    assert pipeline.steps[1][0] == 'classifier'
+
+def test_create_breast_cancer_pipeline_has_correct_preprocessor_steps():
+    """Test that pipeline has the expected 'preprocessor' steps (drop_cols and scaler)."""
+    pipeline = create_breast_cancer_pipeline()
+    preprocessor = pipeline.named_steps['preprocessor']
+    assert isinstance(preprocessor, Pipeline)
+    assert len(preprocessor.steps) == 2
+    assert preprocessor.steps[0][0] == 'drop_cols'
+    assert preprocessor.steps[1][0] == 'scaler'
+
+def test_drop_cols_configuration():
+    """Test that the 'drop_cols' step is configured correctly."""
+    pipeline = create_breast_cancer_pipeline()
+    drop_cols_transformer = pipeline.named_steps['preprocessor'].named_steps['drop_cols']
+    assert drop_cols_transformer.func == drop_unnecessary_columns
+    assert drop_cols_transformer.validate == False
+
+def test_scaler_configuration():
+    """Test that the 'scaler' step is configured correctly (MinMaxScaler)."""
+    pipeline = create_breast_cancer_pipeline()
+    scaler_transformer = pipeline.named_steps['preprocessor'].named_steps['scaler']
+    assert isinstance(scaler_transformer, MinMaxScaler)
+
+def test_classifier_estimator_configuration():
+    """Test that the 'classifier' is a RandomForestClassifier with random_state=42."""
+    pipeline = create_breast_cancer_pipeline()
+    classifier_estimator = pipeline.named_steps['classifier']
+    assert isinstance(classifier_estimator, RandomForestClassifier)
+    assert classifier_estimator.random_state == 42