Merge pull request #311 from lvgig/292-bug-capping-transformer-get_pa…

…rams-method-error

🐛 fixed bug with get_params method when capping_values=None

CHANGELOG.rst

@@ -38,6 +38,7 @@ Changed
 - Refactored DateDifferenceTransformer tests in new format. Had to turn off autodefine new_column_name functionality to match generic test expectations. Suggest we look to turn back on in the future. `#296 https://github.com/lvgig/tubular/issues/296`
 - Refactored DateDiffLeapYearTransformer tests in new format. As part of this had to remove the autodefined new_column_name, as this conflicts with the generic testing. Suggest we look to turn back on in future. `#295 https://github.com/lvgig/tubular/issues/295`
 - Edited base testing setup for dates file, created new BaseDatetimeTransformer class
+- fixed a bug in CappingTransformer which was preventing use of .get_params method `#311 <https://github.com/lvgig/tubular/issues/311>`_
 
 
 1.3.1 (2024-07-18)

tests/capping/test_CappingTransformer.py

@@ -126,3 +126,20 @@ class TestOtherBaseBehaviour(OtherBaseBehaviourTests):
     @classmethod
     def setup_class(cls):
         cls.transformer_name = "CappingTransformer"
+
+    def test_get_params_call_with_capping_values_none(
+        self,
+        uninitialized_transformers,
+        minimal_attribute_dict,
+    ):
+        """Test get_params method when capping_values is None."""
+        args = minimal_attribute_dict[self.transformer_name]
+        args["capping_values"] = None
+        args["quantiles"] = {"a": [0.1, 0.9]}
+        transformer = uninitialized_transformers[self.transformer_name](**args)
+
+        # Ensure no AttributeError is raised when calling get_params method
+        try:
+            transformer.get_params()
+        except AttributeError as e:
+            pytest.fail(f"AttributeError was raised: {e}")

tubular/capping.py

@@ -80,8 +80,6 @@ def __init__(
         if capping_values is not None:
             self.check_capping_values_dict(capping_values, "capping_values")
 
-            self.capping_values = capping_values
-
             super().__init__(columns=list(capping_values.keys()), **kwargs)
 
         if quantiles is not None:
@@ -98,6 +96,7 @@ def __init__(
             super().__init__(columns=list(quantiles.keys()), **kwargs)
 
         self.quantiles = quantiles
+        self.capping_values = capping_values
         WeightColumnMixin.check_and_set_weight(self, weights_column)
 
     def check_capping_values_dict(