Add : new raise value error and linked unit test

Author: BaptisteCalot

mapie/tests/test_regression.py

@@ -985,6 +985,27 @@ def test_using_one_predict_parameter_into_predict_but_not_in_fit() -> None:
         mapie_fitted.predict(X_test, **predict_params)
 
 
+def test_using_one_predict_parameter_into_fit_but_not_in_predict() -> None:
+    """Test that using predict parameters in the fit method
+    without using one predict_parameter in
+    the predict method raises an error"""
+    custom_gbr = CustomGradientBoostingRegressor(random_state=random_state)
+    X_train, X_test, y_train, y_test = (
+        train_test_split(X, y, test_size=0.2, random_state=random_state)
+    )
+    mapie = MapieRegressor(estimator=custom_gbr)
+    predict_params = {'check_predict_params': True}
+    mapie_fitted = mapie.fit(X_train, y_train, predict_params=predict_params)
+
+    with pytest.raises(ValueError, match=(
+        r"Using one 'predict_param' in the fit method "
+        r"without using one 'predict_param' in the predict method. "
+        r"Please ensure one 'predict_param' "
+        r"is used in the predict method before calling it."
+    )):
+        mapie_fitted.predict(X_test)
+
+
 def test_predict_infinite_intervals() -> None:
     """Test that MapieRegressor produces infinite bounds with alpha=0"""
     mapie_reg = MapieRegressor().fit(X, y)

mapie/utils.py

@@ -1398,12 +1398,18 @@ def check_predict_params(
         If any predict_params are used in the predict method but none
         are used in the fit method.
     """
-    if (len(predict_params) > 0 and
-            predict_params_used_in_fit is False and
-            cv != "prefit"):
-        raise ValueError(
-            f"Using 'predict_param' '{predict_params}' "
-            f"without using one 'predict_param' in the fit method. "
-            f"Please ensure one 'predict_param' "
-            f"is used in the fit method before calling predict."
-        )
+    if cv != "prefit":
+        if len(predict_params) > 0 and predict_params_used_in_fit is False:
+            raise ValueError(
+                f"Using 'predict_param' '{predict_params}' "
+                f"without using one 'predict_param' in the fit method. "
+                f"Please ensure one 'predict_param' "
+                f"is used in the fit method before calling predict."
+            )
+        if len(predict_params) == 0 and predict_params_used_in_fit is True:
+            raise ValueError(
+                "Using one 'predict_param' in the fit method "
+                "without using one 'predict_param' in the predict method. "
+                "Please ensure one 'predict_param' "
+                "is used in the predict method before calling it."
+            )