Raise an error if y is not None

bob/pipelines/wrappers.py

@@ -153,6 +153,12 @@ class SampleWrapper(BaseWrapper, TransformerMixin):
         return self._samples_transform(samples, "score")
 
     def fit(self, samples, y=None):
+        if y is not None:
+            raise TypeError(
+                "We don't accept `y` in fit arguments because "
+                "`y` should be part of the sample. To pass `y` "
+                "to the wrapped estimator, use `fit_extra_arguments`."
+            )
 
         if is_estimator_stateless(self.estimator):
             return self