Enable parameter validation for skl. (#5477)

python-package/xgboost/core.py

@@ -1098,6 +1098,7 @@ class DeviceQuantileDMatrix(DMatrix):
                 ctypes.c_int(self.max_bin), ctypes.byref(handle)))
         self.handle = handle
 
+
 class Booster(object):
     # pylint: disable=too-many-public-methods
     """A Booster of XGBoost.
@@ -1129,10 +1130,12 @@ class Booster(object):
         self.handle = ctypes.c_void_p()
         _check_call(_LIB.XGBoosterCreate(dmats, c_bst_ulong(len(cache)),
                                          ctypes.byref(self.handle)))
+        params = params or {}
+        if isinstance(params, list):
+            params.append(('validate_parameters', True))
+        else:
+            params['validate_parameters'] = True
 
-        if isinstance(params, dict) and \
-            'validate_parameters' not in params.keys():
-            params['validate_parameters'] = 1
         self.set_param(params or {})
         if (params is not None) and ('booster' in params):
             self.booster = params['booster']

python-package/xgboost/sklearn.py

@@ -210,7 +210,7 @@ class XGBModel(XGBModelBase):
                  missing=np.nan, num_parallel_tree=None,
                  monotone_constraints=None, interaction_constraints=None,
                  importance_type="gain", gpu_id=None,
-                 validate_parameters=False, **kwargs):
+                 validate_parameters=None, **kwargs):
         if not SKLEARN_INSTALLED:
             raise XGBoostError(
                 'sklearn needs to be installed in order to use this module')
@@ -242,9 +242,6 @@ class XGBModel(XGBModelBase):
         self.interaction_constraints = interaction_constraints
         self.importance_type = importance_type
         self.gpu_id = gpu_id
-        # Parameter validation is not working with Scikit-Learn interface, as
-        # it passes all paraemters into XGBoost core, whether they are used or
-        # not.
         self.validate_parameters = validate_parameters
 
     def get_booster(self):
@@ -340,9 +337,16 @@ class XGBModel(XGBModelBase):
         return params
 
     def get_xgb_params(self):
-        """Get xgboost type parameters."""
-        xgb_params = self.get_params()
-        return xgb_params
+        """Get xgboost specific parameters."""
+        params = self.get_params()
+        # Parameters that should not go into native learner.
+        wrapper_specific = {
+            'importance_type', 'kwargs', 'missing', 'n_estimators'}
+        filtered = dict()
+        for k, v in params.items():
+            if k not in wrapper_specific:
+                filtered[k] = v
+        return filtered
 
     def get_num_boosting_rounds(self):
         """Gets the number of xgboost boosting rounds."""
@@ -540,7 +544,8 @@ class XGBModel(XGBModelBase):
         if evals_result:
             for val in evals_result.items():
                 evals_result_key = list(val[1].keys())[0]
-                evals_result[val[0]][evals_result_key] = val[1][evals_result_key]
+                evals_result[val[0]][evals_result_key] = val[1][
+                    evals_result_key]
             self.evals_result_ = evals_result
 
         if early_stopping_rounds is not None: