[MRG+1] Regressor chain tags (#13337)

amueller · GaelVaroquaux · commit bf6949ba9d5f · 2019-03-01T12:29:57.000+01:00
* don't skip chain estimator in common tests

* fix fitted check in chain estimators

* actually still skip on classifier chain
diff --git a/sklearn/multioutput.py b/sklearn/multioutput.py
@@ -460,6 +460,7 @@ def predict(self, X):
             The predicted values.
 
         """
+        check_is_fitted(self, 'estimators_')
         X = check_array(X, accept_sparse=True)
         Y_pred_chain = np.zeros((X.shape[0], len(self.estimators_)))
         for chain_idx, estimator in enumerate(self.estimators_):
@@ -636,7 +637,8 @@ def decision_function(self, X):
         return Y_decision
 
     def _more_tags(self):
-        return {'_skip_test': True}
+        return {'_skip_test': True,
+                'multioutput_only': True}
 
 
 class RegressorChain(_BaseChain, RegressorMixin, MetaEstimatorMixin):
@@ -722,5 +724,4 @@ def fit(self, X, Y):
         return self
 
     def _more_tags(self):
-        # FIXME
-        return {'_skip_test': True}
+        return {'multioutput_only': True}
