Change type of warning

Author: Guillaume Lemaitre

imblearn/base.py

@@ -86,8 +86,7 @@ def fit(self, X, y):
         #     raise RuntimeError("Only one class detected, aborting...")
         # Raise a warning for the moment to be compatible with BaseEstimator
         if np.unique(y).size == 1:
-            warnings.warn('Only one class detected, something will get wrong',
-                          RuntimeWarning)
+            warnings.warn('Only one class detected, something will get wrong')
 
         # Store the size of X to check at sampling time if we have the
         # same data

imblearn/combine/tests/test_smote_enn.py

@@ -78,7 +78,7 @@ def test_smote_fit_single_class():
     # Resample the data
     # Create a wrong y
     y_single_class = np.zeros((X.shape[0], ))
-    assert_warns(RuntimeWarning, smote.fit, X, y_single_class)
+    assert_warns(UserWarning, smote.fit, X, y_single_class)
 
 
 def test_smote_fit():