TST Fix estimator checks for classifers with poor_score tag (#16851)

thomasjpfan · web-flow · commit 692899d172c4 · 2020-06-27T10:56:15.000+02:00
diff --git a/sklearn/utils/estimator_checks.py b/sklearn/utils/estimator_checks.py
@@ -2349,7 +2349,8 @@ def check_class_weight_classifiers(name, classifier_orig):
         y_pred = classifier.predict(X_test)
         # XXX: Generally can use 0.89 here. On Windows, LinearSVC gets
         #      0.88 (Issue #9111)
-        assert np.mean(y_pred == 0) > 0.87
+        if not classifier_orig._get_tags()['poor_score']:
+            assert np.mean(y_pred == 0) > 0.87
 
 
 @ignore_warnings(category=FutureWarning)
diff --git a/sklearn/utils/tests/test_estimator_checks.py b/sklearn/utils/tests/test_estimator_checks.py
@@ -334,6 +334,14 @@ def _more_tags(self):
         return {"requires_positive_y": True}
 
 
+class PoorScoreLogisticRegression(LogisticRegression):
+    def decision_function(self, X):
+        return super().decision_function(X) + 1
+
+    def _more_tags(self):
+        return {"poor_score": True}
+
+
 def test_not_an_array_array_function():
     if np_version < parse_version('1.17'):
         raise SkipTest("array_function protocol not supported in numpy <1.17")
@@ -462,6 +470,9 @@ def test_check_estimator():
     assert_raises_regex(ValueError, msg, check_estimator,
                         RequiresPositiveYRegressor())
 
+    # Does not raise error on classifier with poor_score tag
+    check_estimator(PoorScoreLogisticRegression())
+
 
 def test_check_outlier_corruption():
     # should raise AssertionError
