test_export.py 文件源码

def test_graphviz_errors():
    # Check for errors of export_graphviz
    clf = DecisionTreeClassifier(max_depth=3, min_samples_split=2)
    clf.fit(X, y)

    # Check feature_names error
    out = StringIO()
    assert_raises(IndexError, export_graphviz, clf, out, feature_names=[])

    # Check class_names error
    out = StringIO()
    assert_raises(IndexError, export_graphviz, clf, out, class_names=[])