#
# Licensed to the Apache Software Foundation (ASF) under one or more
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# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
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import unittest

from pyspark.ml.linalg import Vectors
from pyspark.ml.stat import ChiSquareTest
from pyspark.sql import DataFrame
from pyspark.testing.mlutils import SparkSessionTestCase


class ChiSquareTestTests(SparkSessionTestCase):

    def test_chisquaretest(self):
        data = [[0, Vectors.dense([0, 1, 2])],
                [1, Vectors.dense([1, 1, 1])],
                [2, Vectors.dense([2, 1, 0])]]
        df = self.spark.createDataFrame(data, ['label', 'feat'])
        res = ChiSquareTest.test(df, 'feat', 'label')
        # This line is hitting the collect bug described in #17218, commented for now.
        # pValues = res.select("degreesOfFreedom").collect())
        self.assertIsInstance(res, DataFrame)
        fieldNames = set(field.name for field in res.schema.fields)
        expectedFields = ["pValues", "degreesOfFreedom", "statistics"]
        self.assertTrue(all(field in fieldNames for field in expectedFields))


if __name__ == "__main__":
    from pyspark.ml.tests.test_stat import *

    try:
        import xmlrunner
        testRunner = xmlrunner.XMLTestRunner(output='target/test-reports')
    except ImportError:
        testRunner = None
    unittest.main(testRunner=testRunner, verbosity=2)