flink-python/pyflink/dataframe/tests/test_context.py

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import unittest
from typing import get_type_hints, Optional

import pyflink.dataframe as pf
from pyflink.table import EnvironmentSettings, TableEnvironment
from pyflink.testing.test_case_utils import PyFlinkUTTestCase


class TableEnvironmentContextValidationTests(unittest.TestCase):
    def test_public_type_hints_are_resolvable(self):
        self.assertEqual(
            get_type_hints(pf.set_table_environment),
            {
                "t_env": Optional[TableEnvironment],
                "return": type(None),
            },
        )
        self.assertEqual(
            get_type_hints(pf.get_table_environment),
            {"return": Optional[TableEnvironment]},
        )
        self.assertEqual(
            get_type_hints(pf.get_or_create_table_environment),
            {"return": TableEnvironment},
        )

    def test_set_environment_rejects_invalid_type_without_changing_state(self):
        previous_environment = pf.get_table_environment()
        self.addCleanup(pf.set_table_environment, previous_environment)

        with self.assertRaisesRegex(
            TypeError, "t_env must be a TableEnvironment or None"
        ):
            pf.set_table_environment(object())

        self.assertIs(pf.get_table_environment(), previous_environment)


class TableEnvironmentContextTests(PyFlinkUTTestCase):
    def setUp(self):
        super().setUp()
        previous_environment = pf.get_table_environment()
        self.addCleanup(pf.set_table_environment, previous_environment)

    def test_set_environment_makes_it_retrievable(self):
        pf.set_table_environment(self.t_env)

        self.assertIs(pf.get_table_environment(), self.t_env)

    def test_set_batch_table_environment_makes_it_retrievable(self):
        batch_environment = TableEnvironment.create(
            EnvironmentSettings.in_batch_mode()
        )

        pf.set_table_environment(batch_environment)

        self.assertIs(pf.get_table_environment(), batch_environment)

    def test_set_none_clears_the_environment(self):
        pf.set_table_environment(self.t_env)

        pf.set_table_environment(None)

        self.assertIsNone(pf.get_table_environment())

    def test_created_environment_is_retrievable(self):
        pf.set_table_environment(None)

        created_environment = pf.get_or_create_table_environment()

        self.assertIs(created_environment, pf.get_table_environment())


if __name__ == "__main__":
    unittest.main()