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# to you under the Apache License, Version 2.0 (the
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#
#   http://www.apache.org/licenses/LICENSE-2.0
#
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import pytest
from pytest_mock import MockerFixture


def test_epoch_to_dttm() -> None:
    """
    Test the `epoch_to_dttm` method.
    """
    from superset.db_engine_specs.db2 import Db2EngineSpec

    assert (
        Db2EngineSpec.epoch_to_dttm().format(col="epoch_dttm")
        == "(TIMESTAMP('1970-01-01', '00:00:00') + epoch_dttm SECONDS)"
    )


def test_get_table_comment(mocker: MockerFixture):
    """
    Test the `get_table_comment` method.
    """
    from superset.db_engine_specs.db2 import Db2EngineSpec

    mock_inspector = mocker.MagicMock()
    mock_inspector.get_table_comment.return_value = {
        "text": ("This is a table comment",)
    }

    assert (
        Db2EngineSpec.get_table_comment(mock_inspector, "my_table", "my_schema")
        == "This is a table comment"
    )


def test_get_table_comment_empty(mocker: MockerFixture):
    """
    Test the `get_table_comment` method
    when no comment is returned.
    """
    from superset.db_engine_specs.db2 import Db2EngineSpec

    mock_inspector = mocker.MagicMock()
    mock_inspector.get_table_comment.return_value = {}

    assert (
        Db2EngineSpec.get_table_comment(mock_inspector, "my_table", "my_schema") == None
    )


def test_get_prequeries() -> None:
    """
    Test the ``get_prequeries`` method.
    """
    from superset.db_engine_specs.db2 import Db2EngineSpec

    assert Db2EngineSpec.get_prequeries() == []
    assert Db2EngineSpec.get_prequeries(schema="my_schema") == [
        'set current_schema "my_schema"'
    ]