def test_shared_times_bounds_time_idx_inputs(self):
        """
        Tests that `get_shared_times_bounds` behaves correctly
        when passed `pd.Index` inputs instead of `TimeSeries`
        inputs. Mixtures of `pd.Index` and `TimeSeries` inputs
        are also checked.
        """
        # Defined so `series_1` starts and ends before `series_2` does:
        series_1 = linear_timeseries(start=0, end=10, freq=1)
        series_2 = linear_timeseries(start=2, end=16, freq=2)
        expected_bounds = (series_2.start_time(), series_1.end_time())
        # Pass only `series_1.time_index` - bounds are just start and
        # end times of this series:
        assert get_shared_times_bounds(series_1.time_index) == (
            series_1.start_time(),
            series_1.end_time(),
        )
        # Pass only `series_2.time_index` - bounds are just start and
        # end times of this series:
        assert get_shared_times_bounds(series_2.time_index) == (
            series_2.start_time(),
            series_2.end_time(),
        )
        assert get_shared_times_bounds(series_1.time_index, series_2) == expected_bounds
        assert get_shared_times_bounds(series_1, series_2.time_index) == expected_bounds
        assert (
            get_shared_times_bounds(series_1.time_index, series_2.time_index)
            == expected_bounds
        )

        Tests that `get_shared_times_bounds` behaves correctly
        when passed `pd.Index` inputs instead of `TimeSeries`
        inputs. Mixtures of `pd.Index` and `TimeSeries` inputs
        are also checked.
        
darts/tests/utils/tabularization/test_get_shared_times_bounds.py