"""Tests for the configiration related utility functions."""

import pytest

from snowflake_etl.conf.config import merge_configs


@pytest.mark.parametrize('c1,c2,expected', [
    (dict(a=1, b=2), dict(c=3), dict(a=1, b=2, c=3)),
    (dict(a=1, b=2), dict(b=3), dict(a=1, b=3)),
    (dict(a=1), dict(), dict(a=1)),
    (dict(), dict(b=3), dict(b=3)),
    (dict(), dict(), dict()),
    (dict(a=1), dict(a=None), dict(a=1)),
    (dict(a=1, b=2, c=3), dict(a=1, b=2, c=3), dict(a=1, b=2, c=3)),
    (dict(a=1, b=2, c=3), dict(a=2, b=3, c=4), dict(a=2, b=3, c=4)),
])
def test_merge_configs(c1, c2, expected):
    """Test merge_configs function."""
    result = merge_configs(c1, c2)

    assert result == expected
    # the function is supposed to instantiate a new dict
    assert result is not c1
    assert result is not c2