"""
Tests for calculator operations.

NOTE: Test coverage is intentionally incomplete for testing purposes.
"""
import pytest

from calculator.operations import add, subtract, multiply


class TestAdd:
    """Tests for add operation."""

    def test_add_positive_numbers(self):
        assert add(2, 3) == 5

    def test_add_negative_numbers(self):
        assert add(-2, -3) == -5

    # MISSING: test_add_zero, test_add_floats


class TestSubtract:
    """Tests for subtract operation."""

    def test_subtract_positive(self):
        assert subtract(5, 3) == 2

    # MISSING: test_subtract_negative, test_subtract_resulting_negative


class TestMultiply:
    """Tests for multiply operation."""

    def test_multiply_positive(self):
        assert multiply(3, 4) == 12

    # MISSING: test_multiply_by_zero, test_multiply_negative


# MISSING: TestDivide class entirely!
# - test_divide_positive
# - test_divide_by_zero (should test error handling)
# - test_divide_negative

# MISSING: TestPower class entirely!