Playing around with Hypothesis package for property-based testing in Python

test_selection_sort_with_hypothesis.py

import functools

from hypothesis import given, strategies as st


def selection_sort(items):
    items = list(items)
    for idx, _ in enumerate(items, 0):
        min_idx = idx
        for jdx, item in enumerate(items[idx+1:], idx+1):
            if item < items[min_idx]:
                min_idx = jdx
        items[idx], items[min_idx] = items[min_idx], items[idx]
    return items


@given(st.lists(st.integers()).filter(lambda items: len(items) > 1))
def test_selection_sort(items):
    sorted_items = selection_sort(items)
    assert functools.reduce(
        lambda P, Q: P and Q,
        [sorted_items[idx-1] <= sorted_items[idx] for idx in range(1, len(sorted_items))]
    )