test_vector_clock.py

#!/usr/bin/python3

import copy

def test_vector_clock_create():
    assert VectorClock()

def test_vector_clock_value():
    clock = VectorClock()
    assert clock.value("a") == 0

def test_vector_clock_increment_and_value():
    clock = VectorClock()
    clock.increment("a")
    assert clock.value("a") == 1

def test_vector_clock_simple_merge_and_value():
    clock_a = VectorClock()
    clock_a.increment("a")
    assert clock_a.value("a") == 1

    clock_b = VectorClock()
    clock_b.increment("b")
    assert clock_b.value("b") == 1

    clock = clock_a.merge(clock_b)
    assert clock.value("a") == 1
    assert clock.value("b") == 1

def test_vector_clock_complex_merge_and_value():
    clock_a = VectorClock()
    clock_a.increment("a")
    clock_a.increment("a")
    clock_a.increment("b")
    assert clock_a.value("a") == 2
    assert clock_a.value("b") == 1

    clock_b = VectorClock()
    clock_b.increment("a")
    clock_b.increment("b")
    clock_b.increment("c")
    assert clock_b.value("a") == 1
    assert clock_b.value("b") == 1
    assert clock_b.value("c") == 1

    clock = clock_a.merge(clock_b)
    assert clock.value("a") == 2
    assert clock.value("b") == 1
    assert clock.value("c") == 1

def test_vector_clock_complex_descends_value():
    clock_a = VectorClock()
    clock_a.increment("a")
    clock_a.increment("a")
    clock_a.increment("b")
    assert clock_a.value("a") == 2
    assert clock_a.value("b") == 1

    clock_b = VectorClock()
    clock_b.increment("a")
    clock_b.increment("b")
    clock_b.increment("c")
    assert clock_b.value("a") == 1
    assert clock_b.value("b") == 1
    assert clock_b.value("c") == 1

    clock = clock_a.merge(clock_b)
    assert clock.value("a") == 2
    assert clock.value("b") == 1
    assert clock.value("c") == 1

    assert not clock.happens_before(clock_a)
    assert not clock.happens_before(clock_b)

    assert clock_a.happens_before(clock)
    assert clock_b.happens_before(clock)

    assert not clock.happens_before(clock)

    new_clock_a = copy.deepcopy(clock)
    new_clock_a.increment("a")
    assert clock_a.happens_before(new_clock_a)

    assert clock_b.happens_before(clock)
    assert clock_b.happens_before(new_clock_a)

    assert not clock_b.happens_before(clock_a)
    assert not clock_a.happens_before(clock_b)

def test_vector_clock_complex_concurrent_value():
    clock_a = VectorClock()
    clock_a.increment("a")
    clock_a.increment("a")
    clock_a.increment("b")
    assert clock_a.value("a") == 2
    assert clock_a.value("b") == 1

    clock_b = VectorClock()
    clock_b.increment("a")
    clock_b.increment("b")
    clock_b.increment("c")
    assert clock_b.value("a") == 1
    assert clock_b.value("b") == 1
    assert clock_b.value("c") == 1

    clock = clock_a.merge(clock_b)
    assert clock.value("a") == 2
    assert clock.value("b") == 1
    assert clock.value("c") == 1

    assert not clock.is_concurrent_with(clock_a)
    assert not clock.is_concurrent_with(clock_b)

    assert clock_a.is_concurrent_with(clock_b)
    assert clock.is_concurrent_with(clock)