def test_xirr():
assert ff.xirr([-100, 20, 40, 25], [
date(2016, 1, 1),
date(2016, 4, 1),
date(2016, 10, 1),
date(2017, 2, 1)
]) == -0.19674386129832788
assert ff.xirr([-100, 20, 40, 25, 8, 15], [
date(2016, 1, 1),
date(2016, 4, 1),
date(2016, 10, 1),
date(2017, 2, 1),
date(2017, 3, 1),
date(2017, 6, 1)
]) == 0.0944390744445201
assert ff.xirr([-1000, 300, 400, 400, 300], [
date(2011, 12, 1),
date(2012, 1, 1),
date(2013, 2, 1),
date(2014, 3, 1),
date(2015, 4, 1)
], 0.1) == 0.23860325587217
def test_xirr_dates_not_chronological_order():
with pytest.raises(ValueError):
ff.xirr([-100, 20], [date(2016, 4, 1), date(2016, 1, 1)])
def test_xirr_mismatched_lists():
with pytest.raises(ValueError):
ff.xirr([-100], [])