def test_two_particles_like_signs():
pos1 = DummyParticle(+1)
pos2 = DummyParticle(+1)
particles = [pos1, pos2]
pairs = find_pairs(particles)
assert_equal(len(pairs), 0)
def test_no_particles():
particles = []
pairs = find_pairs(particles)
assert len(pairs) == 0 #assert means if condition isnt true, test fails
def test_two_particles_unlike_sign():
pos = DummyParticle(+1)
neg = DummyParticle(-1)
particles = [pos,neg]
pairs = find_pairs(particles)
assert_list_equal(pairs,[(pos,neg)])
def test_one_particle():
particles = [None]
pairs = find_pairs(particles)
assert len(pairs) == 0
def test_no_particles():
particles = []
pairs = find_pairs(particles)
assert len(pairs) == 0
def test_one_particles():
pos = DummyParticle(+1)
particles = [pos]
pairs = find_pairs(particles)
assert len(pairs) == 0
