Refactor

There's an opportunity to add a method to our class that will make our testing code just a bit nicer to work with.

class Clumper():
    def __init__(self, blob):
        self.blob = blob

    def __len__(self):
        return len(self.blob)

    ...

This will allow us to refactor this test:

def test_headtail_size():
    data = [{'i': i} for i in range(10)]
    c = Clumper(data)
    assert len(c.head(10).collect()) == 10
    assert len(c.tail(10).collect()) == 10
    assert len(c.head(5).collect()) == 5
    assert len(c.tail(5).collect()) == 5

Into this test:

def test_headtail_size():
    data = [{'i': i} for i in range(10)]
    c = Clumper(data)
    assert len(c.head(10)) == 10
    assert len(c.tail(10)) == 10
    assert len(c.head(5)) == 5
    assert len(c.tail(5)) == 5

This is a whole lot better. But we're not done yet!