def test_single_history():
doc = Document('http://example.com', 'Example')
history = History([doc])
assert history.is_at_most_recent
assert history.is_at_oldest
assert history.current == doc
assert list(history.get_items()) == [(True, doc)]
assert load_history(dump_history(history)) == history
with pytest.raises(ValueError):
history.back()
with pytest.raises(ValueError):
history.forward()
# Adding same document does not change history.
new_doc = Document('http://example.com', 'Example')
new_history = history.add(new_doc)
assert list(new_history.get_items()) == [(True, doc)]
# Adding same URL, different title changes existing item.
new_doc = Document('http://example.com', 'New')
new_history = history.add(new_doc)
assert list(new_history.get_items()) == [(True, new_doc)]
# Adding different document changes history.
new_doc = Document('http://other.com', 'Example')
new_history = history.add(new_doc)
assert list(new_history.get_items()) == [(True, new_doc), (False, doc)]
def test_empty_history():
history = History()
assert history.is_at_most_recent
assert history.is_at_oldest
assert history.current is None
assert list(history.get_items()) == []
assert load_history(dump_history(history)) == history
with pytest.raises(ValueError):
history.back()
with pytest.raises(ValueError):
history.forward()
# Adding new document changes history.
new_doc = Document('http://example.com', 'Example')
new_history = history.add(new_doc)
assert list(new_history.get_items()) == [(True, new_doc)]
