def test_upgrades_from_existing_format_to_target_format(self):
storage = storage_with_format("1.0")
upgrader = Upgrader(target="2.0", steps={"1.0": mock_upgrade_to("2.0")})
upgrader.upgrade(storage)
assert_that(format_of(storage), equal_to("2.0"))
def test_raises_error_if_no_upgrader_from_current_version(self):
storage = storage_with_format("1.0")
upgrader = Upgrader(target="4.0", steps={"2.0": never_called, "3.0": never_called})
try:
upgrader.upgrade(storage)
raise AssertionError("should have raised an exception")
except UserError as e:
assert_that(str(e), contains_string("cannot migrate from version 1.0 to version 4.0"))
def test_raises_error_if_run_against_version_higher_than_target(self):
storage = storage_with_format("3.0")
upgrader = Upgrader(target="2.0", steps={"1.0": never_called, "2.0": never_called})
try:
upgrader.upgrade(storage)
raise AssertionError("should have raised an exception")
except UserError as e:
assert_that(str(e), contains_string("cannot migrate from version 3.0 to version 2.0"))
def test_does_not_have_to_start_from_lowest_version(self):
storage = storage_with_format("2.0")
upgrader = Upgrader(
target="4.0",
steps={"1.0": mock_upgrade_to("2.0"), "2.0": mock_upgrade_to("3.0"), "3.0": mock_upgrade_to("4.0")},
)
upgrader.upgrade(storage)
assert_that(format_of(storage), equal_to("4.0"))
def test_applies_multiple_upgrade_steps_until_format_is_same_as_target(self):
storage = storage_with_format("1.0")
upgrader = Upgrader(
target="4.0",
steps={"1.0": mock_upgrade_to("2.0"), "2.0": mock_upgrade_to("3.0"), "3.0": mock_upgrade_to("4.0")},
)
upgrader.upgrade(storage)
assert_that(format_of(storage), equal_to("4.0"))
def test_returns_false_if_already_at_target_version(self):
storage = storage_with_format("2.0")
upgrader = Upgrader(target="2.0", steps={"1.0": never_called})
assert_that(upgrader.upgrade(storage), equal_to(False))
def test_returns_true_if_has_performed_upgrade_actions(self):
storage = storage_with_format("1.0")
upgrader = Upgrader(target="2.0", steps={"1.0": mock_upgrade_to("2.0")})
assert_that(upgrader.upgrade(storage), equal_to(True))
