tests/test-rust-revlog.py

revlog: have an explicit "pack_header" method

Having to pass the version header when retrieving the binary version of every
single entry is a bit silly. So we extract that special logic in its own method.
This also prepare the move to newer revlog format, not storing the header within
an actual entry…

Differential Revision: https://phab.mercurial-scm.org/D10510

from __future__ import absolute_import
import unittest

try:
    from mercurial import rustext

    rustext.__name__  # trigger immediate actual import
except ImportError:
    rustext = None
else:
    from mercurial.rustext import revlog

    # this would fail already without appropriate ancestor.__package__
    from mercurial.rustext.ancestor import LazyAncestors

from mercurial.testing import revlog as revlogtesting


@unittest.skipIf(
    rustext is None,
    "rustext module revlog relies on is not available",
)
class RustRevlogIndexTest(revlogtesting.RevlogBasedTestBase):
    def test_heads(self):
        idx = self.parseindex()
        rustidx = revlog.MixedIndex(idx)
        self.assertEqual(rustidx.headrevs(), idx.headrevs())

    def test_get_cindex(self):
        # drop me once we no longer need the method for shortest node
        idx = self.parseindex()
        rustidx = revlog.MixedIndex(idx)
        cidx = rustidx.get_cindex()
        self.assertTrue(idx is cidx)

    def test_len(self):
        idx = self.parseindex()
        rustidx = revlog.MixedIndex(idx)
        self.assertEqual(len(rustidx), len(idx))

    def test_ancestors(self):
        idx = self.parseindex()
        rustidx = revlog.MixedIndex(idx)
        lazy = LazyAncestors(rustidx, [3], 0, True)
        # we have two more references to the index:
        # - in its inner iterator for __contains__ and __bool__
        # - in the LazyAncestors instance itself (to spawn new iterators)
        self.assertTrue(2 in lazy)
        self.assertTrue(bool(lazy))
        self.assertEqual(list(lazy), [3, 2, 1, 0])
        # a second time to validate that we spawn new iterators
        self.assertEqual(list(lazy), [3, 2, 1, 0])

        # let's check bool for an empty one
        self.assertFalse(LazyAncestors(idx, [0], 0, False))


if __name__ == '__main__':
    import silenttestrunner

    silenttestrunner.main(__name__)