Mercurial > hg
view tests/test-rust-ancestor.py @ 51239:7eea2e4109ae
rust-index: using the `hg::index::Index` in ancestors iterator and lazy set
Since there is no Rust implementation for REVLOGV2/CHANGELOGv2, we declare
them to be incompatible with Rust, hence indexes in these formats will use
the implementations from Python `mercurial.ancestor`. If this is an unacceptable
performance hit for current users of these formats, we can later on add Rust
implementations based on the C index for them or implement these formats for
the Rust indexes.
Among the challenges that we had to meet, we wanted to avoid taking the GIL each
time the inner (vcsgraph) iterator has to call the parents function. This would probably
still be acceptable in terms of performance with `AncestorsIterator`, but not with
`LazyAncestors` nor for the upcoming change in `MissingAncestors`.
Hence we enclose the reference to the index in a `PySharedRef`, leading to more
rigourous checking of mutations, which does pass now that there no logically immutable
methods of `hg::index::Index` that take a mutable reference as input.
author | Georges Racinet <georges.racinet@octobus.net> |
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date | Fri, 27 Oct 2023 22:11:05 +0200 |
parents | 4c5f6e95df84 |
children | 59d81768ad6d |
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import sys import unittest from mercurial.node import wdirrev from mercurial.testing import revlog as revlogtesting try: from mercurial import rustext rustext.__name__ # trigger immediate actual import except ImportError: rustext = None else: # this would fail already without appropriate ancestor.__package__ from mercurial.rustext.ancestor import ( AncestorsIterator, LazyAncestors, MissingAncestors, ) from mercurial.rustext import dagop try: from mercurial.cext import parsers as cparsers except ImportError: cparsers = None @unittest.skipIf( rustext is None, 'The Rust version of the "ancestor" module is not available. It is needed' ' for this test.', ) @unittest.skipIf( rustext is None, 'The Rust or C version of the "parsers" module, which the "ancestor" module' ' relies on, is not available.', ) class rustancestorstest(revlogtesting.RevlogBasedTestBase): """Test the correctness of binding to Rust code. This test is merely for the binding to Rust itself: extraction of Python variable, giving back the results etc. It is not meant to test the algorithmic correctness of the operations on ancestors it provides. Hence the very simple embedded index data is good enough. Algorithmic correctness is asserted by the Rust unit tests. """ def testiteratorrevlist(self): idx = self.parserustindex() # checking test assumption about the index binary data: self.assertEqual( {i: (r[5], r[6]) for i, r in enumerate(idx)}, {0: (-1, -1), 1: (0, -1), 2: (1, -1), 3: (2, -1)}, ) ait = AncestorsIterator(idx, [3], 0, True) self.assertEqual([r for r in ait], [3, 2, 1, 0]) ait = AncestorsIterator(idx, [3], 0, False) self.assertEqual([r for r in ait], [2, 1, 0]) def testlazyancestors(self): idx = self.parserustindex() start_count = sys.getrefcount(idx) # should be 2 (see Python doc) self.assertEqual( {i: (r[5], r[6]) for i, r in enumerate(idx)}, {0: (-1, -1), 1: (0, -1), 2: (1, -1), 3: (2, -1)}, ) lazy = LazyAncestors(idx, [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.assertEqual(sys.getrefcount(idx), start_count + 2) 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]) # now let's watch the refcounts closer ait = iter(lazy) self.assertEqual(sys.getrefcount(idx), start_count + 3) del ait self.assertEqual(sys.getrefcount(idx), start_count + 2) del lazy self.assertEqual(sys.getrefcount(idx), start_count) # let's check bool for an empty one self.assertFalse(LazyAncestors(idx, [0], 0, False)) def testmissingancestors(self): idx = self.parseindex() missanc = MissingAncestors(idx, [1]) self.assertTrue(missanc.hasbases()) self.assertEqual(missanc.missingancestors([3]), [2, 3]) missanc.addbases({2}) self.assertEqual(missanc.bases(), {1, 2}) self.assertEqual(missanc.missingancestors([3]), [3]) self.assertEqual(missanc.basesheads(), {2}) def testmissingancestorsremove(self): idx = self.parseindex() missanc = MissingAncestors(idx, [1]) revs = {0, 1, 2, 3} missanc.removeancestorsfrom(revs) self.assertEqual(revs, {2, 3}) def testrefcount(self): idx = self.parserustindex() start_count = sys.getrefcount(idx) # refcount increases upon iterator init... ait = AncestorsIterator(idx, [3], 0, True) self.assertEqual(sys.getrefcount(idx), start_count + 1) self.assertEqual(next(ait), 3) # and decreases once the iterator is removed del ait self.assertEqual(sys.getrefcount(idx), start_count) # and removing ref to the index after iterator init is no issue ait = AncestorsIterator(idx, [3], 0, True) del idx self.assertEqual(list(ait), [3, 2, 1, 0]) # the index is not tracked by the GC, hence there is nothing more # we can assert to check that it is properly deleted once its refcount # drops to 0 def testgrapherror(self): data = ( revlogtesting.data_non_inlined[: 64 + 27] + b'\xf2' + revlogtesting.data_non_inlined[64 + 28 :] ) idx = self.parserustindex(data=data) with self.assertRaises(rustext.GraphError) as arc: AncestorsIterator(idx, [1], -1, False) exc = arc.exception self.assertIsInstance(exc, ValueError) # rust-cpython issues appropriate str instances for Python 2 and 3 self.assertEqual(exc.args, ('ParentOutOfRange', 1)) def testwdirunsupported(self): # trying to access ancestors of the working directory raises idx = self.parserustindex() with self.assertRaises(rustext.GraphError) as arc: list(AncestorsIterator(idx, [wdirrev], -1, False)) exc = arc.exception self.assertIsInstance(exc, ValueError) # rust-cpython issues appropriate str instances for Python 2 and 3 self.assertEqual(exc.args, ('InvalidRevision', wdirrev)) def testheadrevs(self): idx = self.parseindex() self.assertEqual(dagop.headrevs(idx, [1, 2, 3]), {3}) if __name__ == '__main__': import silenttestrunner silenttestrunner.main(__name__)