tests/test-annotate.py

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.

import unittest

from mercurial import (
    mdiff,
    pycompat,
)
from mercurial.dagop import (
    annotateline,
    _annotatedfile,
    _annotatepair,
)


def tr(a):
    return [
        annotateline(fctx, lineno, skip)
        for fctx, lineno, skip in zip(a.fctxs, a.linenos, a.skips)
    ]


class AnnotateTests(unittest.TestCase):
    """Unit tests for annotate code."""

    def testannotatepair(self):
        self.maxDiff = None  # camelcase-required

        oldfctx = b'old'
        p1fctx, p2fctx, childfctx = b'p1', b'p2', b'c'
        olddata = b'a\nb\n'
        p1data = b'a\nb\nc\n'
        p2data = b'a\nc\nd\n'
        childdata = b'a\nb2\nc\nc2\nd\n'
        diffopts = mdiff.diffopts()

        def decorate(text, fctx):
            n = text.count(b'\n')
            linenos = pycompat.rangelist(1, n + 1)
            return _annotatedfile([fctx] * n, linenos, [False] * n, text)

        # Basic usage

        oldann = decorate(olddata, oldfctx)
        p1ann = decorate(p1data, p1fctx)
        p1ann = _annotatepair([oldann], p1fctx, p1ann, False, diffopts)
        self.assertEqual(
            tr(p1ann),
            [
                annotateline(b'old', 1),
                annotateline(b'old', 2),
                annotateline(b'p1', 3),
            ],
        )

        p2ann = decorate(p2data, p2fctx)
        p2ann = _annotatepair([oldann], p2fctx, p2ann, False, diffopts)
        self.assertEqual(
            tr(p2ann),
            [
                annotateline(b'old', 1),
                annotateline(b'p2', 2),
                annotateline(b'p2', 3),
            ],
        )

        # Test with multiple parents (note the difference caused by ordering)

        childann = decorate(childdata, childfctx)
        childann = _annotatepair(
            [p1ann, p2ann], childfctx, childann, False, diffopts
        )
        self.assertEqual(
            tr(childann),
            [
                annotateline(b'old', 1),
                annotateline(b'c', 2),
                annotateline(b'p2', 2),
                annotateline(b'c', 4),
                annotateline(b'p2', 3),
            ],
        )

        childann = decorate(childdata, childfctx)
        childann = _annotatepair(
            [p2ann, p1ann], childfctx, childann, False, diffopts
        )
        self.assertEqual(
            tr(childann),
            [
                annotateline(b'old', 1),
                annotateline(b'c', 2),
                annotateline(b'p1', 3),
                annotateline(b'c', 4),
                annotateline(b'p2', 3),
            ],
        )

        # Test with skipchild (note the difference caused by ordering)

        childann = decorate(childdata, childfctx)
        childann = _annotatepair(
            [p1ann, p2ann], childfctx, childann, True, diffopts
        )
        self.assertEqual(
            tr(childann),
            [
                annotateline(b'old', 1),
                annotateline(b'old', 2, True),
                # note that this line was carried over from earlier so it is *not*
                # marked skipped
                annotateline(b'p2', 2),
                annotateline(b'p2', 2, True),
                annotateline(b'p2', 3),
            ],
        )

        childann = decorate(childdata, childfctx)
        childann = _annotatepair(
            [p2ann, p1ann], childfctx, childann, True, diffopts
        )
        self.assertEqual(
            tr(childann),
            [
                annotateline(b'old', 1),
                annotateline(b'old', 2, True),
                annotateline(b'p1', 3),
                annotateline(b'p1', 3, True),
                annotateline(b'p2', 3),
            ],
        )


if __name__ == '__main__':
    import silenttestrunner

    silenttestrunner.main(__name__)