view tests/test-annotate.py @ 48671:f1ed5c304f45

encoding: fix trim() to be O(n) instead of O(n^2)

`encoding.trim()` iterated over the possible lengths smaller than the
input and created a slice for each. It then calculated the column
width of the result, which is of course O(n), so the overall algorithm
was O(n). This patch rewrites it to iterate over the unicode
characters, keeping track of the length so far. Also, the old
algorithm started from the end of the string, which made it much worse
when the input is large and the limit is small (such as the typical 72
we pass to it).

You can time it by running something like this:

```
time python3 -c 'from mercurial.utils import stringutil; print(stringutil.ellipsis(b"0123456789" * 1000, 5))'
```

That drops from 4.05 s to 83 ms with this patch (and most of that is
of course startup time).

Differential Revision: https://phab.mercurial-scm.org/D12089

from __future__ import absolute_import
from __future__ import print_function

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__)