tests/test-annotate.py

dirstate-tree: Add tree traversal/iteration

Like Python’s, Rust’s iterators are "external" in that they are driven
by a caller who calls a `next` method. This is as opposed to "internal"
iterators who drive themselves and call a callback for each item.

Writing an internal iterator traversing a tree is easy with recursion,
but internal iterators cannot rely on the call stack in that way,
they must save in an explicit object all state that they need to be
preserved across two `next` calls.

This algorithm uses a `Vec` as a stack that contains what would be
local variables on the call stack if we could use recursion.

Differential Revision: https://phab.mercurial-scm.org/D10370

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__)