view tests/test-lrucachedict.py @ 35023:3649c3f2cd90

revert: do not reverse hunks in interactive when REV is not parent (issue5096)

And introduce a new "apply" operation verb for this case as suggested in
issue5096. This replaces the no longer used "revert" operation.

In interactive revert, when reverting to something else that the parent
revision, display an "apply this change" message with a diff that is not
reversed.

The rationale is that `hg revert -i -r REV` will show hunks of the diff from
the working directory to REV and prompt the user to select them for applying
(to working directory). This contradicts dcc56e10c23b in which it was
decided to have the "direction" of prompted hunks reversed. Later on
[1], there was a broad consensus (but no decision) towards the "as to
be applied direction". Now that --interactive is no longer experimental
(5910db5d1913), it's time to switch and thus we drop no longer used
"experimental.revertalternateinteractivemode" configuration option.

[1]: https://www.mercurial-scm.org/pipermail/mercurial-devel/2016-November/090142.html


.. feature::

  When interactive revert is run against a revision other than the working
  directory parent, the diff shown is the diff to *apply* to the working directory,
  rather than the diff to *discard* from the working copy. This is in line with
  related user experiences with `git` and appears to be less confusing with
  `ui.interface=curses`.

from __future__ import absolute_import, print_function

from mercurial import (
    util,
)

def printifpresent(d, xs, name='d'):
    for x in xs:
        present = x in d
        print("'%s' in %s: %s" % (x, name, present))
        if present:
            print("%s['%s']: %s" % (name, x, d[x]))

def test_lrucachedict():
    d = util.lrucachedict(4)
    d['a'] = 'va'
    d['b'] = 'vb'
    d['c'] = 'vc'
    d['d'] = 'vd'

    # all of these should be present
    printifpresent(d, ['a', 'b', 'c', 'd'])

    # 'a' should be dropped because it was least recently used
    d['e'] = 've'
    printifpresent(d, ['a', 'b', 'c', 'd', 'e'])

    assert d.get('a') is None
    assert d.get('e') == 've'

    # touch entries in some order (get or set).
    d['e']
    d['c'] = 'vc2'
    d['d']
    d['b'] = 'vb2'

    # 'e' should be dropped now
    d['f'] = 'vf'
    printifpresent(d, ['b', 'c', 'd', 'e', 'f'])

    d.clear()
    printifpresent(d, ['b', 'c', 'd', 'e', 'f'])

    # Now test dicts that aren't full.
    d = util.lrucachedict(4)
    d['a'] = 1
    d['b'] = 2
    d['a']
    d['b']
    printifpresent(d, ['a', 'b'])

    # test copy method
    d = util.lrucachedict(4)
    d['a'] = 'va3'
    d['b'] = 'vb3'
    d['c'] = 'vc3'
    d['d'] = 'vd3'

    dc = d.copy()

    # all of these should be present
    print("\nAll of these should be present:")
    printifpresent(dc, ['a', 'b', 'c', 'd'], 'dc')

    # 'a' should be dropped because it was least recently used
    print("\nAll of these except 'a' should be present:")
    dc['e'] = 've3'
    printifpresent(dc, ['a', 'b', 'c', 'd', 'e'], 'dc')

    # contents and order of original dict should remain unchanged
    print("\nThese should be in reverse alphabetical order and read 'v?3':")
    dc['b'] = 'vb3_new'
    for k in list(iter(d)):
        print("d['%s']: %s" % (k, d[k]))

if __name__ == '__main__':
    test_lrucachedict()