cext-revlog: fixed __delitem__ for uninitialized nodetree
This is a bug in a code path that's seldom used, because in practice
(at least in the whole test suite), calls to `del index[i:j]` currently
just don't happen before the nodetree has been initialized.
However, in our current work to replace the nodetree by a Rust implementation,
this is of course systematic.
In `index_slice_del()`, if the slice start is smaller than `self->length`,
the whole of `self->added` has to be cleared.
Before this change, the clearing was done only by the call to
`index_invalidate_added(self, 0)`, that happens only for initialized
nodetrees. Hence the removal was effective only from `start` to `self->length`.
The consequence is index corruption, with bogus results in subsequent calls,
and in particular errors such as `ValueError("parent out of range")`, due to
the fact that parents of entries in `self->added` are now just invalid.
This is detected by the rebase tests, under conditions that the nodetree
of revlog.c is never initialized. The provided specific test is more direct.
Differential Revision: https://phab.mercurial-scm.org/D7603
#require unix-permissions no-root
initial setup
$ cat << EOF >> $HGRCPATH
> [ui]
> ssh="$PYTHON" "$TESTDIR/dummyssh"
> EOF
repository itself is non-readable
---------------------------------
$ hg init no-read
$ hg id ssh://user@dummy/no-read
000000000000
$ chmod a-rx no-read
$ hg id ssh://user@dummy/no-read
remote: abort: Permission denied: *$TESTTMP/no-read/.hg* (glob)
abort: no suitable response from remote hg!
[255]
special case files are visible, but unreadable
----------------------------------------------
This is "similar" to the test above, but the directory is "traversable". This
seems an unexpected case in real life, but we test it anyway.
$ hg init other
$ hg id ssh://user@dummy/other
000000000000
$ for item in `find other | sort -r` ; do
> chmod a-r $item
> done
$ hg id ssh://user@dummy/other
remote: abort: Permission denied: '$TESTTMP/other/.hg/requires'
abort: no suitable response from remote hg!
[255]
directory toward the repository is read only
--------------------------------------------
$ mkdir deep
$ hg init deep/nested
$ hg id ssh://user@dummy/deep/nested
000000000000
$ chmod a-rx deep
$ hg id ssh://user@dummy/deep/nested
remote: abort: Permission denied: *$TESTTMP/deep/nested/.hg* (glob)
abort: no suitable response from remote hg!
[255]
repository has wrong requirement
--------------------------------
$ hg init repo-future
$ hg id ssh://user@dummy/repo-future
000000000000
$ echo flying-car >> repo-future/.hg/requires
$ hg id ssh://user@dummy/repo-future
remote: abort: repository requires features unknown to this Mercurial: flying-car!
remote: (see https://mercurial-scm.org/wiki/MissingRequirement for more information)
abort: no suitable response from remote hg!
[255]