revlog: fix revlogio.packentry corner case
We want to store version information about the revlog in the first
entry of its index. The code in packentry was using some heuristics
to detect whether this was the first entry, but these heuristics could
fail in some cases (e.g. rev 0 was empty; rev 1 descends directly from
the nullid and is stored as a delta).
We now give the revision number to packentry to avoid heuristics.
#!/bin/sh
# In the merge below, the file "foo" has the same contents in both
# parents, but if we look at the file-level history, we'll notice that
# the version in p1 is an ancestor of the version in p2. This test
# makes sure that we'll use the version from p2 in the manifest of the
# merge revision.
hg init repo
cd repo
echo foo > foo
hg ci -d '0 0' -qAm 'add foo'
echo bar >> foo
hg ci -d '0 0' -m 'change foo'
hg backout -d '0 0' -r tip -m 'backout changed foo'
hg up -C 0
touch bar
hg ci -d '0 0' -qAm 'add bar'
hg merge --debug
hg debugstate | grep foo
hg st -A foo
hg ci -d '0 0' -m 'merge'
hg manifest --debug | grep foo
hg debugindex .hg/store/data/foo.i