$ branches=.hg/branchheads.cache
$ echo '[extensions]' >> $HGRCPATH
$ echo 'mq =' >> $HGRCPATH
$ show_branch_cache()
> {
> # force cache (re)generation
> hg log -r does-not-exist 2> /dev/null
> hg log -r tip --template 'tip: {rev}\n'
> if [ -f $branches ]; then
> sort $branches
> else
> echo No branch cache
> fi
> if [ "$1" = 1 ]; then
> for b in foo bar; do
> hg log -r $b --template "branch $b: "'{rev}\n'
> done
> fi
> }
$ hg init a
$ cd a
$ hg qinit -c
mq patch on an empty repo
$ hg qnew p1
$ show_branch_cache
tip: 0
No branch cache
$ echo > pfile
$ hg add pfile
$ hg qrefresh -m 'patch 1'
$ show_branch_cache
tip: 0
No branch cache
some regular revisions
$ hg qpop
popping p1
patch queue now empty
$ echo foo > foo
$ hg add foo
$ echo foo > .hg/branch
$ hg ci -m 'branch foo' -d '1000000 0'
$ echo bar > bar
$ hg add bar
$ echo bar > .hg/branch
$ hg ci -m 'branch bar' -d '1000000 0'
$ show_branch_cache
tip: 1
3f910abad313ff802d3a23a7529433872df9b3ae 1
3f910abad313ff802d3a23a7529433872df9b3ae bar
9539f35bdc80732cc9a3f84e46508f1ed1ec8cff foo
add some mq patches
$ hg qpush
applying p1
now at: p1
$ show_branch_cache
tip: 2
3f910abad313ff802d3a23a7529433872df9b3ae 1
3f910abad313ff802d3a23a7529433872df9b3ae bar
9539f35bdc80732cc9a3f84e46508f1ed1ec8cff foo
$ hg qnew p2
$ echo foo > .hg/branch
$ echo foo2 >> foo
$ hg qrefresh -m 'patch 2'
$ show_branch_cache 1
tip: 3
3f910abad313ff802d3a23a7529433872df9b3ae 1
3f910abad313ff802d3a23a7529433872df9b3ae bar
9539f35bdc80732cc9a3f84e46508f1ed1ec8cff foo
branch foo: 3
branch bar: 2
removing the cache
$ rm $branches
$ show_branch_cache 1
tip: 3
3f910abad313ff802d3a23a7529433872df9b3ae 1
3f910abad313ff802d3a23a7529433872df9b3ae bar
9539f35bdc80732cc9a3f84e46508f1ed1ec8cff foo
branch foo: 3
branch bar: 2
importing rev 1 (the cache now ends in one of the patches)
$ hg qimport -r 1 -n p0
$ show_branch_cache 1
tip: 3
3f910abad313ff802d3a23a7529433872df9b3ae 1
3f910abad313ff802d3a23a7529433872df9b3ae bar
9539f35bdc80732cc9a3f84e46508f1ed1ec8cff foo
branch foo: 3
branch bar: 2
$ hg log -r qbase --template 'qbase: {rev}\n'
qbase: 1
detect an invalid cache
$ hg qpop -a
popping p2
popping p1
popping p0
patch queue now empty
$ hg qpush -a
applying p0
applying p1
applying p2
now at: p2
$ show_branch_cache
tip: 3
9539f35bdc80732cc9a3f84e46508f1ed1ec8cff 0
9539f35bdc80732cc9a3f84e46508f1ed1ec8cff foo