branchcache: add a "pure topological head" fast path
In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.
So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.
The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.
$ hg init rep
$ cd rep
$ mkdir dir
$ touch foo dir/bar
$ hg -v addremove
adding dir/bar
adding foo
$ hg -v commit -m "add 1"
committing files:
dir/bar
foo
committing manifest
committing changelog
committed changeset 0:6f7f953567a2
$ cd dir/
$ touch ../foo_2 bar_2
$ hg -v addremove
adding dir/bar_2
adding foo_2
$ hg -v commit -m "add 2"
committing files:
dir/bar_2
foo_2
committing manifest
committing changelog
committed changeset 1:e65414bf35c5
$ cd ..
$ hg forget foo
$ hg -v addremove
adding foo
$ hg forget foo
$ hg -v addremove nonexistent
nonexistent: $ENOENT$
[1]
$ cd ..
$ hg init subdir
$ cd subdir
$ mkdir dir
$ cd dir
$ touch a.py
$ hg addremove 'glob:*.py'
adding a.py
$ hg forget a.py
$ hg addremove -I 'glob:*.py'
adding a.py
$ hg forget a.py
$ hg addremove
adding dir/a.py
$ cd ..
$ hg init sim
$ cd sim
$ echo a > a
$ echo a >> a
$ echo a >> a
$ echo c > c
$ hg commit -Ama
adding a
adding c
$ mv a b
$ rm c
$ echo d > d
$ hg addremove -n -s 50 # issue 1696
removing a
adding b
removing c
adding d
recording removal of a as rename to b (100% similar)
$ hg addremove -ns 50 --color debug
[ui.addremove.removed ui.status|removing a]
[ui.addremove.added ui.status|adding b]
[ui.addremove.removed ui.status|removing c]
[ui.addremove.added ui.status|adding d]
[ ui.status|recording removal of a as rename to b (100% similar)]
$ hg addremove -s 50
removing a
adding b
removing c
adding d
recording removal of a as rename to b (100% similar)
$ hg commit -mb
$ cp b c
$ hg forget b
$ hg addremove -s 50
adding b
adding c
$ rm c
$ hg ci -A -m "c" nonexistent
nonexistent: $ENOENT$
abort: failed to mark all new/missing files as added/removed
[255]
$ hg st
! c
$ cd ..