Change revlog.heads to walk the revision graph using revision numbers
On the kernel repo:
$ hg heads -q
before after
RevlogNG 1.11 0.52
Revlogv0 0.80 0.69
Since the current code for tags has to find all the heads of the repo,
this also helps there:
$ hg tags
before after
RevlogNG 2.35 1.76
Revlogv0 2.04 1.90
#!/bin/sh
#
mkdir t
cd t
hg init
echo 0 > a
echo 0 > b
hg ci -A -m m -d "1000000 0"
hg rm a
hg cat a
sleep 1 # make sure mtime is changed
echo 1 > b
hg ci -m m -d "1000000 0"
echo 2 > b
hg cat -r 0 a
hg cat -r 0 b
hg cat -r 1 a
hg cat -r 1 b