obshashrange: warm the cache at the end of each transaction
This will help having warmed cache for read only client.
The warming is still imperfect in case of markers that trigger a reset, but we
are in a better place than what we used to be.
#require test-repo pyflakes
Copied from Mercurial core (60ee2593a270)
$ cd "`dirname "$TESTDIR"`"
run pyflakes on all tracked files ending in .py or without a file ending
(skipping binary file random-seed)
$ hg locate 'set:(**.py or grep("^#!.*python")) - removed()' 2>/dev/null \
> | xargs pyflakes 2>/dev/null