shelve: restore shelved dirstate explicitly after aborting transaction
Before this patch, "hg shelve" uses aborting a current transaction to
discard temporary changes while shelving.
This assumes that dirstate changes in a transaction scope are kept
even after aborting it. But this assumption will be broken by
"transactional dirstate". See the wiki page below for detail about it.
https://mercurial.selenic.com/wiki/DirstateTransactionPlan
This patch explicitly saves shelved dirstate just before aborting
current transaction, and restore dirstate with it after aborting by
utility function '_aborttransaction()' added by previous patch.
This patch replaces 'if tr: tr.abort()' by 'lockmod.release(tr)',
because the former is already done in '_aborttransaction()' (and the
latter has no effect), if current transaction is aborted in it
successfully. Otherwise, the latter is enough to trigger aborting.
# showstack.py - extension to dump a Python stack trace on signal
#
# binds to both SIGQUIT (Ctrl-\) and SIGINFO (Ctrl-T on BSDs)
import sys, signal, traceback
def sigshow(*args):
sys.stderr.write("\n")
traceback.print_stack(args[1], limit=10, file=sys.stderr)
sys.stderr.write("----\n")
def extsetup(ui):
signal.signal(signal.SIGQUIT, sigshow)
try:
signal.signal(signal.SIGINFO, sigshow)
except AttributeError:
pass