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.
#require no-windows no-rhg
XXX-RHG this test hangs if `hg` is really `rhg`. This was hidden by the use of
`alias hg=rhg` by run-tests.py. With such alias removed, this test is revealed
buggy. This need to be resolved sooner than later.
Dummy extension simulating unsafe long running command
$ SYNC_FILE="$TESTTMP/sync-file"
$ export SYNC_FILE
$ DONE_FILE="$TESTTMP/done-file"
$ export DONE_FILE
$
$ cat > wait_ext.py <<EOF
> import os
> import time
>
> from mercurial.i18n import _
> from mercurial import registrar
> from mercurial import testing
>
> cmdtable = {}
> command = registrar.command(cmdtable)
>
> @command(b'wait-signal', [], _(b'SYNC_FILE DONE_FILE'), norepo=True)
> def sleep(ui, sync_file=b"$SYNC_FILE", done_file=b"$DONE_FILE", **opts):
> start = time.time()
> with ui.uninterruptible():
> testing.write_file(sync_file, b'%d' % os.getpid())
> testing.wait_file(done_file)
> ui.warn(b"end of unsafe operation\n")
> ui.warn(b"%d second(s) passed\n" % int(time.time() - start))
> EOF
$ cat > send-signal.sh << EOF
> #!/bin/sh
> SIG=\$1
> if [ -z "\$SIG" ]; then
> echo "send-signal.sh requires one argument" >&2
> exit 1
> fi
> "$RUNTESTDIR/testlib/wait-on-file" 10 "$SYNC_FILE" || exit 2
> kill -s \$SIG \`cat "$SYNC_FILE"\`
> EOF
#if no-windows
$ chmod +x send-signal.sh
#endif
$ cat > wait-signal.sh << 'EOF'
> #!/bin/sh
> (hg wait-signal 2>&1; echo [$?]) | {
> read line
> touch "$DONE_FILE"
> echo "$line"
> cat
> }
> EOF
#if no-windows
$ chmod +x wait-signal.sh
#endif
Kludge to emulate timeout(1) which is not generally available.
Set up repository
$ hg init repo
$ cd repo
$ cat >> $HGRCPATH << EOF
> [extensions]
> wait_ext = $TESTTMP/wait_ext.py
> EOF
Test ctrl-c
$ rm -f $SYNC_FILE $DONE_FILE
$ sh -c "../send-signal.sh INT" &
$ ../wait-signal.sh
interrupted!
[255]
$ cat >> $HGRCPATH << EOF
> [experimental]
> nointerrupt = yes
> EOF
$ rm -f $SYNC_FILE $DONE_FILE
$ sh -c "../send-signal.sh INT" &
$ ../wait-signal.sh
interrupted!
[255]
$ cat >> $HGRCPATH << EOF
> [experimental]
> nointerrupt-interactiveonly = False
> EOF
$ rm -f $SYNC_FILE $DONE_FILE
$ sh -c "../send-signal.sh INT" &
$ ../wait-signal.sh
shutting down cleanly
press ^C again to terminate immediately (dangerous)
end of unsafe operation
interrupted!
[255]