rust: less set lookups in AncestorsIterator
This uses the boolean return of `HashSet::insert()` to factor
pairs of contains()/insert() into a single insert()
On the mozilla-central repository (450k changesets), I get about a bit more
than 10% better medians in perfancestors (taking the mean of three runs)
Best run for parent changeset:
! wall 0.106474 comb 0.110000 user 0.110000 sys 0.000000 (median of 93)
Best run for this changeset:
! wall 0.093191 comb 0.090000 user 0.090000 sys 0.000000 (median of 100)
Differential Revision: https://phab.mercurial-scm.org/D5942
#!/usr/bin/env python
#
# A portable replacement for 'seq'
#
# Usage:
# seq STOP [1, STOP] stepping by 1
# seq START STOP [START, STOP] stepping by 1
# seq START STEP STOP [START, STOP] stepping by STEP
from __future__ import absolute_import, print_function
import os
import sys
try:
import msvcrt
msvcrt.setmode(sys.stdin.fileno(), os.O_BINARY)
msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
msvcrt.setmode(sys.stderr.fileno(), os.O_BINARY)
except ImportError:
pass
if sys.version_info[0] >= 3:
xrange = range
start = 1
if len(sys.argv) > 2:
start = int(sys.argv[1])
step = 1
if len(sys.argv) > 3:
step = int(sys.argv[2])
stop = int(sys.argv[-1]) + 1
for i in xrange(start, stop, step):
print(i)