phases: avoid N² behavior in `advanceboundary` We allowed duplicated entries in the deque, which each entry could potentially insert all its ancestors. So advancing boundary for the full repository would mean each revision would walk all its ancestors, resulting in O(N²) iteration. For repository of any decent size, N² is quickly insane. We introduce a simple set to avoid this and get back to reasonable performance.

#!/usr/bin/env python3
#
# A tool to help producing large and poorly compressible files
#
# Usage:
#   $TESTDIR/seq.py 1000 | $TESTDIR/sha256line.py > my-file.txt


import hashlib
import sys


for line in sys.stdin:
    print(hashlib.sha256(line.encode('utf8')).hexdigest())