revlog: add a magic null revision to our index
We expand our index by one entry so that index[nullrev] points to a
unique entry, the null revision. This naturally eliminates numerous
extra tests in the performance-sensitive index access functions, most
of which are now trivial again.
Adding new entries is now done with insert(-1, e) rather than
append(e).
# strutil.py - string utilities for Mercurial
#
# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.
def findall(haystack, needle, start=0, end=None):
if end is None:
end = len(haystack)
if end < 0:
end += len(haystack)
if start < 0:
start += len(haystack)
while start < end:
c = haystack.find(needle, start, end)
if c == -1:
break
yield c
start = c + 1
def rfindall(haystack, needle, start=0, end=None):
if end is None:
end = len(haystack)
if end < 0:
end += len(haystack)
if start < 0:
start += len(haystack)
while end >= 0:
c = haystack.rfind(needle, start, end)
if c == -1:
break
yield c
end = c - 1