Mercurial > hg
view mercurial/ancestor.py @ 6858:8f256bf98219
Add support for multiple possible bisect results (issue1228, issue1182)
The real reason for both issue is that bisect can not handle cases where there
are multiple possibilities for the result.
Example (from issue1228):
rev 0 -> good
rev 1 -> skipped
rev 2 -> skipped
rev 3 -> skipped
rev 4 -> bad
Note that this patch does not only fix the reported Assertion Error but also
the problem of a non converging bisect:
hg init
for i in `seq 3`; do echo $i > $i; hg add $i; hg ci -m$i; done
hg bisect -b 2
hg bisect -g 0
hg bisect -s
From this state on, you can:
a) mark as bad forever (non converging!)
b) mark as good to get an inconsistent state
c) skip for the Assertion Error
Minor description and code edits by pmezard.
author | Bernhard Leiner <bleiner@gmail.com> |
---|---|
date | Sat, 02 Aug 2008 22:10:10 +0200 |
parents | 532ca442b903 |
children | 8d78fc991b71 |
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# ancestor.py - generic DAG ancestor algorithm for mercurial # # Copyright 2006 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms # of the GNU General Public License, incorporated herein by reference. import heapq def ancestor(a, b, pfunc): """ return the least common ancestor of nodes a and b or None if there is no such ancestor. pfunc must return a list of parent vertices """ if a == b: return a # find depth from root of all ancestors visit = [a, b] depth = {} while visit: vertex = visit[-1] pl = pfunc(vertex) if not pl: depth[vertex] = 0 visit.pop() else: for p in pl: if p == a or p == b: # did we find a or b as a parent? return p # we're done if p not in depth: visit.append(p) if visit[-1] == vertex: depth[vertex] = min([depth[p] for p in pl]) - 1 visit.pop() # traverse ancestors in order of decreasing distance from root def ancestors(vertex): h = [(depth[vertex], vertex)] seen = {} while h: d, n = heapq.heappop(h) if n not in seen: seen[n] = 1 yield (d, n) for p in pfunc(n): heapq.heappush(h, (depth[p], p)) def generations(vertex): sg, s = None, {} for g, v in ancestors(vertex): if g != sg: if sg: yield sg, s sg, s = g, {v:1} else: s[v] = 1 yield sg, s x = generations(a) y = generations(b) gx = x.next() gy = y.next() # increment each ancestor list until it is closer to root than # the other, or they match try: while 1: if gx[0] == gy[0]: for v in gx[1]: if v in gy[1]: return v gy = y.next() gx = x.next() elif gx[0] > gy[0]: gy = y.next() else: gx = x.next() except StopIteration: return None