Move cmdtable and reposetup handling out of extensions.py
A new function (extensions.extensions) allows the code that is
interested in those attributes to handle them directly.
This allows some cleanups of extensions.py. Notably, we can
remove the extensions.commandtable hack.
It also makes it easier to add standard extension attributes,
like a "hgwebsetup" function or a "helptable" dict that augments
the data in help.py, etc.
# 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