merge: forcefully mark files that we get from the second parent as dirty
After a hg merge, we want to include in the commit all the files that we
got from the second parent, so that we have the correct file-level
history. To make them visible to hg commit, we try to mark them as dirty.
Unfortunately, right now we can't really mark them as dirty[1] - the
best we can do is to mark them as needing a full comparison of their
contents, but they will still be considered clean if they happen to be
identical to the version in the first parent.
This changeset extends the dirstate format in a compatible way, so that
we can mark a file as dirty:
Right now we use a negative file size to indicate we don't have valid
stat data for this entry. In practice, this size is always -1.
This patch uses -2 to indicate that the entry is dirty. Older versions
of hg won't choke on this dirstate, but they may happily mark the file
as clean after a full comparison, destroying all of our hard work.
The patch adds a dirstate.normallookup method with the semantics of the
current normaldirty, and changes normaldirty to forcefully mark the
entry as dirty.
This should fix issue522.
[1] - well, we could put them in state 'm', but that state has a
different meaning.
# 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