Hi,
Stefan Sperling asked me to post some details in respect of a suggestion I
wanted to make for issue 3830
http://subversion.tigris.org/issues/show_bug.cgi?id=3830
It took me some time to understand that it is _not_ possible for the svn client
to display the future of an object in some revision when it no longer resists
on the initial path or was replaced by another object on the same path.
Well, here is the pseudo code of my algorithm to determine the forward history
& backward history of a svn path@peg in logarithmic time (it should terminate
quickly in most real world situations):
log[] getFullRemoteLog(urlOfObject, revOfObject)
url = urlOfObject
peg = revOfObject
// start to fetch complete forward & backward log of url@peg
endRev = repsitory.getLastChangedRevision()
try
// first try the regular way
// using HEAD instead of HEAD's rev number as
endRev produces wrong results in svn 1.6.
// see
http://subversion.tigris.org/issues/show_bug.cgi?id=3931
return svn log url@peg -r endRev:1
catch exception
// OK, no problem. Remote file does no longer
exist on HEAD. Proceed.
startRev = peg
youngestRev = determineYoungestRevision(url, startRev.number(),
endRev.number(), false)
return svn log url@peg -r youngestRev:1
rev determineYoungestRevision(url, startRev, endRev, objectFound)
if startRev == endRev
return startRev
testRev = startRev + (endRev - startRev) / 2
if objectFound
try
svn info url@testRev -r startRev
// test revision exists =>
proceed forward in history
determineYoungestRevision(url,
testRev, endRev, true)
catch exception
// test revision does not exist
=> go backward in history
determineYoungestRevision(url,
startRev, testRev - 1 , true)
// right object not yet found
try
log[] = svn log url@testRev -r testRev:1
// object hit! But is it the right one?
for i:log.length // no need to improve as svn
requests dominate Running time
if log[i - 1].getRevision() >=
startRev && log[i].getRevision() <= startRev
// right object
found! Now find youngest object revision.
return
determineYoungestRevision(url, log[0].getRevision(), endRev, true)
// not the right object!
return determineYoungestRevision(url, startRev,
log[log.length - 1].getRevision() - 2, false)
catch exception
// no object hit!
return determineLastYoungestRevision(url,
startRev, testRev.getNumber() - 1, false)
Greetings,
Julian
p.s. please cc me. I am not subscribed
