Hi,
Here is the new version of the merge algorithm patch.
The major changes compared to the previous patch are:
* No more messing around with merge-cache. git-ls-files used to get
the unmerged entries instead.
* The python code is now contained in two files, git-merge-script and
gitMergeCommon.py.
* The user interface is identical to the interface provided by
git-resolve-script
* In the non-clean case the unmerged cache entries will not be
removed from the cache.
I have also attached a test script which can redo every merge in a
repository with both git-resolve-script and git-merge-script. It will
report any non-clean merges and non-identical results for clean
merges. Do _not_ use this script in repositories you care about. It
calls 'git reset --hard' repeatedly and will probably not leave the
repository in its original state when it's done.
Of the 500 merge commits that currently exists in the kernel
repository 19 produces non-clean merges with git-merge-script. The
four merge cases listed in
<[EMAIL PROTECTED]> are cleanly merged by
git-merge-script. Every merge commit which is cleanly merged by
git-resolve-script is also cleanly merged by git-merge-script,
furthermore the results are identical. There are currently two merges
in the kernel repository which are not cleanly merged by
git-resolve-script but are cleanly merged by git-merge-script.
I guess the need for this has decreased with Daniel's new read-tree
code. Is there any chance of getting this code merged into mainline
git?
- Fredrik
#!/usr/bin/env python
import sys, math, random, os, re, signal, tempfile, time
from heapq import heappush, heappop
from sets import Set
from gitMergeCommon import *
def mergeMerge(a, b):
print 'Running merge-script HEAD', b.sha, '...'
[out, code] = runProgram(['git-merge-script', 'HEAD', b.sha, 'merge message'],
returnCode=True, pipeOutput=False)
if code == 0:
return True
else:
return False
def gitResolveMerge(a, b):
print 'Running git resolve HEAD', b.sha, '...'
[out, code] = runProgram(['git', 'resolve', 'HEAD', b.sha, 'merge message'],
returnCode=True, pipeOutput=False)
if code == 0:
return True
else:
return False
def doWork(graph, commits):
print 'commits:', repr(commits)
result = []
totalMergeTime = 0
totalResolveTime = 0
numCommits = 0
try:
for commit in graph.commits:
if len(commits) > 0 and not (commit.sha in commits):
continue
if len(commit.parents) > 1:
res = commit.sha + ' : '
if len(commit.parents) == 2:
numCommits += 1
print '---------------------------------------'
print 'Testing commit', commit.sha, '(tree)', commit.tree()
a = commit.parents[0]
b = commit.parents[1]
runProgram(['git-reset-script', '--hard', a.sha])
print 'Running git resolve...'
stdout.flush()
startTime = time.time()
resResolve = gitResolveMerge(a, b)
timeResolve = time.time() - startTime
totalResolveTime += timeResolve
if resResolve:
resolveHead = Commit(runProgram(['git-rev-parse', '--verify', 'HEAD']).rstrip(), [a, b])
runProgram(['git-reset-script', '--hard', a.sha])
print 'Running merge...'
stdout.flush()
startTime = time.time()
resMerge = mergeMerge(a, b)
timeMerge = time.time() - startTime
totalMergeTime += timeMerge
if resMerge:
mergeHead = Commit(runProgram(['git-rev-parse', '--verify', 'HEAD']).rstrip(), [a, b])
res += 'time r: ' + str(int(timeResolve)) + ' m: ' + str(int(timeMerge)) + '\t'
if resResolve and resMerge:
if resolveHead.tree() == mergeHead.tree():
res += 'Identical result'
else:
res += 'Non-identical results! resolve: ' + resolveHead.sha + \
' merge: ' + mergeHead.sha
else:
if resResolve:
res += 'resolve succeeded (' + resolveHead.sha + '), '
else:
res += 'resolve failed, '
if resMerge:
res += 'merge succeeded (' + mergeHead.sha + ')'
else:
res += 'merge failed'
else:
res += 'Ignoring octupus merge'
print res
result.append(res)
stdout.flush()
finally:
print '\n\n\nResults:'
for r in result:
print r
print 'Avg resolve time:', float(totalResolveTime) / numCommits
print 'Avg merge time:', float(totalMergeTime) / numCommits
def writeHead(head, sha):
if sha[-1] != '\n':
sha += '\n'
try:
f = open(os.environ['GIT_DIR'] + '/' + head, 'w')
f.write(sha)
f.close()
except IOError, e:
print 'Failed to write to', os.environ['GIT_DIR'] + '/' + head + ':', e.strerror
sys.exit(1)
return True
stdout = sys.stdout
setupEnvironment()
repoValid()
head = runProgram(['git-rev-parse', '--verify', 'HEAD^0']).rstrip()
print 'Building graph...'
stdout.flush()
graph = buildGraph([head])
print 'Graph building done.'
stdout.flush()
print 'Processing', len(graph.commits), 'commits (' + \
str(len([x for x in graph.commits if len(x.parents) > 1])) + ' merge commits)...'
originalHead = open('.git/HEAD', 'r').read()
print 'Original head:', originalHead
stdout.flush()
writeHead('original-head', originalHead)
try:
doWork(graph, sys.argv[1:])
finally:
writeHead('HEAD', originalHead)
