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A possible subtree split bug

From
FPFabien POTENCIER <fabien.potencier@gmail.com>
Date
Jul 31, 2012, 11:21 UTC
Message-ID
<5017BFB0.9070701@gmail.com>
Hi all,

I've encountered what I think is a bug in the subtree split command included in contrib.

According to the docs:

"Repeated splits of exactly the same history are guaranteed to be identical (ie. to produce the same commit ids). Because of this, if you add new commits and then re-split, the new commits will be attached as commits on top of the history you generated last time..."

But unfortunately, that's not always the case.

I've found that if you have a commit that reverts the previous one and then merge a branch where those two commits did not exist, then the next time you split, they won't be present anymore in the split tree.

Here is a simple script that exhibits the issue:
#!/bin/sh
git init

# create a directory that is going to be split mkdir doc echo "TEST" > doc/README git add doc # commit A git ci -a -m"first version"

# create a branch with a new commit (Z) git co -b test echo "TEST" > doc/README1 git add doc/README1 git ci -a -m"added README1" git co master

# modify the README file (commit B) echo "TEST_" > doc/README git ci -a -m"second version"

# revert the change (commit C) echo "TEST" > doc/README git ci -a -m"revert second version"

# split git subtree split --prefix="doc" --branch=TARGET

# the log will show the 3 commits as expected (including B and C) git log --oneline TARGET

# merge the test branch git merge -m"merged test" test

# re-split # deleting the target as the bug prevents the split to happen correctly git branch -D TARGET git subtree split --prefix="doc" --branch=TARGET

# the 2 commits B and C are not in the split anymore # the split will only show A then Z which is not the expected result git log --oneline TARGET

Fabien
-- 
Fabien Potencier
Sensio CEO - Symfony lead developer
sensiolabs.com | symfony.com | fabien.potencier.org
Tél: +33 1 40 99 80 80
Next: greened@obbligato.org
Message 1 of 2 in “A possible subtree split bug”
  1. Fabien POTENCIERJul 31, 2012
  2. greened@obbligato.orgAug 21, 2012

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