efficient way to filter several branches with common history?

4 messages, 3 authors, 2016-06-15 · open the first message on its own page

efficient way to filter several branches with common history?

From: Steffen Prohaska <hidden>
Date: 2016-06-15 22:43:19

Is there an efficient way to filter several branches at once
through git-filter-branch? Often several branches have a lot
of common history. Therefore, I suspect it would be much more
efficient to filter them with one call to git-filter-branch.
For example how can I efficiently filter all origin/* branches
to filtered/* branches?

	Steffen

Re: efficient way to filter several branches with common history?

From: Johannes Sixt <hidden>
Date: 2016-06-15 22:43:19

Steffen Prohaska wrote:
Is there an efficient way to filter several branches at once
through git-filter-branch? Often several branches have a lot
of common history. Therefore, I suspect it would be much more
efficient to filter them with one call to git-filter-branch.
For example how can I efficiently filter all origin/* branches
to filtered/* branches?
That feature is not yet implemented.

In the meantime do it this way:

Make an octopus merge of the branches onto a new branch. (If you have
more than a dozen or so, you better make a hierarchy of octopusses.) You
don't need to resolve conflicts (you are not interested in the merge
result), or use -s ours to avoid them in the first place.
Then filter that new branch.
Then create new refs at the rewritten commits:

   $ git update-ref refs/filtered/b1 $id-of-rewritten-origin/b1
   $ ...

Use gitk to find the $ids-of-rewritten-origin/*

-- Hannes

Re: efficient way to filter several branches with common history?

From: Steffen Prohaska <hidden>
Date: 2016-06-15 22:43:19

On Jul 4, 2007, at 10:37 AM, Johannes Sixt wrote:
Steffen Prohaska wrote:
quoted
Is there an efficient way to filter several branches at once
through git-filter-branch? Often several branches have a lot
of common history. Therefore, I suspect it would be much more
efficient to filter them with one call to git-filter-branch.
For example how can I efficiently filter all origin/* branches
to filtered/* branches?
That feature is not yet implemented.

In the meantime do it this way:

Make an octopus merge of the branches onto a new branch. (If you have
more than a dozen or so, you better make a hierarchy of  
octopusses.) You
don't need to resolve conflicts (you are not interested in the merge
result), or use -s ours to avoid them in the first place.
Then filter that new branch.
Then create new refs at the rewritten commits:

   $ git update-ref refs/filtered/b1 $id-of-rewritten-origin/b1
   $ ...

Use gitk to find the $ids-of-rewritten-origin/*
Thanks for your explanation. The following is the template I used
to build my fully automated version of what you proposed:
--- SNIP ---
echo "merging branches to be filtered ..."
git-checkout -b tmp/all origin/master

for b in origin/branchX origin/branchY [ ... more branches here ...]
do
     git merge -s ours -m "merge-for-preparing-filter-branch $b" $b
done

echo "... filtering ..."
git-filter-branch \
[... your git-filter-branch filters here ...] \
   filtered/all >filter-branch.log

echo "... setting heads of filtered branches."
lastp1=
git-log --pretty="format:%s %P" filtered/all |
while read t b p1 p2
do
     [[ "$t" == "merge-for-preparing-filter-branch" ]] || { git  
update-ref refs/heads/filtered/master $lastp1 ; break ; }
     b=filtered/$(basename $b)
     git update-ref refs/heads/$b $p2
     lastp1=$p1
done

echo "delete tmp/all and filtered/all after checking the result"
--- SNIP ---
	Steffen

Re: efficient way to filter several branches with common history?

From: Johannes Schindelin <hidden>
Date: 2016-06-15 22:43:19

Hi,

On Wed, 4 Jul 2007, Steffen Prohaska wrote:
On Jul 4, 2007, at 10:37 AM, Johannes Sixt wrote:
quoted
Steffen Prohaska wrote:
quoted
Is there an efficient way to filter several branches at once
through git-filter-branch?
That feature is not yet implemented.

In the meantime do it this way:

[...]
Thanks for your explanation. The following is the template I used
to build my fully automated version of what you proposed:

[...]
Since you seem quite proficient in shell, why not implement this feature 
in filter-branch (which is a shell script) to begin with?

Ciao,
Dscho
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help