gitattributes - clean filter invoked on pull?

Hi,

Background: We at LibreOffice are trying to use the 'filter'
gitattributes feature to clean up line wrappings in po files.

The problem is that it seems the clean filter - which is supposed to be invoked only in case a new blob is created - is invoked even on clone/pull, and other developers are claiming that it slows down their workflow.

Is this a bug? I don't exactly understand why this would be necessary.

Here is a short script to reproduce the issue:

---- rm -rf client* mkdir client cd client git init git config filter.po.clean 'echo foo >&2 && cat' git config filter.po.smudge cat echo '*.po filter=po' > .gitattributes touch foo.po git add .gitattributes foo.po git commit -m foo cd .. git clone client client2 cd client2 git config filter.po.clean 'echo foo >&2 && cat' git config filter.po.smudge cat cd .. cd client echo aaa > foo.po git commit -am second cd .. cd client2/ git pull ----

Its output here with 1.7.4.4:

----
$ sh test.sh 
Initialized empty Git repository in /home/vmiklos/git/t/client/.git/
foo
foo
[master (root-commit) bbf8490] foo
foo
 1 files changed, 1 insertions(+), 0 deletions(-)
 create mode 100644 .gitattributes
 create mode 100644 foo.po
Cloning into client2...
done.
foo
[master foo
foo
e37f5ab] second
foo
foo
 1 files changed, 1 insertions(+), 0 deletions(-)
remote: Counting objects: 5, done.
remote: Compressing objects: 100% (2/2), done.
remote: Total 3 (delta 0), reused 0 (delta 0)
Unpacking objects: 100% (3/3), done.
From /home/vmiklos/git/t/client
   bbf8490..e37f5ab  master     -> origin/master
Updating bbf8490..e37f5ab
foo
Fast-forward
foo
 foo.po |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
----

Any thoughts why the clean filter is invoked on pull?

Thanks.