> Yuki Kokubun <[email protected]> writes:
>
> > "git filter-branch -- --all" can be confused when refs that refer to objects
> > other than commits or tags exists.
> > Because "git rev-parse --all" that is internally used can return refs that
> > refer to an object other than commit or tag. But it is not considered in the
> > phase of updating refs.
>
> Could you describe what the consequence of that is? We have a ref
> that points directly at a blob object, or a ref that points at a tag
> object that points at a blob object. The current code leaves both of
> these refs in "$tempdir/heads". Then...?
Sorry, this is my wrong.
I wrongly thought only refs/replace can point at a blob or tree object.
>
> ... goes and looks ...
>
> There is a loop that looks like this:
>
> while read ref
> do
> sha1=$(git rev-parse "$ref^0")
> ...
> done <"$tempdir/heads"
>
> which would break on anything but a commit-ish.
>
> > # The refs should be updated if their heads were rewritten
> > git rev-parse --no-flags --revs-only --symbolic-full-name \
> > - --default HEAD "$@" > "$tempdir"/raw-heads || exit
> > + --default HEAD "$@" > "$tempdir"/raw-objects || exit
> > +# refs/replace can refer to an object other than commit or tag
>
> Mention of replace refs in the proposed log message gives an easy to
> understand example and is a good idea, but this in code comment does
> not have to single out the replace refs. A tag can also point at an
> object with any type, e.g. "git tag v2.6.11-tree v2.6.11^{tree}"
> would make "refs/tags/v2.6.11-tree" point at the tree at the top
> level of the tree-ish "v2.6.11". It probably is OK to drop this
> comment altogether.
OK, I'm gonna drop the incorrect comment.
>
> > +while read ref
> > +do
> > + type=$(git cat-file -t "$ref")
> > + if test $type = commit || test $type = tag
> > + then
> > + echo "$ref"
> > + fi
> > +done >"$tempdir"/raw-heads <"$tempdir"/raw-objects
> > sed -e '/^^/d' "$tempdir"/raw-heads >"$tempdir"/heads
>
> So... is the idea to limit the set of refs to be rewritten to those
> that point at commits and tags? As I already alluded to, I do not
> think you want to accept a ref that points at any tag object---only
> the ones that point at a tag that points at a commit-ish, so that
> the code will not barf when doing "$ref^0".
>
> So perhaps
>
> git rev-parse --no-flags ... >"$tempdir/raw-heads" || exit
>
> while read ref
> do
> case "$ref" in ^?*) continue ;; esac
> if git rev-parse --verify "$ref^0" 2>/dev/null
> then
> echo "$ref"
> fi
> done >"$tempdir/heads" <"$tempdir/raw-heads"
>
> or something? Note that you do not need the "sed" as the loop
> already excludes the negative revs.
I feel using "git rev-parse --verify" is a good way as you said.
I'm gonna modify the patch to use it.
>
> > test -s "$tempdir"/heads ||
> > diff --git a/t/t7003-filter-branch.sh b/t/t7003-filter-branch.sh
> > index 7cb60799b..efeaf5887 100755
> > --- a/t/t7003-filter-branch.sh
> > +++ b/t/t7003-filter-branch.sh
> > @@ -470,4 +470,17 @@ test_expect_success 'tree-filter deals with object
> > name vs pathname ambiguity' '
> > git show HEAD:$ambiguous
> > '
> >
> > +test_expect_success 'rewrite repository including refs/replace that point
> > to non commit object' '
> > + test_when_finished "git reset --hard original" &&
> > + tree=$(git rev-parse HEAD^{tree}) &&
> > + test_when_finished "git replace -d $tree" &&
> > + echo A >new &&
> > + git add new &&
> > + new_tree=$(git write-tree) &&
> > + git replace $tree $new_tree &&
>
> Perhaps something like this here:
>
> git tag -a "tag to a tree" treetag $new_tree &&
>
> can tell su how well it works with a tag that points at a tree?
Sounds good. I'm gonna add such tags to the test case.
>
> > + git reset --hard HEAD &&
> > + git filter-branch -f -- --all >filter-output 2>&1 &&
> > + ! fgrep fatal filter-output
> > +'
> > +
> > test_done