> > Another thing you need to clarify is what happens if the fetch-by-commit
> > fails. Right now, it seems that it will make the whole thing fail, which
> > might be a surprising change in behavior.
>
> But a positive surprise, I would assume?
Whether positive or negative, I think that this needs to be mentioned in
the commit message.
As for positive or negative, I tend to agree that it's positive - sure,
some previously successful fetches would now fail, but the results of
those fetches could not be recursively checked out anyway.
> > The test stores the result in a normal branch, not a remote tracking
> > branch. Is storing in a normal branch required?
>
> In the test we fetch from another repository, such that in the
> repository-under-test this will show up in a remote tracking branch?
If that were true, I would expect that when this line:
> git fetch --recurse-submodules --recurse-submodules-default on-demand origin refs/changes/2:refs/heads/my_branch &&
is replaced by this line:
> git fetch --recurse-submodules --recurse-submodules-default on-demand origin refs/changes/2 &&
then things would still work. The tests pass with the first line (after
I fixed a type mismatch) but not with the second. (Also I don't think a
remote-tracking branch is generated here - the output printed doesn't
indicate so, and refs/changes/2 is not a branch anyway.)
> > Also, do you know why this is required? A naive reading of the patch
> > leads me to believe that this should work even if merely fetching to
> > FETCH_HEAD.
>
> See the next patch, check_for_new_submodule_commits() is missing
> for FETCH_HEAD.
I see in the next patch that there is an "if" branch in
store_updated_refs() without update_local_ref() in which
"check_for_new_submodule_commits(&rm->old_oid)" needs to be inserted. I
think this is a symptom that maybe check_for_new_submodule_commits()
needs to be extracted from update_local_ref() and put into
store_updated_refs() instead? In update_local_ref(), it is called on
ref->new_oid, which is actually the same as rm->old_oid anyway (there is
an oidcpy earlier).
> > > +static const struct submodule *get_default_submodule(const char *path)
> > > +{
> > > + struct submodule *ret = NULL;
> > > + const char *name = default_name_or_path(path);
> > > +
> > > + if (!name)
> > > + return NULL;
> > > +
> > > + ret = xmalloc(sizeof(*ret));
> > > + memset(ret, 0, sizeof(*ret));
> > > + ret->path = name;
> > > + ret->name = name;
> > > +
> > > + return (const struct submodule *) ret;
> > > +}
> >
> > What is a "default" submodule and why would you need one?
>
> s/default/artificial/. Such a submodule is a submodule that has no
> config in the .gitmodules file and its name == path.
> We need to keep those around for historic reasons AFAICT, c.f.
> c68f837576 (implement fetching of moved submodules, 2017-10-16)
Ah, OK. I would call it a fake submodule then, and copy over the "No
entry in .gitmodules?" comment.
> > Will task->sub ever be NULL?
>
> Yes, if we fall back to these "default" submodule and just try if it
> can be handled
> as a submodule, but it cannot be handled as such,
> get_next_submodule_task_create has
>
> task->sub = submodule_from_path(r, &null_oid, path);
> if (!task->sub) {
> task->sub = get_default_submodule(path);
>
> and get_default_submodule can return NULL.
Ah, yes you're right.
