On Wed, Dec 19, 2018 at 10:46:52PM +0100, Martin Ågren wrote: > > 2. Arguably we should not even look at extensions.* unless we see a > > version >= 1. But we do process them as we parse the config file. > > This is mostly an oversight, I think. We have to handle them as we > > see them, because they may come out of order with respect to the > > repositoryformatversion field. But we could put them into a > > string_list, and then only process them after we've decided which > > version we have. > > I hadn't thought too much about this. I guess that for some simpler > extensions--versions dependencies it would be feasible to first parse > everything, then, depending on the version we've identified, forget > about any "irrelevant" extensions. Again, nothing I've thought much > about, and seems to be safely out of scope for this patch. The decision is actually pretty straight-forward: if version < 1, ignore extensions, otherwise respect them (and complain about any we don't know about). So I think we could just do in verify_repository_format() something like: if (version < 1) { /* "undo" any extensions we might have parsed */ data->precious_objects = 0; FREE_AND_NULL(data->partial_clone); data->worktree_config = 0; data->hash_algo = GIT_HASH_SHA1; } else { /* complain about unknown extension; we already do this! */ } It's a little ugly to have to know about all the extensions here, but we already initialize them in read_repository_format(). We could probably factor that out into a shared function. -Peff