Re: [PATCH] submodule absorbgitdirs: use relative <from> and <to> paths
- From
Glen Choo <chooglen@google.com>
- Date
- Nov 23, 2022, 00:43 UTC
- Message-ID
- <kl6l7czmec10.fsf@chooglen-macbookpro.roam.corp.google.com>
- In-Reply-To
- <patch-1.1-065be1da895-20221122T224306Z-avarab@gmail.com>
I think we might be better off reverting a79e56cb0a6 than trying to fix forward. But before getting into that, thanks for reading the report and sending a fix :)
Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes:
Rearranging the thread slightly,
Show 8 quoted lines
>> - If "absorbgitdirs" becomes consistent with other "git submodule" >> subcommands and prints relative paths to submodules, then this >> produces the wrong result. > It's harder to narrowly fix that problem than to just have > relocate_single_git_dir_into_superproject() display the same sorts of > paths we do for most other "submodule" commands. I.e. the "<to>" > should be relative to the "<from>" path, rather than relative to the > eventual superproject.
As I noted here and in the initial report [1], the relative path is from the original CWD to the submodule, not from 'old submodule gitdir' to 'new submodule gitdir', so I wouldn't really consider this consistent with other "submodule" commands.
Besides that, I also don't find the output intuitive..
[1] https://lore.kernel.org/git/kl6lmt8qv9gc.fsf@chooglen-macbookpro.roam.corp.google.com/
Show 23 quoted lines
> diff --git a/submodule.c b/submodule.c
> index c47358097fd..a464c99a27f 100644
> --- a/submodule.c
> +++ b/submodule.c
> @@ -2271,9 +2271,12 @@ int validate_submodule_git_dir(char *git_dir, const char *submodule_name)
> static void relocate_single_git_dir_into_superproject(const char *path)
> {
> char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
> + char *rel_old_git_dir;
> + const char *rel_new_git_dir;
> struct strbuf new_gitdir = STRBUF_INIT;
> const struct submodule *sub;
> - size_t off = 0;
> + const char *super_prefix = get_super_prefix();
> + const char *sp = super_prefix ? super_prefix : "";
>
> if (submodule_uses_worktrees(path))
> die(_("relocate_gitdir for submodule '%s' with "
> @@ -2285,6 +2288,7 @@ static void relocate_single_git_dir_into_superproject(const char *path)
> return;
>
> real_old_git_dir = real_pathdup(old_git_dir, 1);
> + rel_old_git_dir = xstrfmt("%s%s", sp, old_git_dir);rel_old_git_dir is relative to the root of the superproject's worktree.
Show 12 quoted lines
> @@ -2293,23 +2297,23 @@ static void relocate_single_git_dir_into_superproject(const char *path)
> submodule_name_to_gitdir(&new_gitdir, the_repository, sub->name);
> if (validate_submodule_git_dir(new_gitdir.buf, sub->name) < 0)
> die(_("refusing to move '%s' into an existing git dir"),
> - real_old_git_dir);
> + rel_old_git_dir);
> if (safe_create_leading_directories_const(new_gitdir.buf) < 0)
> die(_("could not create directory '%s'"), new_gitdir.buf);
> +
> real_new_git_dir = real_pathdup(new_gitdir.buf, 1);
> + rel_new_git_dir = relative_path(real_new_git_dir, real_old_git_dir,
> + &new_gitdir);rel_new_git_dir is relative to rel_old_git_dir
Show 8 quoted lines
>
> - while (real_old_git_dir[off] && real_new_git_dir[off] &&
> - real_old_git_dir[off] == real_new_git_dir[off])
> - off++;
> fprintf(stderr, _("Migrating git directory of '%s%s' from '%s' to '%s'\n"),
> - get_super_prefix_or_empty(), path,
> - real_old_git_dir + off, real_new_git_dir + off);
> + sp, path, rel_old_git_dir, rel_new_git_dir);and the submodule is also relative to the root of the superproject's worktree...
Show 13 quoted lines
> diff --git a/t/t7412-submodule-absorbgitdirs.sh b/t/t7412-submodule-absorbgitdirs.sh > index a5cd6db7ac2..0afa0fe3a83 100755 > --- a/t/t7412-submodule-absorbgitdirs.sh > +++ b/t/t7412-submodule-absorbgitdirs.sh > @@ -27,7 +27,7 @@ test_expect_success 'absorb the git dir' ' > git status >expect.1 && > git -C sub1 rev-parse HEAD >expect.2 && > cat >expect <<-\EOF && > - Migrating git directory of '\''sub1'\'' from '\''sub1/.git'\'' to '\''.git/modules/sub1'\'' > + Migrating git directory of '\''sub1'\'' from '\''sub1/.git'\'' to '\''../../.git/modules/sub1'\'' > EOF > git submodule absorbgitdirs 2>actual && > test_cmp expect actual &&
So when we print the 3 relative paths here, they don't all share the same base, which I find quite unintuitive to parse.
The 'obvious' solution to make this relative to the original CWD is to plumb the relative path in --super-prefix (like the other "git submodule" commands), but that won't give the right result in all cases either, since we found a call site that gets --super-prefix from "git read-tree" [2], in which case, --super-prefix is relative to the root of the worktree and not the original CWD. I don't think we should pursue this.
A more workable fix (and a possible future direction for removing --super-prefix) would be to pass "--original-cwd" instead of "--super-prefix", which would let the child process resolve the relative path correctly. That's a big change though, and I don't think it's worth doing right now, especially with 'remove --super-prefix' underway.
So for now, I'd strongly prefer we either eject or revert a79e56cb0a6.
[2] https://lore.kernel.org/git/cover-v3-0.9-00000000000-20221119T122853Z-avarab@gmail.com