Re: [PATCH v2 00/18] submodule: remove "--recursive-prefix"

[Glen Choo <chooglen@google.com>]

Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes:

> On Thu, Jun 30 2022, Glen Choo via GitGitGadget wrote:
>
>> = Series history
>>
>> Changes in v2:
>>
>>  * Rebase onto ab/submodule-cleanup (previously master)
>>  * Cherry pick https://github.com/avar/git/commit/f445c57490d into 4/6
>>  * Style fixes in .c and tests
>
> Thanks for the update, Looks like something happened with GGG to send
> the base series + yours, I confirmed that 1-13/18 are the same as my
> series in gitster/ab/submodule-cleanup.

Yes, oops. I resent this as v3 (sans your base), but you can ignore
that :P

> I played around with this a bit, and pushed some amends to
> https://github.com/avar/git/tree/avar/pr-git-1282/chooglen/submodule/remove-recursive-prefix-v2;
> which you should take more as the results of poking around, I think this
> is fine as-is if Junio would like to pick it up, sans the possible bug
> mentioned below.
>
> A range-diff of the changes I made follows below, changes:
>
>  * Split up the "add tests" to a new commit :) You mentioned
>    "test_expect_failure", I just assumed we'd use test_expect_succes,
>    and then the 2nd commit has this test change:
> 	
> 	diff --git a/t/t7406-submodule-update.sh b/t/t7406-submodule-update.sh
> 	index 9a076e025f3..6cc07460dd2 100755
> 	--- a/t/t7406-submodule-update.sh
> 	+++ b/t/t7406-submodule-update.sh
> 	@@ -1163 +1163 @@ test_expect_success 'submodule update should skip unmerged submodules' '
> 	-       Skipping unmerged submodule middle//bottom
> 	+       Skipping unmerged submodule middle/bottom
> 	@@ -1176 +1176 @@ test_expect_success 'submodule update --recursive skip submodules with strategy=
> 	-       Skipping submodule '\''../middle/'\''
> 	+       Skipping submodule '\''middle/bottom'\''
>
>    Which I think makes it much easier to explain the change itself, the
>    first commit basically just says "tests for existing behavior, see
>    the next commit for details".

Ah, I see what you meant now. Makes sense.

>  * Used test_cmp instead of "grep -F", makes for easier to grok output :)
>
>  * I had to squint a bit at the change from strvec_pushl() to
>    strvec_pushf().
>
>    I.e. we're changing both that we're passing "--foo bar"
>    v.s. "--foo=bar" *and* "bar" v.s. "bar/", but as the commit message
>    notes it's just the latter that matters.
>
>    Just a nit, but I think it's a bit easier to reason about just
>    changing the one thing we need to change there, although that means
>    giving the "if" braces. This also leaves the "--super-prefix" code
>    consistent with all the other places where we
>    "strvec.*--super-prefix" at the end.

Both sound good.

>  * We can just declare some of the variables and initialize them at the
>    beginning, but couldn't when they were a strbuf.

I think this is just "char *displaypath" in 2/7 aka d1a47d302e
(submodule--helper update: use display path helper, 2022-06-28)? That
change makes sense.

>  * Your 18/18 has some odd code formatting of "var =\n\t\tvalue(..."
>    when we usually do "var = value(...\n...".

Thanks for catching that. I could have sworn that came from "make
style".

>  * You appear to have (and I haven't "fixed" it here) in 13/18 mentioned
>    "While we're fixing the display names, also fix inconsistent quoting
>    of the submodule name", but as the test_cmp shows we appear not to
>    have done that part at all? Is this referring to a forgotten change
>    where we should be saying (note the added '-quotes):
>
>        Skipping unmerged submodule 'middle/bottom'
>
>    Either that's what you mean & you forgot, or we're missing a test, or
>    I'm misunderstanding it...

Yes, this is a genuine error. In v2, I dropped this change (as you
suggested) and I neglected to amend the comit message..

> I hope this helps, at least some of it...

Thanks! Yes it helps a lot. If you don't mind, I'll roll your commits +
the commit message fix as v4.

> 1:  64c138df196 ! 1:  3d9977006d3 submodule--helper update: use display path helper
>     @@ Metadata
>      Author: Glen Choo <chooglen@google.com>
>      
>       ## Commit message ##
>     -    submodule--helper update: use display path helper
>     +    submodule--helper tests: add missing "display path" coverage
>      
>          There are two locations in prepare_to_clone_next_submodule() that
>     -    manually calculate the submodule display path, but should just use
>     -    do_get_submodule_displaypath() for consistency.
>     -
>     -    Do this replacement and reorder the code slightly to avoid computing
>     -    the display path twice.
>     -
>     -    This code was never tested, and adding tests shows that both these sites
>     -    have been computing the display path incorrectly ever since they were
>     -    introduced in 48308681b0 (git submodule update: have a dedicated helper
>     -    for cloning, 2016-02-29) [1]:
>     -
>     -    - The first hunk puts a "/" between recursive_prefix and ce->name, but
>     -      recursive_prefix already ends with "/".
>     -    - The second hunk calls relative_path() on recursive_prefix and
>     -      ce->name, but relative_path() only makes sense when both paths share
>     -      the same base directory. This is never the case here:
>     -      - recursive_prefix is the path from the topmost superproject to the
>     -        current submodule
>     -      - ce->name is the path from the root of the current submodule to its
>     -        submodule.
>     -      so, e.g. recursive_prefix="super" and ce->name="submodule" produces
>     -      displayname="../super" instead of "super/submodule".
>     -
>     -    While we're fixing the display names, also fix inconsistent quoting of
>     -    the submodule name.
>     -
>     -    [1] I verified this by applying the tests to 48308681b0.
>     +    manually calculate the submodule display path, as discussed in the
>     +    next commit the "Skipping" output isn't exactly what we want, but
>     +    let's test how we behave now, before changing the existing behavior.
>      
>          Signed-off-by: Glen Choo <chooglen@google.com>
>     -
>     - ## builtin/submodule--helper.c ##
>     -@@ builtin/submodule--helper.c: static int prepare_to_clone_next_submodule(const struct cache_entry *ce,
>     - 	const char *update_string;
>     - 	enum submodule_update_type update_type;
>     - 	char *key;
>     --	struct strbuf displaypath_sb = STRBUF_INIT;
>     - 	struct strbuf sb = STRBUF_INIT;
>     --	const char *displaypath = NULL;
>     -+	char *displaypath;
>     - 	int needs_cloning = 0;
>     - 	int need_free_url = 0;
>     - 
>     -+	displaypath = do_get_submodule_displaypath(ce->name,
>     -+						   suc->update_data->prefix,
>     -+						   suc->update_data->recursive_prefix);
>     -+
>     - 	if (ce_stage(ce)) {
>     --		if (suc->update_data->recursive_prefix)
>     --			strbuf_addf(&sb, "%s/%s", suc->update_data->recursive_prefix, ce->name);
>     --		else
>     --			strbuf_addstr(&sb, ce->name);
>     --		strbuf_addf(out, _("Skipping unmerged submodule %s"), sb.buf);
>     -+		strbuf_addf(out, _("Skipping unmerged submodule %s"), displaypath);
>     - 		strbuf_addch(out, '\n');
>     - 		goto cleanup;
>     - 	}
>     - 
>     - 	sub = submodule_from_path(the_repository, null_oid(), ce->name);
>     - 
>     --	if (suc->update_data->recursive_prefix)
>     --		displaypath = relative_path(suc->update_data->recursive_prefix,
>     --					    ce->name, &displaypath_sb);
>     --	else
>     --		displaypath = ce->name;
>     --
>     - 	if (!sub) {
>     - 		next_submodule_warn_missing(suc, out, displaypath);
>     - 		goto cleanup;
>     -@@ builtin/submodule--helper.c: static int prepare_to_clone_next_submodule(const struct cache_entry *ce,
>     - 					      "--no-single-branch");
>     - 
>     - cleanup:
>     --	strbuf_release(&displaypath_sb);
>     -+	free(displaypath);
>     - 	strbuf_release(&sb);
>     - 	if (need_free_url)
>     - 		free((void*)url);
>     +    Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
>      
>       ## t/t7406-submodule-update.sh ##
>      @@ t/t7406-submodule-update.sh: test_expect_success 'submodule update --filter sets partial clone settings' '
>     @@ t/t7406-submodule-update.sh: test_expect_success 'submodule update --filter sets
>      +	# because of its unmerged state
>      +	test_config -C top-cloned submodule.middle.update !true &&
>      +	git -C top-cloned submodule update --recursive 2>actual.err &&
>     -+	grep -F "Skipping unmerged submodule middle/bottom" actual.err
>     ++	cat >expect.err <<-\EOF &&
>     ++	Skipping unmerged submodule middle//bottom
>     ++	EOF
>     ++	test_cmp expect.err actual.err
>      +'
>      +
>      +test_expect_success 'submodule update --recursive skip submodules with strategy=none' '
>     @@ t/t7406-submodule-update.sh: test_expect_success 'submodule update --filter sets
>      +	test_commit -C top-cloned/middle/bottom downstream_commit &&
>      +	git -C top-cloned/middle config submodule.bottom.update none &&
>      +	git -C top-cloned submodule update --recursive 2>actual.err &&
>     -+	grep -F "Skipping submodule ${SQ}middle/bottom${SQ}" actual.err
>     ++	cat >expect.err <<-\EOF &&
>     ++	Skipping submodule '\''../middle/'\''
>     ++	EOF
>     ++	test_cmp expect.err actual.err
>      +'
>      +
>       test_done
> -:  ----------- > 2:  d1a47d302ee submodule--helper update: use display path helper
> 2:  d3e803a4630 ! 3:  a5b30ac94e6 submodule--helper: don't recreate recursive prefix
>     @@ builtin/submodule--helper.c: static void update_data_to_args(struct update_data
>      -	if (update_data->recursive_prefix)
>      -		strvec_pushl(args, "--recursive-prefix",
>      -			     update_data->recursive_prefix, NULL);
>     -+	if (update_data->displaypath)
>     -+		strvec_pushf(args, "--recursive-prefix=%s/",
>     -+			     update_data->displaypath);
>     ++	if (update_data->displaypath) {
>     ++		strvec_push(args, "--recursive-prefix");
>     ++		strvec_pushf(args, "%s/", update_data->displaypath);
>     ++	}
>       	if (update_data->quiet)
>       		strvec_push(args, "--quiet");
>       	if (update_data->force)
> 3:  1f7cf6ffaf1 = 4:  0ea102882a7 submodule--helper: use correct display path helper
> 4:  85e65f143b6 = 5:  8085bc83a0c submodule--helper: remove unused SUPPORT_SUPER_PREFIX flags
> 5:  1d8b6b244dc ! 6:  4c00a1b496a submodule--helper update: use --super-prefix
>     @@ builtin/submodule--helper.c: struct submodule_update_clone {
>       	enum submodule_update_type update_default;
>       	struct object_id suboid;
>      @@ builtin/submodule--helper.c: static int prepare_to_clone_next_submodule(const struct cache_entry *ce,
>     - 
>     - 	displaypath = do_get_submodule_displaypath(ce->name,
>     - 						   suc->update_data->prefix,
>     --						   suc->update_data->recursive_prefix);
>     -+						   get_super_prefix());
>     - 
>     - 	if (ce_stage(ce)) {
>     - 		strbuf_addf(out, _("Skipping unmerged submodule %s"), displaypath);
>     + 	char *key;
>     + 	struct update_data *ud = suc->update_data;
>     + 	char *displaypath = do_get_submodule_displaypath(ce->name, ud->prefix,
>     +-							 ud->recursive_prefix);
>     ++							 get_super_prefix());
>     + 	struct strbuf sb = STRBUF_INIT;
>     + 	int needs_cloning = 0;
>     + 	int need_free_url = 0;
>      @@ builtin/submodule--helper.c: static void update_data_to_args(struct update_data *update_data, struct strvec *
>       {
>       	enum submodule_update_type update_type = update_data->update_default;
>       
>      -	strvec_pushl(args, "submodule--helper", "update", "--recursive", NULL);
>      -	strvec_pushf(args, "--jobs=%d", update_data->max_jobs);
>     - 	if (update_data->displaypath)
>     --		strvec_pushf(args, "--recursive-prefix=%s/",
>     -+		strvec_pushf(args, "--super-prefix=%s/",
>     - 			     update_data->displaypath);
>     + 	if (update_data->displaypath) {
>     +-		strvec_push(args, "--recursive-prefix");
>     ++		strvec_push(args, "--super-prefix");
>     + 		strvec_pushf(args, "%s/", update_data->displaypath);
>     + 	}
>      +	strvec_pushl(args, "submodule--helper", "update", "--recursive", NULL);
>      +	strvec_pushf(args, "--jobs=%d", update_data->max_jobs);
>       	if (update_data->quiet)
> 6:  a21e8cd174d ! 7:  639f07e4b84 submodule--helper: remove display path helper
>     @@ builtin/submodule--helper.c: static void init_submodule(const char *path, const
>       	sub = submodule_from_path(the_repository, null_oid(), path);
>       
>      @@ builtin/submodule--helper.c: static int prepare_to_clone_next_submodule(const struct cache_entry *ce,
>     + 	enum submodule_update_type update_type;
>     + 	char *key;
>     + 	struct update_data *ud = suc->update_data;
>     +-	char *displaypath = do_get_submodule_displaypath(ce->name, ud->prefix,
>     +-							 get_super_prefix());
>     ++	char *displaypath = get_submodule_displaypath(ce->name, ud->prefix);
>     + 	struct strbuf sb = STRBUF_INIT;
>       	int needs_cloning = 0;
>       	int need_free_url = 0;
>     - 
>     --	displaypath = do_get_submodule_displaypath(ce->name,
>     --						   suc->update_data->prefix,
>     --						   get_super_prefix());
>     -+	displaypath =
>     -+		get_submodule_displaypath(ce->name, suc->update_data->prefix);
>     - 
>     - 	if (ce_stage(ce)) {
>     - 		strbuf_addf(out, _("Skipping unmerged submodule %s"), displaypath);
>      @@ builtin/submodule--helper.c: static int update_submodule(struct update_data *update_data)
>       {
>       	ensure_core_worktree(update_data->sm_path);