Re: [PATCH 17/19] submodule: use submodule repos for object lookup

On Thu, Oct 11, 2018 at 3:41 PM Jonathan Tan [off-list ref] wrote:

quoted

+/*
+ * Initialize 'out' based on the provided submodule path.
+ *
+ * Unlike repo_submodule_init, this tolerates submodules not present
+ * in .gitmodules. NEEDSWORK: The repo_submodule_init behavior is
+ * preferrable. This function exists only to preserve historical behavior.

What do you mean by "The repo_submodule_init behavior is preferable"? If
we need to preserve historical behavior, then it seems that the most
preferable one is something that meets our needs (like open_submodule()
in this patch).

quoted

+static int open_submodule(struct repository *out, const char *path)
+{
+     struct strbuf sb = STRBUF_INIT;
+
+     if (submodule_to_gitdir(&sb, path) || repo_init(out, sb.buf, NULL)) {
+             strbuf_release(&sb);
+             return -1;
+     }
+
+     out->submodule_prefix = xstrdup(path);

Do we need to set submodule_prefix?

quoted

@@ -507,7 +533,7 @@ static void show_submodule_header(struct diff_options *o, const char *path,
      else if (is_null_oid(two))
              message = "(submodule deleted)";

-     if (add_submodule_odb(path)) {
+     if (open_submodule(sub, path) < 0) {

This function, as a side effect, writes the open repository to "sub" for
its caller to use. I think it's better if its callers open "sub" and
then pass it to show_submodule_header() if successful. If opening the
submodule is expected to fail sometimes (like it seems here), then we
can allow callers to also pass NULL, and document what happens when NULL
is passed.

Thanks for the review of the whole series!

I have redone this series, addressing all your comments. I addressed
this comment differently than suggested, and put the submodule
repository argument at the end of the parameter list, such that it
goes with all the other arguments to be filled in.

I was about to resend the series, but test-merged with the other
submodule series in flight (origin/sb/submodule-recursive-fetch-gets-the-tip)
which had some conflicts that I can easily resolve by rebasing on top.

It conflicts a lot when merging to next, due to the latest patch
("Apply semantic patches from previous patches"), so I am not sure
how to proceed properly. Maybe we'd omit that patch and
run 'make coccicheck' on next to apply the semantic patches
there instead.