Re: [PATCH 2/2] submodule: Try harder to fetch needed sha1 by direct fetching sha1

[Junio C Hamano <gitster@pobox.com>]

Stefan Beller <sbeller@google.com> writes:

> We may want to discuss the error message. It is the same as in the case
> before (git-fetch <no args>), this is good for translation, but may be bad
> for the user as we may want to give extra information.
> ("We fetched for you and it worked, however the sha1 was not included,
> so we fetched again the server broke it, so we error out.  You used to
> see error message: ....")
>
> Although this may be too much information?

Now the "go to that submodule directory and see if $sha1 is
reachable from any of the ref" check is written twice exactly the
same way, it deserves to become a small helper function, I think.

Perhaps something along this line?

 git-submodule.sh | 29 ++++++++++++++++++++++++++---
 1 file changed, 26 insertions(+), 3 deletions(-)

diff --git a/git-submodule.sh b/git-submodule.sh
index 9bc5c5f..836348f 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -591,6 +591,24 @@ cmd_deinit()
 	done
 }
 
+is_tip_reachable () (
+	clear_local_git_env
+	cd "$1" &&
+	rev=$(git rev-list -n 1 "$2" --not --all 2>/dev/null) &&
+	test -z "$rev"
+)
+
+fetch_in_submodule () (
+	clear_local_git_env
+	cd "$1" &&
+	case "$2" in
+	'')
+		git fetch ;;
+	*)
+		git fetch $(get_default_remote) "$2" ;;
+	esac
+)
+
 #
 # Update each submodule path to correct revision, using clone and checkout as needed
 #
@@ -745,9 +763,14 @@ Maybe you want to use 'update --init'?")"
 			then
 				# Run fetch only if $sha1 isn't present or it
 				# is not reachable from a ref.
-				(clear_local_git_env; cd "$sm_path" &&
-					( (rev=$(git rev-list -n 1 $sha1 --not --all 2>/dev/null) &&
-					 test -z "$rev") || git-fetch)) ||
+				is_tip_reachable "$sm_path" "$sha1" ||
+				fetch_in_submodule "$sm_path" ||
+				die "$(eval_gettext "Unable to fetch in submodule path '\$displaypath'")"
+
+				# Now we tried the usual fetch, but $sha1 may
+				# not be reachable from any of the refs
+				is_tip_reachable "$sm_path" "$sha1" ||
+				fetch_in_submodule "$sm_path" "$sha1" ||
 				die "$(eval_gettext "Unable to fetch in submodule path '\$displaypath'")"
 			fi