Jeff King <peff@xxxxxxxx> writes:
> This is a fix on top of ab/retire-parse-remote, which is now in next. I
> think submodule fetching is pretty broken, so we should do this or
> something like it soon.
>
> -- >8 --
> Commit 1c1518071c (submodule: use "fetch" logic instead of custom remote
> discovery, 2020-11-14) rewrote the logic in fetch_in_submodule to do:
>
> elif test "$2" -ne ""
>
> But this is nonsense in shell: -ne is for numeric comparisons. This
> should be "=" or more idiomatically:
>
> elif test -n "$2"
>
> But once we fix that, many tests start failing. Because that commit
> introduced another problem. The caller that passes 3 arguments looks
> like this:
>
> fetch_in_submodule "$sm_path" $depth "$sha1"
>
> Note the unquoted $depth parameter. When it isn't set, the function will
> see only 2 arguments, and the function has no idea if what it sees in $2
> is an option to go on the command line, or a refspec to pass on stdin.
> In the old code before that commit:
>
> fetch_in_submodule () (
> sanitize_submodule_env &&
> cd "$1" &&
> - case "$2" in
> - '')
> - git fetch ;;
> - *)
> - shift
> - git fetch $(get_default_remote) "$@" ;;
> - esac
>
> we treated those the same, so it didn't matter. But in the new logic
> (with my fix above):
>
> + if test $# -eq 3
> + then
> + echo "$3" | git fetch --stdin "$2"
> + elif test -n "$n"
> + then
> + git fetch "$2"
> + else
> + git fetch
> + fi
>
> we use the number of parameters to distinguish the two. Let's insist
> that the caller pass an empty string for positional parameter two if
> they want to have a third parameter after it.
Thanks for catching. I thought we stared at this part long enough
to be updated between the rounds; it is embarrassing that we've
missed it.
> - it probably wouldn't hurt to beef up the tests, especially around
> fetching an unreachable sha1, but after getting lost for an hour in
> the spaghetti of the submodule code and its tests, I gave up. I do
> at least feel this code is being exercised (because once the initial
> problem is fixed, tons of things fail).
True.
> +# usage: fetch_in_submodule <module_path> [<depth>] [<sha1>]
> +# Because arguments are positional, use an empty string to omit <depth>
> +# but include <sha1>.
> fetch_in_submodule () (
> sanitize_submodule_env &&
> cd "$1" &&
> if test $# -eq 3
> then
> - echo "$3" | git fetch --stdin "$2"
> - elif test "$2" -ne ""
> - then
> - git fetch "$2"
> + echo "$3" | git fetch --stdin ${2:+"$2"}
> else
> - git fetch
> + git fetch ${2:+"$2"}
> fi
> )
Makes sense. Thanks.
> @@ -603,7 +603,7 @@ cmd_update()
> # 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" $depth "$sha1" ||
> + fetch_in_submodule "$sm_path" "$depth" "$sha1" ||
> die "$(eval_gettext "Fetched in submodule path '\$displaypath', but it did not contain \$sha1. Direct fetching of that commit failed.")"
> fi
