Re: [PATCH] submodule: no [--merge|--rebase] when newly cloned

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

"Spencer E. Olson" <olsonse@umich.edu> writes:

> Previously, when a submodule was cloned in the same command execution, --rebase
> or --merge would attempt to run (instead of and) before a checkout, resulting in
> an empty working directory.  This patch ignores --rebase or --merge for a
> particular submodule when that submodule is newly cloned and instead simply
> checks out the appropriate revision.

Sorry, but I cannot parse the problem description, "(instead of and)" part.

Why is it a better thing to do to ignore these options, instead of
detecting the situation and error it out, saying "you are initially
cloning, don't say --rebase"?

> +# Test whether an element of the $3(=IFS) separated list $2 matches $1
> +#
> +str_contains()
> +{
> +	if test -n "$3"
> +	then
> +		local IFS="$3"
> +	fi
> +	for i in $2
> +	do
> +		if test "$i" = "$1"
> +		then
> +			echo "yes"
> +			return
> +		fi
> +	done
> +	echo "no"
> +	return
> +}

We don't allow bash-ism outside POSIX shell in our primary Porcelain set
(the rule is looser for stuff in contrib/), so "local" is out.

Here is how to write the above more concisely, efficiently and portably.

	case "$2;" in
        *";$1;"*)
        	echo yes ;;
        *)
        	echo no ;;
	esac

The trailing ';' takes care of the case where cloned_modules has only one
element, in which case you have ";name" in "$2".  No need for a loop.

> +	cloned_modules=
> ...
>  	while read mode sha1 stage path
>  	do
> @@ -442,6 +464,7 @@ cmd_update()
>  		if ! test -d "$path"/.git -o -f "$path"/.git
>  		then
>  			module_clone "$path" "$url" "$reference"|| exit
> +			cloned_modules="$cloned_modules;$name"
>  			subsha1=