Re: [PATCH 2/3] doc-diff: add --clean mode to remove temporary working gunk

[Jeff King <peff@peff.net>]

On Fri, Aug 31, 2018 at 02:33:17AM -0400, Eric Sunshine wrote:

> As part of its operation, doc-diff creates a bunch of temporary
> working files and holds onto them in order to speed up subsequent
> invocations. These files are never deleted. Moreover, it creates a
> temporary working tree (via git-wortkree) which likewise never gets
> removed.
> 
> Without knowing the implementation details of the tool, a user may not
> know how to clean up manually afterward. Worse, the user may find it
> surprising and alarming to discover a working tree which s/he did not
> create explicitly.
> 
> To address these issues, add a --clean mode which removes the
> temporary working tree and deletes all generated files.

That sounds like a good plan. I like keeping the complexity here in the
script.

> diff --git a/Documentation/doc-diff b/Documentation/doc-diff
> index c2906eac5e..f397fd229b 100755
> --- a/Documentation/doc-diff
> +++ b/Documentation/doc-diff
> @@ -2,20 +2,25 @@
>  
>  OPTIONS_SPEC="\
>  doc-diff [options] <from> <to> [-- <diff-options>]
> +doc-diff (-c|--clean)
>  --
>  j=n	parallel argument to pass to make
>  f	force rebuild; do not rely on cached results
> +c,clean	cleanup temporary working files
>  "

This will cause parseopt to normalize "--clean" to "-c" (along with
"--cle", etc).

>  parallel=
>  force=
> +clean=
>  while test $# -gt 0
>  do
>  	case "$1" in
>  	-j)
>  		parallel=$2; shift ;;
> +	-c|--clean)
> +		clean=t ;;

So this part can just test for "-c". AFAICT this is how "rev-parse
--parseopt" has always worked, though the documentation is quite
unclear. Other scripts seem to also use these redundant long options.
I'm not opposed to including it as a defensive measure (or simply an
annotation for the reader).

> +cd_to_toplevel
> +tmp=Documentation/tmp-doc-diff
> +
> +if test -n "$clean"
> +then
> +	test $# -eq 0 || usage
> +	git worktree remove --force "$tmp/worktree" 2>/dev/null
> +	rm -rf "$tmp"
> +	exit 0
> +fi

And this matches what I'd expect "--clean" to do. Makes sense.

-Peff