Subject: Re: [PATCH v2 13/16] ref-filter: add --no-contains option to tag/branch/for-each-ref

From: Junio C Hamano <[email-masked]>
Date: Tue, 21 Mar 2017 11:51:57 -0700

Ævar Arnfjörð Bjarmason  <[email-masked]> writes:

> Change the tag, branch & for-each-ref commands to have a --no-contains
> option in addition to their longstanding --contains options.
>
> This allows for finding the last-good rollout tag given a known-bad
> <commit>. Given a hypothetically bad commit cf5c7253e0, the git
> version to revert to can be found with this hacky two-liner:
>
>     (git tag -l 'v[0-9]*'; git tag -l --contains cf5c7253e0 'v[0-9]*') |
>         sort | uniq -c | grep -E '^ *1 ' | awk '{print $2}' | tail -n 10
>
> With this new --no-contains option the same can be achieved with:
>
>     git tag -l --no-contains cf5c7253e0 'v[0-9]*' | sort | tail -n 10
>
> As the filtering machinery is shared between the tag, branch &
> for-each-ref commands, implement this for those commands too. A
> practical use for this with "branch" is e.g. finding branches which
> were branched off between v2.8.0 and v2.10.0:
>
>     git branch --contains v2.8.0 --no-contains v2.10.0
>
> The "describe" command also has a --contains option, but its semantics
> are unrelated to what tag/branch/for-each-ref use --contains for. A
> --no-contains option for "describe" wouldn't make any sense, other
> than being exactly equivalent to not supplying --contains at all,
> which would be confusing at best.

Nicely explained.  Thanks.

> diff --git a/parse-options.h b/parse-options.h
> index dcd8a0926c..0eac90b510 100644
> --- a/parse-options.h
> +++ b/parse-options.h
> @@ -258,7 +258,9 @@ extern int parse_opt_passthru_argv(const struct option *, const char *, int);
>  	  PARSE_OPT_LASTARG_DEFAULT | flag, \
>  	  parse_opt_commits, (intptr_t) "HEAD" \
>  	}
> -#define OPT_CONTAINS(v, h) _OPT_CONTAINS_OR_WITH("contains", v, h, 0)
> +#define OPT_CONTAINS(v, h) _OPT_CONTAINS_OR_WITH("contains", v, h, PARSE_OPT_NONEG)
> +#define OPT_NO_CONTAINS(v, h) _OPT_CONTAINS_OR_WITH("no-contains", v, h, PARSE_OPT_NONEG)
>  #define OPT_WITH(v, h) _OPT_CONTAINS_OR_WITH("with", v, h, PARSE_OPT_HIDDEN)
> +#define OPT_WITHOUT(v, h) _OPT_CONTAINS_OR_WITH("without", v, h, PARSE_OPT_HIDDEN)

Doesn't OPT_WITHOUT() need PARSE_OPT_NONEG (in addition to HIDDEN),
just like OPT_NO_CONTAINS() uses one to reject "--no-no-contains"?
Does the code do a sensible thing when --no-without is given?