Re: Mismatched HEAD default behavior from git log

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

Jeff King <peff@peff.net> writes:

>> As the intent for adding the "--stdin" option to any subcommand has
>> always been "we may need to feed many many things, that may bust the
>> command line length limit, hence we let you feed these things from
>> the standard input, but otherwise there should be no change in
>> behaviour or semantics", when the behaviour of command line and
>> "--stdin" differ, it is a bug in the latter.
>
> Agreed. It also helps in this case that the command-line behavior is
> sensible and the --stdin one is not. :)
>
> I think the solution is probably something like:

You beat me to it while I was wondering what to do between the local
got_rev_arg variable and the revs->rev_input_given field.


> diff --git a/revision.c b/revision.c
> index 96630e3186..f5bbefa091 100644
> --- a/revision.c
> +++ b/revision.c
> @@ -2099,12 +2099,13 @@ static void read_pathspec_from_stdin(struct strbuf *sb,
>  		strvec_push(prune, sb->buf);
>  }
>  
> -static void read_revisions_from_stdin(struct rev_info *revs,
> -				      struct strvec *prune)
> +static int read_revisions_from_stdin(struct rev_info *revs,
> +				     struct strvec *prune)
>  {
>  	struct strbuf sb;
>  	int seen_dashdash = 0;
>  	int save_warning;
> +	int got_rev_arg = 0;
>  
>  	save_warning = warn_on_object_refname_ambiguity;
>  	warn_on_object_refname_ambiguity = 0;
> @@ -2124,12 +2125,14 @@ static void read_revisions_from_stdin(struct rev_info *revs,
>  		if (handle_revision_arg(sb.buf, revs, 0,
>  					REVARG_CANNOT_BE_FILENAME))
>  			die("bad revision '%s'", sb.buf);
> +		got_rev_arg = 1;
>  	}
>  	if (seen_dashdash)
>  		read_pathspec_from_stdin(&sb, prune);
>  
>  	strbuf_release(&sb);
>  	warn_on_object_refname_ambiguity = save_warning;
> +	return got_rev_arg;
>  }
>  
>  static void add_grep(struct rev_info *revs, const char *ptn, enum grep_pat_token what)
> @@ -2754,7 +2757,8 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s
>  				}
>  				if (revs->read_from_stdin++)
>  					die("--stdin given twice?");
> -				read_revisions_from_stdin(revs, &prune_data);
> +				if (read_revisions_from_stdin(revs, &prune_data))
> +					got_rev_arg = 1;
>  				continue;
>  			}
>  
>
> Possibly it would make sense to push that flag into rev_info, though,
> and let handle_revision_arg() set it. That would fix this bug and
> prevent similar ones in other code paths (though we're not likely to get
> revisions from anywhere else, I suppose).
>
> -Peff