Jeff King <peff@xxxxxxxx> writes:
> If revs->def is set (as it is in "git log") and there are no
> pending objects after parsing the user's input, then we show
> whatever is in "def". But if the user _did_ ask for some
> input that just happened to be empty (e.g., "--glob" that
> does not match anything), showing the default revision is
> confusing. We should just show nothing, as that is what the
> user's request yielded.
>
> Signed-off-by: Jeff King <peff@xxxxxxxx>
> ---
> The "!got_rev_arg" that's already in the conditional is interesting. I
> wondered if it could be subsumed by the rev_input_given flag. But
> digging in the history, I think it's mostly about doing reflog walks.
> Usually if we see a rev arg it will result either in an object added to
> the pending queue, or a fatal error. But empty reflogs are the
> exception. And since my other nearby series adds a separate check for
> "are we doing an empty reflog walk", I don't think it makes sense to
> tangle this up the new flag I'm adding here.
OK, I'll have to stare at possible merge conflicts to see if I like
this or some other design decision ;-)
This shows one of the reasons why I want consumers of revision
machinery not to be futzing these internal implementation detail
bits in the revs structure, by the way.
> revision.c | 2 +-
> t/t4202-log.sh | 6 ++++++
> 2 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/revision.c b/revision.c
> index 08d5806b8..ba2b166cd 100644
> --- a/revision.c
> +++ b/revision.c
> @@ -2316,7 +2316,7 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s
> opt->tweak(revs, opt);
> if (revs->show_merge)
> prepare_show_merge(revs);
> - if (revs->def && !revs->pending.nr && !got_rev_arg) {
> + if (revs->def && !revs->pending.nr && !revs->rev_input_given && !got_rev_arg) {
> struct object_id oid;
> struct object *object;
> struct object_context oc;
> diff --git a/t/t4202-log.sh b/t/t4202-log.sh
> index 3f3531f0a..36d120c96 100755
> --- a/t/t4202-log.sh
> +++ b/t/t4202-log.sh
> @@ -1523,6 +1523,12 @@ test_expect_success 'log diagnoses bogus HEAD' '
> test_i18ngrep broken stderr
> '
>
> +test_expect_success 'log does not default to HEAD when rev input is given' '
> + >expect &&
> + git log --branches=does-not-exist >actual &&
> + test_cmp expect actual
> +'
> +
> test_expect_success 'set up --source tests' '
> git checkout --orphan source-a &&
> test_commit one &&
