On Sat, Jan 20, 2024 at 03:39:38PM +0100, René Scharfe wrote:
> > The issue is that we have "--rename-empty", which of course also
> > provides "--no-rename-empty". And parse-options is happy to let you
> > abbreviate names as long as they are unambiguous. But "--no-rename" _is_
> > ambiguous with "--no-renames". Why don't we catch it?
>
> Because diff_opt_parse() passes PARSE_OPT_KEEP_UNKNOWN_OPT, which makes
> parse_long_opt() skip abbreviation detection. Which it does since
> baa4adc66a (parse-options: disable option abbreviation with
> PARSE_OPT_KEEP_UNKNOWN, 2019-01-27).
OK, it makes sense to me that we should avoid abbreviation entirely with
KEEP_UNKNOWN_OPT, for the reasons given in that commit. But if adding
--rename fixed it, is there another bug lurking? That is, would we do
the wrong thing on a case without KEEP_UNKNOWN_OPT but which had
"--renames" and "--no-rename" defined? Or was it simply the
inconsistency in how KEEP_UNKNOWN_OPT is being applied?
I think it might just be the latter. If I do this:
diff --git a/t/helper/test-parse-options.c b/t/helper/test-parse-options.c
index ded8116cc5..e908c7386d 100644
--- a/t/helper/test-parse-options.c
+++ b/t/helper/test-parse-options.c
@@ -124,6 +124,7 @@ int cmd__parse_options(int argc, const char **argv)
struct option options[] = {
OPT_BOOL(0, "yes", &boolean, "get a boolean"),
OPT_BOOL('D', "no-doubt", &boolean, "begins with 'no-'"),
+ OPT_BOOL(0, "do-it", &boolean, "'do' ambiguous with 'doubt'"),
{ OPTION_SET_INT, 'B', "no-fear", &boolean, NULL,
"be brave", PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL, 1 },
OPT_COUNTUP('b', "boolean", &boolean, "increment by one"),
then running:
t/helper/test-tool parse-options --do
correctly complains about the ambiguity (though amusingly it mentions
"--no-no-doubt" in the error message). And if I add KEEP_UNKNOWN_OPT,
then it gives the wrong behavior. But curiously it does so even with
your patch applied. So I think there may be further fixes needed.
-Peff
