parse-options: don't emit "ambiguous option" for aliases
Change the option parsing machinery so that e.g. "clone --recurs ..."
doesn't error out because "clone" understands both "--recursive" and
"--recurse-submodules" to mean the same thing.
Initially "clone" just understood --recursive until the
--recurses-submodules alias was added in ccdd3da652 ("clone: Add the
--recurse-submodules option as alias for --recursive",
2010-11-04). Since bb62e0a99f ("clone: teach --recurse-submodules to
optionally take a pathspec", 2017-03-17) the longer form has been
promoted to the default.
But due to the way the options parsing machinery works this resulted
in the rather absurd situation of:
$ git clone --recurs [...]
error: ambiguous option: recurs (could be --recursive or --recurse-submodules)
Add OPT_ALIAS() to express this link between two or more options and use
it in git-clone. Multiple aliases of an option could be written as
OPT_ALIAS(0, "alias1", "original-name"),
OPT_ALIAS(0, "alias2", "original-name"),
...
The current implementation is not exactly optimal in this case. But we
can optimize it when it becomes a problem. So far we don't even have two
aliases of any option.
A big chunk of code is actually from Junio C Hamano.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/parse-options.c b/parse-options.c
index cb24f1a..987e27c 100644
--- a/parse-options.c
+++ b/parse-options.c
@@ -261,6 +261,35 @@ static enum parse_opt_result parse_short_opt(struct parse_opt_ctx_t *p,
return PARSE_OPT_UNKNOWN;
}
+static int has_string(const char *it, const char **array)
+{
+ while (*array)
+ if (!strcmp(it, *(array++)))
+ return 1;
+ return 0;
+}
+
+static int is_alias(struct parse_opt_ctx_t *ctx,
+ const struct option *one_opt,
+ const struct option *another_opt)
+{
+ const char **group;
+
+ if (!ctx->alias_groups)
+ return 0;
+
+ if (!one_opt->long_name || !another_opt->long_name)
+ return 0;
+
+ for (group = ctx->alias_groups; *group; group += 3) {
+ /* it and other are from the same family? */
+ if (has_string(one_opt->long_name, group) &&
+ has_string(another_opt->long_name, group))
+ return 1;
+ }
+ return 0;
+}
+
static enum parse_opt_result parse_long_opt(
struct parse_opt_ctx_t *p, const char *arg,
const struct option *options)
@@ -298,7 +327,8 @@ static enum parse_opt_result parse_long_opt(
if (!(p->flags & PARSE_OPT_KEEP_UNKNOWN) &&
!strncmp(long_name, arg, arg_end - arg)) {
is_abbreviated:
- if (abbrev_option) {
+ if (abbrev_option &&
+ !is_alias(p, abbrev_option, options)) {
/*
* If this is abbreviated, it is
* ambiguous. So when there is no
@@ -447,6 +477,10 @@ static void parse_options_check(const struct option *opts)
if (opts->callback)
BUG("OPTION_LOWLEVEL_CALLBACK needs no high level callback");
break;
+ case OPTION_ALIAS:
+ BUG("OPT_ALIAS() should not remain at this point. "
+ "Are you using parse_options_step() directly?\n"
+ "That case is not supported yet.");
default:
; /* ok. (usually accepts an argument) */
}
@@ -458,11 +492,10 @@ static void parse_options_check(const struct option *opts)
exit(128);
}
-void parse_options_start(struct parse_opt_ctx_t *ctx,
- int argc, const char **argv, const char *prefix,
- const struct option *options, int flags)
+static void parse_options_start_1(struct parse_opt_ctx_t *ctx,
+ int argc, const char **argv, const char *prefix,
+ const struct option *options, int flags)
{
- memset(ctx, 0, sizeof(*ctx));
ctx->argc = argc;
ctx->argv = argv;
if (!(flags & PARSE_OPT_ONE_SHOT)) {
@@ -484,6 +517,14 @@ void parse_options_start(struct parse_opt_ctx_t *ctx,
parse_options_check(options);
}
+void parse_options_start(struct parse_opt_ctx_t *ctx,
+ int argc, const char **argv, const char *prefix,
+ const struct option *options, int flags)
+{
+ memset(ctx, 0, sizeof(*ctx));
+ parse_options_start_1(ctx, argc, argv, prefix, options, flags);
+}
+
static void show_negated_gitcomp(const struct option *opts, int nr_noopts)
{
int printed_dashdash = 0;
@@ -575,6 +616,83 @@ static int show_gitcomp(const struct option *opts)
return PARSE_OPT_COMPLETE;
}
+/*
+ * Scan and may produce a new option[] array, which should be used
+ * instead of the original 'options'.
+ *
+ * Right now this is only used to preprocess and substitue
+ * OPTION_ALIAS.
+ */
+static struct option *preprocess_options(struct parse_opt_ctx_t *ctx,
+ const struct option *options)
+{
+ struct option *newopt;
+ int i, nr, alias;
+ int nr_aliases = 0;
+
+ for (nr = 0; options[nr].type != OPTION_END; nr++) {
+ if (options[nr].type == OPTION_ALIAS)
+ nr_aliases++;
+ }
+
+ if (!nr_aliases)
+ return NULL;
+
+ ALLOC_ARRAY(newopt, nr + 1);
+ COPY_ARRAY(newopt, options, nr + 1);
+
+ /* each alias has two string pointers and NULL */
+ CALLOC_ARRAY(ctx->alias_groups, 3 * (nr_aliases + 1));
+
+ for (alias = 0, i = 0; i < nr; i++) {
+ int short_name;
+ const char *long_name;
+ const char *source;
+ int j;
+
+ if (newopt[i].type != OPTION_ALIAS)
+ continue;
+
+ short_name = newopt[i].short_name;
+ long_name = newopt[i].long_name;
+ source = newopt[i].value;
+
+ if (!long_name)
+ BUG("An alias must have long option name");
+
+ for (j = 0; j < nr; j++) {
+ const char *name = options[j].long_name;
+
+ if (!name || strcmp(name, source))
+ continue;
+
+ if (options[j].type == OPTION_ALIAS)
+ BUG("No please. Nested aliases are not supported.");
+
+ /*
+ * NEEDSWORK: this is a bit inconsistent because
+ * usage_with_options() on the original options[] will print
+ * help string as "alias of %s" but "git cmd -h" will
+ * print the original help string.
+ */
+ memcpy(newopt + i, options + j, sizeof(*newopt));
+ newopt[i].short_name = short_name;
+ newopt[i].long_name = long_name;
+ break;
+ }
+
+ if (j == nr)
+ BUG("could not find source option '%s' of alias '%s'",
+ source, newopt[i].long_name);
+ ctx->alias_groups[alias * 3 + 0] = newopt[i].long_name;
+ ctx->alias_groups[alias * 3 + 1] = options[j].long_name;
+ ctx->alias_groups[alias * 3 + 2] = NULL;
+ alias++;
+ }
+
+ return newopt;
+}
+
static int usage_with_options_internal(struct parse_opt_ctx_t *,
const char * const *,
const struct option *, int, int);
@@ -714,11 +832,16 @@ int parse_options(int argc, const char **argv, const char *prefix,
int flags)
{
struct parse_opt_ctx_t ctx;
+ struct option *real_options;
disallow_abbreviated_options =
git_env_bool("GIT_TEST_DISALLOW_ABBREVIATED_OPTIONS", 0);
- parse_options_start(&ctx, argc, argv, prefix, options, flags);
+ memset(&ctx, 0, sizeof(ctx));
+ real_options = preprocess_options(&ctx, options);
+ if (real_options)
+ options = real_options;
+ parse_options_start_1(&ctx, argc, argv, prefix, options, flags);
switch (parse_options_step(&ctx, options, usagestr)) {
case PARSE_OPT_HELP:
case PARSE_OPT_ERROR:
@@ -741,6 +864,8 @@ int parse_options(int argc, const char **argv, const char *prefix,
}
precompose_argv(argc, argv);
+ free(real_options);
+ free(ctx.alias_groups);
return parse_options_end(&ctx);
}
@@ -835,6 +960,12 @@ static int usage_with_options_internal(struct parse_opt_ctx_t *ctx,
fputc('\n', outfile);
pad = USAGE_OPTS_WIDTH;
}
+ if (opts->type == OPTION_ALIAS) {
+ fprintf(outfile, "%*s", pad + USAGE_GAP, "");
+ fprintf_ln(outfile, _("alias of --%s"),
+ (const char *)opts->value);
+ continue;
+ }
fprintf(outfile, "%*s%s\n", pad + USAGE_GAP, "", _(opts->help));
}
fputc('\n', outfile);
