Subject: [PATCH v4 5/9] parse-options: parse into strvec

From: Emily Shaffer <[email-masked]>
Date: Tue, 8 Sep 2020 17:49:35 -0700

parse-options already knows how to read into a string_list, and it knows
how to read into an strvec as a passthrough (that is, including the
argument as well as its value). string_list and strvec serve similar
purposes but are somewhat painful to convert between; so, let's teach
parse-options to read values of string arguments directly into an
strvec without preserving the argument name.

This is useful if collecting generic arguments to pass through to
another command, for example, 'git hook run --arg "--quiet" --arg
"--format=pretty" some-hook'. The resulting strvec would contain
{ "--quiet", "--format=pretty" }.

The implementation is based on that of OPT_STRING_LIST.

Signed-off-by: Emily Shaffer <[email-masked]>
---
 Documentation/technical/api-parse-options.txt |  5 +++++
 parse-options-cb.c                            | 16 ++++++++++++++++
 parse-options.h                               |  4 ++++
 3 files changed, 25 insertions(+)

diff --git a/Documentation/technical/api-parse-options.txt b/Documentation/technical/api-parse-options.txt
index 5a60bbfa7f..b4f1fc4a1a 100644
--- a/Documentation/technical/api-parse-options.txt
+++ b/Documentation/technical/api-parse-options.txt
@@ -173,6 +173,11 @@ There are some macros to easily define options:
 	The string argument is stored as an element in `string_list`.
 	Use of `--no-option` will clear the list of preceding values.
 
+`OPT_ARGV_ARRAY(short, long, &struct argv_array, arg_str, description)`::
+	Introduce an option with a string argument.
+	The string argument is stored as an element in `argv_array`.
+	Use of `--no-option` will clear the list of preceding values.
+
 `OPT_INTEGER(short, long, &int_var, description)`::
 	Introduce an option with integer argument.
 	The integer is put into `int_var`.
diff --git a/parse-options-cb.c b/parse-options-cb.c
index d9d3b0819f..d2b8b7b98a 100644
--- a/parse-options-cb.c
+++ b/parse-options-cb.c
@@ -205,6 +205,22 @@ int parse_opt_string_list(const struct option *opt, const char *arg, int unset)
 	return 0;
 }
 
+int parse_opt_strvec(const struct option *opt, const char *arg, int unset)
+{
+	struct strvec *v = opt->value;
+
+	if (unset) {
+		strvec_clear(v);
+		return 0;
+	}
+
+	if (!arg)
+		return -1;
+
+	strvec_push(v, arg);
+	return 0;
+}
+
 int parse_opt_noop_cb(const struct option *opt, const char *arg, int unset)
 {
 	return 0;
diff --git a/parse-options.h b/parse-options.h
index 46af942093..177259488b 100644
--- a/parse-options.h
+++ b/parse-options.h
@@ -177,6 +177,9 @@ struct option {
 #define OPT_STRING_LIST(s, l, v, a, h) \
 				    { OPTION_CALLBACK, (s), (l), (v), (a), \
 				      (h), 0, &parse_opt_string_list }
+#define OPT_STRVEC(s, l, v, a, h) \
+				    { OPTION_CALLBACK, (s), (l), (v), (a), \
+				      (h), 0, &parse_opt_strvec }
 #define OPT_UYN(s, l, v, h)         { OPTION_CALLBACK, (s), (l), (v), NULL, \
 				      (h), PARSE_OPT_NOARG, &parse_opt_tertiary }
 #define OPT_EXPIRY_DATE(s, l, v, h) \
@@ -296,6 +299,7 @@ int parse_opt_commits(const struct option *, const char *, int);
 int parse_opt_commit(const struct option *, const char *, int);
 int parse_opt_tertiary(const struct option *, const char *, int);
 int parse_opt_string_list(const struct option *, const char *, int);
+int parse_opt_strvec(const struct option *, const char *, int);
 int parse_opt_noop_cb(const struct option *, const char *, int);
 enum parse_opt_result parse_opt_unknown_cb(struct parse_opt_ctx_t *ctx,
 					   const struct option *,
-- 
2.28.0.rc0.142.g3c755180ce-goog