[PATCH 6/7] parse-options: have a `use default value` wildcard.

[Pierre Habouzit <madcoder@debian.org>]

Signed-off-by: Pierre Habouzit <madcoder@debian.org>
---
 Documentation/gitcli.txt |   20 +++++++++++++++-----
 parse-options.c          |   10 ++++++++--
 2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/Documentation/gitcli.txt b/Documentation/gitcli.txt
index b7dcf9c..a304072 100644
--- a/Documentation/gitcli.txt
+++ b/Documentation/gitcli.txt
@@ -95,14 +95,24 @@ $ git foo -oArg
 $ git foo -o Arg
 ----------------------------
 
-However, this is *NOT* allowed for switches with an optionnal value, where the
-'sticked' form must be used:
+However, this may become ambiguous for switches with an optional value. The
+enhanced option parser provides a placeholder `{}` that tells to the option
+parser that it should not try to find an argument to this switch.  Though if
+you use '{}' sticked to the option, `{}` is passed as the value.
 ----------------------------
-$ git describe --abbrev HEAD     # correct
-$ git describe --abbrev=10 HEAD  # correct
-$ git describe --abbrev 10 HEAD  # NOT WHAT YOU MEANT
+# all the following uses work
+$ git describe --abbrev HEAD
+$ git describe --abbrev {} HEAD
+$ git describe --abbrev=10 HEAD
+$ git describe --abbrev 10 HEAD
+
+# doesn't work
+$ git describe --abbrev={} HEAD
 ----------------------------
 
+Note that an optional switch will never try to use the next token as an
+argument if it starts with a dash and is not `-`.
+
 
 Documentation
 -------------
diff --git a/parse-options.c b/parse-options.c
index 679a963..8734bb1 100644
--- a/parse-options.c
+++ b/parse-options.c
@@ -69,8 +69,14 @@ static int run_callback(struct optparse_t *p, parse_opt_cb *cb,
 		return (*cb)(opt, NULL, flags);
 	if (!may_ign && !arg)
 		return opterror(opt, "requires a value", flags);
-	if (may_ign && arg && arg[0] == '-' && arg[1])
-		return (*cb)(opt, NULL, flags);
+	if (may_ign && arg) {
+		if (arg[0] == '-' && arg[1])
+			return (*cb)(opt, NULL, flags);
+		if (!strcmp(arg, "{}")) {
+			use_arg(p);
+			return (*cb)(opt, NULL, flags);
+		}
+	}
 	switch ((*cb)(opt, arg, flags | may_ign)) {
 	case PARSE_OPT_OK:
 		use_arg(p);
-- 
1.5.4.rc0.1148.ga3ab1-dirty