1 files changed, 67 insertions, 19 deletions

diff --git a/refspec.c b/refspec.c
index 8d0affc..d60932f 100644
--- a/refspec.c
+++ b/refspec.c
@@ -1,15 +1,20 @@
-#include "cache.h"
+#include "git-compat-util.h"
+#include "gettext.h"
+#include "hash.h"
+#include "hex.h"
 #include "strvec.h"
 #include "refs.h"
 #include "refspec.h"
+#include "strbuf.h"
 
 static struct refspec_item s_tag_refspec = {
-	0,
-	1,
-	0,
-	0,
-	"refs/tags/*",
-	"refs/tags/*"
+	.force = 0,
+	.pattern = 1,
+	.matching = 0,
+	.exact_sha1 = 0,
+	.negative = 0,
+	.src = "refs/tags/*",
+	.dst = "refs/tags/*",
 };
 
 /* See TAG_REFSPEC for the string version */
@@ -32,10 +37,17 @@ static int parse_refspec(struct refspec_item *item, const char *refspec, int fet
 	if (*lhs == '+') {
 		item->force = 1;
 		lhs++;
+	} else if (*lhs == '^') {
+		item->negative = 1;
+		lhs++;
 	}
 
 	rhs = strrchr(lhs, ':');
 
+	/* negative refspecs only have one side */
+	if (item->negative && rhs)
+		return 0;
+
 	/*
 	 * Before going on, special case ":" (or "+:") as a refspec
 	 * for pushing matching refs.
@@ -55,7 +67,7 @@ static int parse_refspec(struct refspec_item *item, const char *refspec, int fet
 
 	llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
 	if (1 <= llen && memchr(lhs, '*', llen)) {
-		if ((rhs && !is_glob) || (!rhs && fetch))
+		if ((rhs && !is_glob) || (!rhs && !item->negative && fetch))
 			return 0;
 		is_glob = 1;
 	} else if (rhs && is_glob) {
@@ -63,9 +75,34 @@ static int parse_refspec(struct refspec_item *item, const char *refspec, int fet
 	}
 
 	item->pattern = is_glob;
-	item->src = xstrndup(lhs, llen);
+	if (llen == 1 && *lhs == '@')
+		item->src = xstrdup("HEAD");
+	else
+		item->src = xstrndup(lhs, llen);
 	flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 
+	if (item->negative) {
+		struct object_id unused;
+
+		/*
+		 * Negative refspecs only have a LHS, which indicates a ref
+		 * (or pattern of refs) to exclude from other matches. This
+		 * can either be a simple ref, or a glob pattern. Exact sha1
+		 * match is not currently supported.
+		 */
+		if (!*item->src)
+			return 0; /* negative refspecs must not be empty */
+		else if (llen == the_hash_algo->hexsz && !get_oid_hex(item->src, &unused))
+			return 0; /* negative refpsecs cannot be exact sha1 */
+		else if (!check_refname_format(item->src, flags))
+			; /* valid looking ref is ok */
+		else
+			return 0;
+
+		/* the other rules below do not apply to negative refspecs */
+		return 1;
+	}
+
 	if (fetch) {
 		struct object_id unused;
 
@@ -215,6 +252,16 @@ int valid_fetch_refspec(const char *fetch_refspec_str)
 	return ret;
 }
 
+int valid_remote_name(const char *name)
+{
+	int result;
+	struct strbuf refspec = STRBUF_INIT;
+	strbuf_addf(&refspec, "refs/heads/test:refs/remotes/%s/test", name);
+	result = valid_fetch_refspec(refspec.buf);
+	strbuf_release(&refspec);
+	return result;
+}
+
 void refspec_ref_prefixes(const struct refspec *rs,
 			  struct strvec *ref_prefixes)
 {
@@ -223,7 +270,7 @@ void refspec_ref_prefixes(const struct refspec *rs,
 		const struct refspec_item *item = &rs->items[i];
 		const char *prefix = NULL;
 
-		if (item->exact_sha1)
+		if (item->exact_sha1 || item->negative)
 			continue;
 		if (rs->fetch == REFSPEC_FETCH)
 			prefix = item->src;
@@ -232,15 +279,16 @@ void refspec_ref_prefixes(const struct refspec *rs,
 		else if (item->src && !item->exact_sha1)
 			prefix = item->src;
 
-		if (prefix) {
-			if (item->pattern) {
-				const char *glob = strchr(prefix, '*');
-				strvec_pushf(ref_prefixes, "%.*s",
-					     (int)(glob - prefix),
-					     prefix);
-			} else {
-				expand_ref_prefix(ref_prefixes, prefix);
-			}
+		if (!prefix)
+			continue;
+
+		if (item->pattern) {
+			const char *glob = strchr(prefix, '*');
+			strvec_pushf(ref_prefixes, "%.*s",
+				     (int)(glob - prefix),
+				     prefix);
+		} else {
+			expand_ref_prefix(ref_prefixes, prefix);
 		}
 	}
 }