Merge pull request libgit2#3882 from pks-t/pks/fix-fetch-refspec-dst-parsing

refspec: do not set empty rhs for fetch refspecs

Author: pks-t

src/refspec.c

@@ -53,8 +53,10 @@ int git_refspec__parse(git_refspec *refspec, const char *input, bool is_fetch)
 
 	if (rhs) {
 		size_t rlen = strlen(++rhs);
-		is_glob = (1 <= rlen && strchr(rhs, '*'));
-		refspec->dst = git__strndup(rhs, rlen);
+		if (rlen || !is_fetch) {
+			is_glob = (1 <= rlen && strchr(rhs, '*'));
+			refspec->dst = git__strndup(rhs, rlen);
+		}
 	}
 
 	llen = (rhs ? (size_t)(rhs - lhs - 1) : strlen(lhs));

tests/online/fetchhead.c

@@ -35,6 +35,19 @@ static void fetchhead_test_clone(void)
 	cl_git_pass(git_clone(&g_repo, LIVE_REPO_URL, "./foo", &g_options));
 }
 
+static int count_references(void)
+{
+	git_strarray array;
+	int refs;
+
+	cl_git_pass(git_reference_list(&array, g_repo));
+	refs = array.count;
+
+	git_strarray_free(&array);
+
+	return refs;
+}
+
 static void fetchhead_test_fetch(const char *fetchspec, const char *expected_fetchhead)
 {
 	git_remote *remote;
@@ -101,3 +114,41 @@ void test_online_fetchhead__no_merges(void)
 	cl_git_pass(git_tag_delete(g_repo, "commit_tree"));
 	fetchhead_test_fetch(NULL, FETCH_HEAD_NO_MERGE_DATA3);
 }
+
+void test_online_fetchhead__explicit_dst_refspec_creates_branch(void)
+{
+	git_reference *ref;
+	int refs;
+
+	fetchhead_test_clone();
+	refs = count_references();
+	fetchhead_test_fetch("refs/heads/first-merge:refs/heads/explicit-refspec", FETCH_HEAD_EXPLICIT_DATA);
+
+	cl_git_pass(git_branch_lookup(&ref, g_repo, "explicit-refspec", GIT_BRANCH_ALL));
+	cl_assert_equal_i(refs + 1, count_references());
+}
+
+void test_online_fetchhead__empty_dst_refspec_creates_no_branch(void)
+{
+	git_reference *ref;
+	int refs;
+
+	fetchhead_test_clone();
+	refs = count_references();
+
+	fetchhead_test_fetch("refs/heads/first-merge", FETCH_HEAD_EXPLICIT_DATA);
+	cl_git_fail(git_branch_lookup(&ref, g_repo, "first-merge", GIT_BRANCH_ALL));
+
+	cl_assert_equal_i(refs, count_references());
+}
+
+void test_online_fetchhead__colon_only_dst_refspec_creates_no_branch(void)
+{
+	int refs;
+
+	fetchhead_test_clone();
+	refs = count_references();
+	fetchhead_test_fetch("refs/heads/first-merge:", FETCH_HEAD_EXPLICIT_DATA);
+
+	cl_assert_equal_i(refs, count_references());
+}