Commit 6c55fbf37f0548fef0d5d0cdf3eefee26d8a6c04

Patrick Steinhardt 2018-04-06T10:39:16

transports: local: fix assert when fetching into repo with symrefs When fetching into a repository which has symbolic references via the "local" transport we run into an assert. The assert is being triggered while we negotiate the packfile between the two repositories. When hiding known revisions from the packbuilder revwalk, we unconditionally hide all references of the local refdb. In case one of these references is a symbolic reference, though, this means we're trying to hide a `NULL` OID, which triggers the assert. Fix the issue by only hiding OID references from the revwalk. Add a test to catch this issue in the future.

diff --git a/src/transports/local.c b/src/transports/local.c
index 740cf36..0178407 100644
--- a/src/transports/local.c
+++ b/src/transports/local.c
@@ -510,8 +510,12 @@ static int local_counting(int stage, unsigned int current, unsigned int total, v
 static int foreach_reference_cb(git_reference *reference, void *payload)
 {
 	git_revwalk *walk = (git_revwalk *)payload;
+	int error;
+
+	if (git_reference_type(reference) != GIT_REF_OID)
+		return 0;
 
-	int error = git_revwalk_hide(walk, git_reference_target(reference));
+	error = git_revwalk_hide(walk, git_reference_target(reference));
 	/* The reference is in the local repository, so the target may not
 	 * exist on the remote.  It also may not be a commit. */
 	if (error == GIT_ENOTFOUND || error == GITERR_INVALID) {
diff --git a/tests/fetchhead/nonetwork.c b/tests/fetchhead/nonetwork.c
index 4dabb57..a639460 100644
--- a/tests/fetchhead/nonetwork.c
+++ b/tests/fetchhead/nonetwork.c
@@ -343,6 +343,29 @@ void test_fetchhead_nonetwork__unborn_with_upstream(void)
 	cl_fixture_cleanup("./repowithunborn");
 }
 
+void test_fetchhead_nonetwork__fetch_into_repo_with_symrefs(void)
+{
+	git_repository *repo;
+	git_remote *remote;
+	git_reference *symref;
+
+	repo = cl_git_sandbox_init("empty_standard_repo");
+
+	/*
+	 * Testing for a specific constellation where the repository has at
+	 * least one symbolic reference in its refdb.
+	 */
+	cl_git_pass(git_reference_symbolic_create(&symref, repo, "refs/heads/symref", "refs/heads/master", 0, NULL));
+
+	cl_git_pass(git_remote_set_url(repo, "origin", cl_fixture("testrepo.git")));
+	cl_git_pass(git_remote_lookup(&remote, repo, "origin"));
+	cl_git_pass(git_remote_fetch(remote, NULL, NULL, NULL));
+
+	git_remote_free(remote);
+	git_reference_free(symref);
+	cl_git_sandbox_cleanup();
+}
+
 void test_fetchhead_nonetwork__quote_in_branch_name(void)
 {
 	cl_set_cleanup(&cleanup_repository, "./test1");