refs: Introduce git_reference_symbolic_create_with_log()

include/git2/refs.h

@@ -98,6 +98,48 @@ GIT_EXTERN(int) git_reference_dwim(git_reference **out, git_repository *repo, co
  */
 GIT_EXTERN(int) git_reference_symbolic_create(git_reference **out, git_repository *repo, const char *name, const char *target, int force);
 
+/**
+ * Create a new symbolic reference and update the reflog with a given
+ * message.
+ *
+ * A symbolic reference is a reference name that refers to another
+ * reference name.  If the other name moves, the symbolic name will move,
+ * too.  As a simple example, the "HEAD" reference might refer to
+ * "refs/heads/master" while on the "master" branch of a repository.
+ *
+ * The symbolic reference will be created in the repository and written to
+ * the disk.  The generated reference object must be freed by the user.
+ *
+ * Valid reference names must follow one of two patterns:
+ *
+ * 1. Top-level names must contain only capital letters and underscores,
+ *    and must begin and end with a letter. (e.g. "HEAD", "ORIG_HEAD").
+ * 2. Names prefixed with "refs/" can be almost anything.  You must avoid
+ *    the characters '~', '^', ':', '\\', '?', '[', and '*', and the
+ *    sequences ".." and "@{" which have special meaning to revparse.
+ *
+ * This function will return an error if a reference already exists with the
+ * given name unless `force` is true, in which case it will be overwritten.
+ *
+ * @param out Pointer to the newly created reference
+ * @param repo Repository where that reference will live
+ * @param name The name of the reference
+ * @param target The target of the reference
+ * @param force Overwrite existing references
+ * @param signature The identity that will used to populate the reflog entry
+ * @param log_message The one line long message that has to be appended
+ * to the reflog
+ * @return 0 on success, EEXISTS, EINVALIDSPEC or an error code
+ */
+GIT_EXTERN(int) git_reference_symbolic_create_with_log(
+	git_reference **out,
+	git_repository *repo,
+	const char *name,
+	const char *target,
+	int force,
+	const git_signature *signature,
+	const char *log_message);
+
 /**
  * Create a new direct reference.
  *

src/refs.c

@@ -465,6 +465,21 @@ int git_reference_symbolic_create(
 	return reference__create(ref_out, repo, name, NULL, target, force, NULL, NULL);
 }
 
+int git_reference_symbolic_create_with_log(
+	git_reference **ref_out,
+	git_repository *repo,
+	const char *name,
+	const char *target,
+	int force,
+	const git_signature *signature,
+	const char* log_message)
+{
+	assert(target && signature && log_message);
+
+	return reference__create(
+		ref_out, repo, name, NULL, target, force, signature, log_message);
+}
+
 int git_reference_set_target(
 	git_reference **out,
 	git_reference *ref,

tests/refs/createwithlog.c

@@ -50,3 +50,34 @@ void test_refs_createwithlog__creating_a_direct_reference_adds_a_reflog_entry(vo
 	git_reference_free(reference);
 	git_signature_free(signature);
 }
+
+void test_refs_createwithlog__creating_a_symbolic_reference_adds_a_reflog_entry(void)
+{
+	git_reference *reference;
+	git_oid id;
+	git_signature *signature;
+	git_reflog *reflog;
+	const git_reflog_entry *entry;
+
+	const char *name = "ANOTHER_HEAD_TRACKER";
+	const char *message = "You've been logged, mate!";
+
+	git_oid_fromstr(&id, current_master_tip);
+
+	cl_git_pass(git_signature_now(&signature, "foo", "foo@bar"));
+
+	cl_git_pass(git_reference_symbolic_create_with_log(&reference, g_repo,
+		name, current_head_target, 0, signature, message));
+
+	cl_git_pass(git_reflog_read(&reflog, reference));
+	cl_assert_equal_sz(1, git_reflog_entrycount(reflog));
+
+	entry = git_reflog_entry_byindex(reflog, 0);
+	cl_assert(git_oid_streq(&entry->oid_old, GIT_OID_HEX_ZERO) == 0);
+	cl_assert(git_oid_cmp(&id, &entry->oid_cur) == 0);
+	cl_assert_equal_s(message, entry->msg);
+
+	git_reflog_free(reflog);
+	git_reference_free(reference);
+	git_signature_free(signature);
+}