Re: [PATCH v2 05/19] pull: implement fetch + merge

Paul Tan [off-list ref] writes:

+/**
+ * Parses argv into [<repo> [<refspecs>...]], returning their values in `repo`
+ * as a string and `refspecs` as a null-terminated array of strings. If `repo`
+ * is not provided in argv, it is set to NULL.
+ */
+static void parse_repo_refspecs(int argc, const char **argv, const char **repo,
+		const char ***refspecs)
+{
+	if (argc > 0) {
+		*repo = *argv++;
+		argc--;
+	} else
+		*repo = NULL;
+	*refspecs = argv;
+}
+
+/**
+ * Runs git-fetch, returning its exit status. `repo` and `refspecs` are the
+ * repository and refspecs to fetch, or NULL if they are not provided.
+ */
+static int run_fetch(const char *repo, const char **refspecs)
+{
+	struct argv_array args = ARGV_ARRAY_INIT;
+	int ret;
+
+	argv_array_pushl(&args, "fetch", "--update-head-ok", NULL);
+	if (repo)
+		argv_array_push(&args, repo);
+	while (*refspecs)
+		argv_array_push(&args, *refspecs++);

As you cannot say "git pull refspecs...", the above might be more
clear if you spelled it like this instead:

	if (repo) {
		argv_array_push(&args, repo);
		argv_array_pushv(&args, refspecs);
	} else if (*refspecs) {
        	die("BUG: refspec without repo?");
	}

+/**
+ * Runs git-merge, returning its exit status.
+ */
+static int run_merge(void)
+{
+	int ret;
+	struct argv_array args = ARGV_ARRAY_INIT;
+
+	argv_array_pushl(&args, "merge", NULL);
+	argv_array_push(&args, "FETCH_HEAD");
+	ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
+	argv_array_clear(&args);
+	return ret;
+}

No frills yet, which is a good way to start with and show the
overall structure.