*/
int graph_is_commit_finished(struct git_graph const *graph);
+/*
+ * Output the next line for a graph.
+ * This formats the next graph line into the specified strbuf. It is not
+ * terminated with a newline.
+ *
+ * Returns 1 if the line includes the current commit, and 0 otherwise.
+ * graph_next_line() will return 1 exactly once for each time
+ * graph_update() is called.
+ */
+int graph_next_line(struct git_graph *graph, struct strbuf *sb);
+
/*
* graph_show_*: helper functions for printing to stdout