commit 9b88e78ce7dfa88adba6acc7e68ae6fa557d48d1
from: Stefan Sperling <stsp@stsp.name>
date: Sun Nov 18 22:08:01 2018 UTC

don't add duplicates to commit graph's open branches set

commit - d2c2d78192e0bcd012717d912831c878081bf2f8
commit + 9b88e78ce7dfa88adba6acc7e68ae6fa557d48d1
blob - be53a1239bba3e566f78483c4445ede4cf3ec773
blob + 5e0f78693f0011f1b6262c49bfa355856ece0bea
--- lib/commit_graph.c
+++ lib/commit_graph.c
@@ -283,10 +283,11 @@ advance_branch(struct got_commit_graph *graph,
 
 	if (graph->flags & GOT_COMMIT_GRAPH_FIRST_PARENT_TRAVERSAL) {
 		qid = SIMPLEQ_FIRST(&commit->parent_ids);
-		if (qid == NULL)
+		if (qid == NULL ||
+		    got_object_idset_get(graph->open_branches, qid->id))
 			return NULL;
-		err = got_object_idset_add(graph->open_branches, qid->id, node);
-		return err;
+		return got_object_idset_add(graph->open_branches,
+		    qid->id, node);
 	}
 
 	/*
@@ -307,6 +308,8 @@ advance_branch(struct got_commit_graph *graph,
 
 			if (got_object_idset_get(graph->node_ids, qid->id))
 				continue; /* parent already traversed */
+			if (got_object_idset_get(graph->open_branches, qid->id))
+				continue;
 
 			err = got_object_id_by_path(&id, repo, qid->id,
 			    graph->path);