Merge branch 'ds/commit-graph-octopus-fix'

commit-graph did not handle commits with more than two parents
correctly, which has been corrected.

* ds/commit-graph-octopus-fix:
  commit-graph: fix bug around octopus merges

Author: gitster

commit-graph.c

@@ -1636,7 +1636,7 @@ static void sort_and_scan_merged_commits(struct write_commit_graph_context *ctx)
 				num_parents++;
 
 			if (num_parents > 2)
-				ctx->num_extra_edges += num_parents - 2;
+				ctx->num_extra_edges += num_parents - 1;
 		}
 	}
 

t/t5324-split-commit-graph.sh

@@ -319,7 +319,9 @@ test_expect_success 'add octopus merge' '
 	git merge commits/3 commits/4 &&
 	git branch merge/octopus &&
 	git commit-graph write --reachable --split &&
-	git commit-graph verify &&
+	git commit-graph verify 2>err &&
+	test_line_count = 3 err &&
+	test_i18ngrep ! warning err &&
 	test_line_count = 3 $graphdir/commit-graph-chain
 '