test-diamond
-{ } [ test-branch-splitting ] unit-test
+[ ] [ test-branch-splitting ] unit-test
V{ T{ ##branch } } 0 test-bb
2 { 3 4 } edges
-{ } [ test-branch-splitting ] unit-test
+[ ] [ test-branch-splitting ] unit-test
V{ T{ ##branch } } 0 test-bb
2 4 edge
-{ } [ test-branch-splitting ] unit-test
+[ ] [ test-branch-splitting ] unit-test
V{ T{ ##branch } } 0 test-bb
1 2 edge
-{ } [ test-branch-splitting ] unit-test
+[ ] [ test-branch-splitting ] unit-test