Graph graph2 = new Graph();
        addEdge(graph2, "a", "b");
        addEdge(graph2, "b", "c");
        CycleDetectedException cde = assertThrows(CycleDetectedException.class, () -> addEdge(graph2, "c", "a"));
        List<String> cycle = cde.getCycle();
        assertNotNull(cycle, "Cycle should be not null");
        assertTrue(cycle.contains("a"), "Cycle contains 'a'");

		tests: []testFnc{
			testWrite{"ab", 2, nil},
			testRemaining{6, 3},
			testReadFrom{fileOps{int64(3), "cde"}, 6, nil},
			testRemaining{0, 0},
		},
	}, {
		maker: makeSparse{makeReg{5, "abcde"}, sparseHoles{{2, 3}}, 8},
		tests: []testFnc{
			testReadFrom{fileOps{"ab", int64(3), "cde"}, 8, nil},
			testRemaining{0, 0},
		},
	}, {
		maker: makeSparse{makeReg{5, "abcde"}, sparseHoles{{2, 3}}, 8},

                    final CycleDetectedException cde = (CycleDetectedException) cycle.getException();
                    throw new ProjectBuildingException(
                            null,
                            "The projects in the reactor contain a cyclic reference: " + cycle.getMessage(),
                            null,
                            cde);
                }

			testRemaining{0, 0},
		},
	}, {
		maker: makeSparse{makeReg{"abcde", 5}, sparseDatas{{0, 2}, {5, 3}}, 8},
		tests: []testFnc{
			testRemaining{8, 5},
			testWriteTo{fileOps{"ab", int64(3), "cde"}, 8, nil},
			testRemaining{0, 0},
		},
	}, {
		maker: makeSparse{makeReg{"abcde", 5}, sparseDatas{{0, 2}, {5, 3}}, 10},
		tests: []testFnc{
			testRemaining{10, 5},