public static String substVars(String val, PropertyContainer pc1) throws ScanException {
        return substVars(val, pc1, null);
    }
@Test
    public void nonCircularGraphShouldWork() throws ScanException {
        context.putProperty("A", "${B} and ${C}");
        context.putProperty("B", "${B1}");
        context.putProperty("B1", "B1-value");
        context.putProperty("C", "${C1} and ${B}");
        context.putProperty("C1", "C1-value");

        String result = OptionHelper.substVars("${A}", context);
        assertEquals("B1-value and C1-value and B1-value", result);
    }