assertNull(tested.resolveValue("b"));
}
@Test
public void testSimpleSubstitution() {
VariableSource sourceA = variableSource("a=${x}","y=2");
VariableSource sourceB = variableSource("x=1", "b=$y");
VariableResolver tested = new VariableResolver(sourceA, sourceB);
assertEquals("1", tested.resolveValue("x"));
assertEquals("1", tested.resolveValue("a"));
assertEquals("2", tested.resolveValue("b"));