@Test(expected = IllegalArgumentException.class)
public void testConfigurationHandling_mergeNewStyle_singleMasterWithMultipleIdlessMergers() throws Exception {

    Dummy.schema = "{\"type\": \"object\", \"properties\": {\"a\": {\"type\": \"integer\"}," +
            " \"b\": {\"type\": \"array\", \"items\": {\"type\": \"string\"}}}}";
    Dummy.extensionId = "ext";
    ModelNode cfg1 = ModelNode.fromJSONString("[{\"extension\": \"ext\", \"configuration\": {\"a\": 1, \"b\": [\"x\"]}}]");
    ModelNode cfg2 = ModelNode.fromJSONString("[{\"extension\": \"ext\", \"configuration\": {\"b\": [\"y\"]}}," +
            "{\"extension\": \"ext\", \"configuration\": {\"b\": [\"z\"]}}]");
    Revapi revapi = Revapi.builder().withAnalyzers(Dummy.class).withReporters(TestReporter.class).build();
    AnalysisContext.builder(revapi)
            .withConfiguration(cfg1)
            .mergeConfiguration(cfg2)
            .build();
}