private void assertOverride(String input, Environment environment, RegionName region, CloudName cloudName, String expected) {
        var inputDoc = Xml.getDocument(new StringReader(input));
        try {
            var newDoc = new OverrideProcessor(InstanceName.from("default"), environment, region, cloudName, Tags.empty())
                    .process(inputDoc);
            TestBase.assertDocument(expected, newDoc);
        } catch (TransformerException e) {
            throw new RuntimeException(e);
        }
    }
Tests that searchers referred to with idref are overridden per cloud
and that searchers not referred to with idref are not overridden.
config-application-package/src/test/java/com/yahoo/config/application/OverrideProcessorTest.java