@Test
    void package_is_null_when_not_explicitly_given() {
        String namespace = "test.namespace";
        DefParser parser = createParser("namespace=" + namespace + "\n");
        CNode root = parser.getTree();
        assertNull(root.getPackage());
    }
Tests setting explicit java package in the def file.

@author gjoranv
configgen/src/test/java/com/yahoo/config/codegen/DefParserPackageTest.java