KieBuilder kieBuilder = ks.newKieBuilder( kfs ).buildAll();
assertEquals( 0, kieBuilder.getResults().getMessages( org.kie.api.builder.Message.Level.ERROR ).size() );
kfs.write( "src/main/resources/r2_1.drl", drl2 );
IncrementalResults addResults = ( (InternalKieBuilder) kieBuilder ).createFileSet( "src/main/resources/r2_1.drl" ).build();
assertEquals( 0, addResults.getAddedMessages().size() );
assertEquals( 0, addResults.getRemovedMessages().size() );
kfs.write( "src/main/resources/r2_2.drl", drl2 );
IncrementalResults removeResults = ( (InternalKieBuilder) kieBuilder ).createFileSet( "src/main/resources/r2_2.drl" ).build();
assertEquals( 1, removeResults.getAddedMessages().size() );
assertEquals( 0, removeResults.getRemovedMessages().size() );
}