String source = "rule 'q'\nagenda-group 'x'\nwhen\n foo \nthen\n bar 42\nend";
String drl = ex.expand( source );
assertFalse( ex.hasErrors() );
ex = new DefaultExpander();
ex.addDSLMapping( file.getMapping() );
source = "rule 'q' agenda-group 'x'\nwhen\n foos \nthen\n bar 42\n end";
drl = ex.expand( source );
//System.out.println( drl );
assertTrue( ex.hasErrors() );