settings.addMirror( mirror );
mirror = new Mirror();
mirror.setId( "illegal\\:/chars" );
mirror.setUrl( "http://void" );
mirror.setMirrorOf( "void" );
settings.addMirror( mirror );
SimpleProblemCollector problems = new SimpleProblemCollector();
validator.validate( settings, problems );
assertEquals( 4, problems.messages.size() );
assertContains( problems.messages.get( 0 ), "'mirrors.mirror.id' must not be 'local'" );