content: package aima.test.core.unit.search.uninformed;
  
  import aima.core.environment.nqueens.NQueensBoard;
  import aima.core.environment.nqueens.NQueensFunctions;
  import aima.core.environment.nqueens.QueenAction;
  import aima.core.search.framework.Node;
  import aima.core.search.framework.SearchForActions;
  import aima.core.search.framework.problem.GeneralProblem;
  import aima.core.search.framework.problem.Problem;
  import aima.core.search.uninformed.DepthLimitedSearch;
  import org.junit.Assert;
  import org.junit.Test;
  
  import java.util.List;
  import java.util.Optional;
  
  /**
   * Tests depth-limited search.
   * @author Ruediger Lunde
   */
  public class DepthLimitedSearchTest {
  
  	@Test
  	public void testSuccessfulDepthLimitedSearch() throws Exception {
  		Problem<NQueensBoard, QueenAction> problem = new GeneralProblem<>(new NQueensBoard(8),
  				NQueensFunctions::getIFActions, NQueensFunctions::getResult, NQueensFunctions::testGoal);
  		SearchForActions<NQueensBoard, QueenAction> search = new DepthLimitedSearch<>(8);
  		Optional<List<QueenAction>> actions = search.findActions(problem);
  		Assert.assertTrue(actions.isPresent());
  		assertCorrectPlacement(actions.get());
  		Assert.assertEquals("113", search.getMetrics().get("nodesExpanded"));
  	}
  
  	@Test
  	public void testCutOff() throws Exception {
  		Problem<NQueensBoard, QueenAction> problem = new GeneralProblem<>(new NQueensBoard(8),
  				NQueensFunctions::getIFActions, NQueensFunctions::getResult, NQueensFunctions::testGoal);
  		DepthLimitedSearch<NQueensBoard, QueenAction> search = new DepthLimitedSearch<>(1);
  		Optional<Node<NQueensBoard, QueenAction>> result = search.findNode(problem);
  		Assert.assertEquals(true, search.isCutoffResult(result));
  	}
  
  	@Test
  	public void testFailure() throws Exception {
  		Problem<NQueensBoard, QueenAction> problem = new GeneralProblem<>(new NQueensBoard(3),
  				NQueensFunctions::getIFActions, NQueensFunctions::getResult, NQueensFunctions::testGoal);
  		DepthLimitedSearch<NQueensBoard, QueenAction> search = new DepthLimitedSearch<>(5);
  		Optional<List<QueenAction>> actions = search.findActions(problem);
  		Assert.assertFalse(actions.isPresent()); // failure
  	}
  
  	//
  	// PRIVATE METHODS
  	//
  	private void assertCorrectPlacement(List<QueenAction> actions) {
  		Assert.assertEquals(8, actions.size());
  		Assert.assertEquals("Action[name=placeQueenAt, location=(0, 0)]", actions.get(0).toString());
  		Assert.assertEquals("Action[name=placeQueenAt, location=(1, 4)]", actions.get(1).toString());
  		Assert.assertEquals("Action[name=placeQueenAt, location=(2, 7)]", actions.get(2).toString());
  		Assert.assertEquals("Action[name=placeQueenAt, location=(3, 5)]", actions.get(3).toString());
  		Assert.assertEquals("Action[name=placeQueenAt, location=(4, 2)]", actions.get(4).toString());
  		Assert.assertEquals("Action[name=placeQueenAt, location=(5, 6)]", actions.get(5).toString());
  		Assert.assertEquals("Action[name=placeQueenAt, location=(6, 1)]", actions.get(6).toString());
  		Assert.assertEquals("Action[name=placeQueenAt, location=(7, 3)]", actions.get(7).toString());
  	}
  }