package org.neo4j.kernel.impl.traversal;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNotNull;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
import org.junit.BeforeClass;
import org.junit.Test;
import org.neo4j.graphdb.Path;
import org.neo4j.graphdb.traversal.TraversalDescription;
import org.neo4j.graphdb.traversal.Traverser;
import org.neo4j.helpers.Predicate;
import org.neo4j.kernel.Traversal;
import org.neo4j.kernel.Uniqueness;
public class DepthPitfallGraphTest extends AbstractTestBase
{
/* Layout:
* _(2)--__
* / \
* (1)-(3)-_ (6)
* |\_ \ /
* | (4)__ \/
* \_______(5)
*/
private static final String[] THE_WORLD_AS_WE_KNOW_IT = new String[] {
"1 TO 2", "1 TO 3", "1 TO 4", "5 TO 3", "1 TO 5", "4 TO 5",
"2 TO 6", "5 TO 6" };
private static final String[] NODE_UNIQUE_PATHS = new String[] { "1",
"1,2", "1,2,6", "1,2,6,5", "1,2,6,5,3", "1,2,6,5,4", "1,3",
"1,3,5", "1,3,5,4", "1,3,5,6", "1,3,5,6,2", "1,4", "1,4,5",
"1,4,5,3", "1,4,5,6", "1,4,5,6,2", "1,5", "1,5,3", "1,5,4",
"1,5,6", "1,5,6,2" };
private static final String[] RELATIONSHIP_UNIQUE_EXTRA_PATHS = new String[] {
"1,2,6,5,1", "1,2,6,5,1,3", "1,2,6,5,1,3,5", "1,2,6,5,1,3,5,4",
"1,2,6,5,1,3,5,4,1", "1,2,6,5,1,4", "1,2,6,5,1,4,5",
"1,2,6,5,1,4,5,3", "1,2,6,5,1,4,5,3,1", "1,2,6,5,3,1",
"1,2,6,5,3,1,4", "1,2,6,5,3,1,4,5", "1,2,6,5,3,1,4,5,1",
"1,2,6,5,3,1,5", "1,2,6,5,3,1,5,4", "1,2,6,5,3,1,5,4,1",
"1,2,6,5,4,1", "1,2,6,5,4,1,3", "1,2,6,5,4,1,3,5",
"1,2,6,5,4,1,3,5,1", "1,2,6,5,4,1,5", "1,2,6,5,4,1,5,3",
"1,2,6,5,4,1,5,3,1", "1,3,5,1", "1,3,5,1,2", "1,3,5,1,2,6",
"1,3,5,1,2,6,5", "1,3,5,1,2,6,5,4", "1,3,5,1,2,6,5,4,1",
"1,3,5,1,4", "1,3,5,1,4,5", "1,3,5,1,4,5,6", "1,3,5,1,4,5,6,2",
"1,3,5,1,4,5,6,2,1", "1,3,5,4,1", "1,3,5,4,1,2", "1,3,5,4,1,2,6",
"1,3,5,4,1,2,6,5", "1,3,5,4,1,2,6,5,1", "1,3,5,4,1,5",
"1,3,5,4,1,5,6", "1,3,5,4,1,5,6,2", "1,3,5,4,1,5,6,2,1",
"1,3,5,6,2,1", "1,3,5,6,2,1,4", "1,3,5,6,2,1,4,5",
"1,3,5,6,2,1,4,5,1", "1,3,5,6,2,1,5", "1,3,5,6,2,1,5,4",
"1,3,5,6,2,1,5,4,1", "1,4,5,1", "1,4,5,1,2", "1,4,5,1,2,6",
"1,4,5,1,2,6,5", "1,4,5,1,2,6,5,3", "1,4,5,1,2,6,5,3,1",
"1,4,5,1,3", "1,4,5,1,3,5", "1,4,5,1,3,5,6", "1,4,5,1,3,5,6,2",
"1,4,5,1,3,5,6,2,1", "1,4,5,3,1", "1,4,5,3,1,2", "1,4,5,3,1,2,6",
"1,4,5,3,1,2,6,5", "1,4,5,3,1,2,6,5,1", "1,4,5,3,1,5",
"1,4,5,3,1,5,6", "1,4,5,3,1,5,6,2", "1,4,5,3,1,5,6,2,1",
"1,4,5,6,2,1", "1,4,5,6,2,1,3", "1,4,5,6,2,1,3,5",
"1,4,5,6,2,1,3,5,1", "1,4,5,6,2,1,5", "1,4,5,6,2,1,5,3",
"1,4,5,6,2,1,5,3,1", "1,5,3,1", "1,5,3,1,2", "1,5,3,1,2,6",
"1,5,3,1,2,6,5", "1,5,3,1,2,6,5,4", "1,5,3,1,2,6,5,4,1",
"1,5,3,1,4", "1,5,3,1,4,5", "1,5,3,1,4,5,6", "1,5,3,1,4,5,6,2",
"1,5,3,1,4,5,6,2,1", "1,5,4,1", "1,5,4,1,2", "1,5,4,1,2,6",
"1,5,4,1,2,6,5", "1,5,4,1,2,6,5,3", "1,5,4,1,2,6,5,3,1",
"1,5,4,1,3", "1,5,4,1,3,5", "1,5,4,1,3,5,6", "1,5,4,1,3,5,6,2",
"1,5,4,1,3,5,6,2,1", "1,5,6,2,1", "1,5,6,2,1,3", "1,5,6,2,1,3,5",
"1,5,6,2,1,3,5,4", "1,5,6,2,1,3,5,4,1", "1,5,6,2,1,4",
"1,5,6,2,1,4,5", "1,5,6,2,1,4,5,3", "1,5,6,2,1,4,5,3,1" };
@BeforeClass
public static void setup()
{
createGraph( THE_WORLD_AS_WE_KNOW_IT );
}
@Test
public void testSmallestPossibleInit() throws Exception
{
Traverser traversal = Traversal.description().traverse( referenceNode() );
int count = 0;
for ( Path position : traversal )
{
count++;
assertNotNull( position );
assertNotNull( position.endNode() );
if ( position.length() > 0 )
{
assertNotNull( position.lastRelationship() );
}
assertNotNull( position.length() );
}
assertFalse( "empty traversal", count == 0 );
}
@Test
public void testAllNodesAreReturnedOnceDepthFirst() throws Exception
{
testAllNodesAreReturnedOnce( Traversal.description().depthFirst() );
}
@Test
public void testAllNodesAreReturnedOnceBreadthFirst() throws Exception
{
testAllNodesAreReturnedOnce( Traversal.description().breadthFirst() );
}
private void testAllNodesAreReturnedOnce( TraversalDescription traversal )
{
Traverser traverser = traversal.uniqueness( Uniqueness.NODE_GLOBAL ).traverse(
referenceNode() );
expectNodes( traverser, "1", "2", "3", "4", "5", "6" );
}
@Test
public void testNodesAreReturnedOnceWhenSufficientRecentlyUniqueDepthFirst()
throws Exception
{
testNodesAreReturnedOnceWhenSufficientRecentlyUnique(
Traversal.description().depthFirst() );
}
@Test
public void testNodesAreReturnedOnceWhenSufficientRecentlyUniqueBreadthFirst()
throws Exception
{
testNodesAreReturnedOnceWhenSufficientRecentlyUnique(
Traversal.description().breadthFirst() );
}
private void testNodesAreReturnedOnceWhenSufficientRecentlyUnique(
TraversalDescription description )
{
Traverser traverser = description.uniqueness( Uniqueness.NODE_RECENT, 6 ).traverse(
referenceNode() );
expectNodes( traverser, "1", "2", "3", "4", "5", "6" );
}
@Test
public void testAllRelationshipsAreReturnedOnceDepthFirst()
throws Exception
{
testAllRelationshipsAreReturnedOnce( Traversal.description().depthFirst() );
}
@Test
public void testAllRelationshipsAreReturnedOnceBreadthFirst()
throws Exception
{
testAllRelationshipsAreReturnedOnce( Traversal.description().breadthFirst() );
}
private void testAllRelationshipsAreReturnedOnce(
TraversalDescription description ) throws Exception
{
Traverser traverser = Traversal.description().uniqueness(
Uniqueness.RELATIONSHIP_GLOBAL ).traverse( referenceNode() );
expectRelationships( traverser, THE_WORLD_AS_WE_KNOW_IT );
}
@Test
public void testRelationshipsAreReturnedOnceWhenSufficientRecentlyUniqueDepthFirst()
throws Exception
{
testRelationshipsAreReturnedOnceWhenSufficientRecentlyUnique(
Traversal.description().depthFirst() );
}
@Test
public void testRelationshipsAreReturnedOnceWhenSufficientRecentlyUniqueBreadthFirst()
throws Exception
{
testRelationshipsAreReturnedOnceWhenSufficientRecentlyUnique(
Traversal.description().breadthFirst() );
}
private void testRelationshipsAreReturnedOnceWhenSufficientRecentlyUnique(
TraversalDescription description ) throws Exception
{
Traverser traverser = description.uniqueness(
Uniqueness.RELATIONSHIP_RECENT, THE_WORLD_AS_WE_KNOW_IT.length ).traverse(
referenceNode() );
expectRelationships( traverser, THE_WORLD_AS_WE_KNOW_IT );
}
@Test
public void testAllUniqueNodePathsAreReturnedDepthFirst() throws Exception
{
testAllUniqueNodePathsAreReturned( Traversal.description().depthFirst() );
}
@Test
public void testAllUniqueNodePathsAreReturnedBreadthFirst() throws Exception
{
testAllUniqueNodePathsAreReturned( Traversal.description().breadthFirst() );
}
private void testAllUniqueNodePathsAreReturned( TraversalDescription description )
throws Exception
{
Traverser traverser = description.uniqueness(
Uniqueness.NODE_PATH ).traverse( referenceNode() );
expectPaths( traverser, NODE_UNIQUE_PATHS );
}
@Test
public void testAllUniqueRelationshipPathsAreReturnedDepthFirst() throws Exception
{
testAllUniqueRelationshipPathsAreReturned( Traversal.description().depthFirst() );
}
@Test
public void testAllUniqueRelationshipPathsAreReturnedBreadthFirst() throws Exception
{
testAllUniqueRelationshipPathsAreReturned( Traversal.description().breadthFirst() );
}
private void testAllUniqueRelationshipPathsAreReturned( TraversalDescription description )
throws Exception
{
Set<String> expected = new HashSet<String>(
Arrays.asList( NODE_UNIQUE_PATHS ) );
expected.addAll( Arrays.asList( RELATIONSHIP_UNIQUE_EXTRA_PATHS ) );
Traverser traverser = description.uniqueness(
Uniqueness.RELATIONSHIP_PATH ).traverse( referenceNode() );
expectPaths( traverser, expected );
}
@Test
public void canPruneTraversalAtSpecificDepthDepthFirst()
{
canPruneTraversalAtSpecificDepth( Traversal.description().depthFirst() );
}
@Test
public void canPruneTraversalAtSpecificDepthBreadthFirst()
{
canPruneTraversalAtSpecificDepth( Traversal.description().breadthFirst() );
}
private void canPruneTraversalAtSpecificDepth( TraversalDescription description )
{
Traverser traverser = description.uniqueness(
Uniqueness.NONE ).prune( Traversal.pruneAfterDepth( 1 ) ).traverse(
referenceNode() );
expectNodes( traverser, "1", "2", "3", "4", "5" );
}
@Test
public void canPreFilterNodesDepthFirst()
{
canPreFilterNodes( Traversal.description().depthFirst() );
}
@Test
public void canPreFilterNodesBreadthFirst()
{
canPreFilterNodes( Traversal.description().breadthFirst() );
}
private void canPreFilterNodes( TraversalDescription description )
{
Traverser traverser = description.uniqueness(
Uniqueness.NONE ).prune( Traversal.pruneAfterDepth( 2 ) ).filter(
new Predicate<Path>()
{
public boolean accept( Path position )
{
return position.length() == 2;
}
} ).traverse( referenceNode() );
expectPaths( traverser, "1,2,6", "1,3,5", "1,4,5", "1,5,3", "1,5,4",
"1,5,6" );
}
}