gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/strategy/optimization/OrderLimitStrategyTest.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
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package org.apache.tinkerpop.gremlin.process.traversal.strategy.optimization;

import org.apache.tinkerpop.gremlin.process.computer.traversal.step.map.TraversalVertexProgramStep;
import org.apache.tinkerpop.gremlin.process.traversal.Traversal;
import org.apache.tinkerpop.gremlin.process.traversal.TraversalStrategies;
import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.__;
import org.apache.tinkerpop.gremlin.process.traversal.step.map.OrderGlobalStep;
import org.apache.tinkerpop.gremlin.process.traversal.util.DefaultTraversalStrategies;
import org.apache.tinkerpop.gremlin.process.traversal.util.EmptyTraversal;
import org.apache.tinkerpop.gremlin.process.traversal.util.TraversalHelper;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;

import java.util.Arrays;

import static org.junit.Assert.assertEquals;

/**
 * @author Marko A. Rodriguez (http://markorodriguez.com)
 */
@RunWith(Parameterized.class)
public class OrderLimitStrategyTest {

    @Parameterized.Parameter(value = 0)
    public Traversal traversal;

    @Parameterized.Parameter(value = 1)
    public long limit;

    void applyOrderLimitStrategyStrategy(final Traversal traversal) {
        final TraversalStrategies strategies = new DefaultTraversalStrategies();
        strategies.addStrategies(OrderLimitStrategy.instance());
        traversal.asAdmin().setStrategies(strategies);
        traversal.asAdmin().applyStrategies();
    }

    @Test
    public void doTest() {
        traversal.asAdmin().setParent(new TraversalVertexProgramStep(EmptyTraversal.instance(), EmptyTraversal.instance())); // trick it
        applyOrderLimitStrategyStrategy(traversal);
        assertEquals(limit, TraversalHelper.getFirstStepOfAssignableClass(OrderGlobalStep.class, traversal.asAdmin()).get().getLimit());
    }

    @Parameterized.Parameters(name = "{0}")
    public static Iterable<Object> generateTestParameters() {
        return Arrays.asList(new Object[][]{
                {__.order().limit(1), 1l},
                {__.out().order().range(7, 15), 15l},
                {__.order().select("a").limit(7), 7l},
                {__.order().out().limit(10), Long.MAX_VALUE}});
    }
}