/*
 * 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.
 */
package org.apache.tinkerpop.gremlin.language.grammar;

import org.antlr.v4.runtime.CharStreams;
import org.antlr.v4.runtime.CommonTokenStream;
import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource;
import org.apache.tinkerpop.gremlin.structure.util.empty.EmptyGraph;
import org.junit.Before;
import org.junit.Test;

import java.util.HashMap;

import static org.apache.tinkerpop.gremlin.process.traversal.AnonymousTraversalSource.traversal;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.fail;

/**
 * Can only test against {@link EmptyGraph} which won't support transactions so all it can verify is that {@code tx()}
 * is called to fail.
 */
public class TraversalSourceTxVisitorTest {

    private GraphTraversalSource g;
    private GremlinAntlrToJava antlrToLanguage;

    @Before
    public void setup()  {
        g = traversal().withEmbedded(EmptyGraph.instance());
        antlrToLanguage = new GremlinAntlrToJava(g);
    }

    @Test
    public void shouldHandleTxCommit() {
        try {
            eval("g.tx().commit()");
            fail("Should not have succeeded because EmptyGraph does not support transactions.");
        } catch(UnsupportedOperationException uoe) {
            assertEquals("Graph does not support transactions", uoe.getMessage());
        }
    }

    private Object eval(final String query) {
        final GremlinLexer lexer = new GremlinLexer(CharStreams.fromString(query));
        final GremlinParser parser = new GremlinParser(new CommonTokenStream(lexer));
        return antlrToLanguage.visit(parser.queryList());
    }
}
