/*
 * 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.beam.sdk.transforms;

import static org.hamcrest.Matchers.empty;
import static org.junit.Assert.assertThat;

import org.apache.beam.sdk.transforms.display.DisplayData;
import org.apache.beam.sdk.values.PCollection;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/**
 * Tests for {@link PTransform} base class.
 */
@RunWith(JUnit4.class)
public class PTransformTest {
  @Test
  public void testPopulateDisplayDataDefaultBehavior() {
    PTransform<PCollection<String>, PCollection<String>> transform =
        new PTransform<PCollection<String>, PCollection<String>>() {
          @Override
          public PCollection<String> expand(PCollection<String> begin) {
            throw new IllegalArgumentException("Should never be applied");
          }
        };
    DisplayData displayData = DisplayData.from(transform);
    assertThat(displayData.items(), empty());
  }
}