content: /*
   * 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.util.construction;
  
  import static org.hamcrest.MatcherAssert.assertThat;
  
  import java.io.Serializable;
  import java.util.Map;
  import org.apache.beam.sdk.runners.AppliedPTransform;
  import org.apache.beam.sdk.runners.PTransformOverrideFactory.ReplacementOutput;
  import org.apache.beam.sdk.testing.TestPipeline;
  import org.apache.beam.sdk.transforms.Create;
  import org.apache.beam.sdk.transforms.MapElements;
  import org.apache.beam.sdk.transforms.SimpleFunction;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.PCollectionList;
  import org.apache.beam.sdk.values.PValues;
  import org.apache.beam.sdk.values.TaggedPValue;
  import org.hamcrest.Matchers;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.rules.ExpectedException;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  
  /** Tests for {@link SingleInputOutputOverrideFactory}. */
  @RunWith(JUnit4.class)
  public class SingleInputOutputOverrideFactoryTest implements Serializable {
    @Rule public transient ExpectedException thrown = ExpectedException.none();
  
    @Rule
    public transient TestPipeline pipeline =
        TestPipeline.create().enableAbandonedNodeEnforcement(false);
  
    private transient SingleInputOutputOverrideFactory<
            PCollection<? extends Integer>, PCollection<Integer>, MapElements<Integer, Integer>>
        factory =
            new SingleInputOutputOverrideFactory<
                PCollection<? extends Integer>,
                PCollection<Integer>,
                MapElements<Integer, Integer>>() {
              @Override
              public PTransformReplacement<PCollection<? extends Integer>, PCollection<Integer>>
                  getReplacementTransform(
                      AppliedPTransform<
                              PCollection<? extends Integer>,
                              PCollection<Integer>,
                              MapElements<Integer, Integer>>
                          transform) {
                return PTransformReplacement.of(
                    PTransformReplacements.getSingletonMainInput(transform),
                    transform.getTransform());
              }
            };
  
    private SimpleFunction<Integer, Integer> fn =
        new SimpleFunction<Integer, Integer>() {
          @Override
          public Integer apply(Integer input) {
            return input - 1;
          }
        };
  
    @Test
    public void testMapOutputs() {
      PCollection<Integer> input = pipeline.apply(Create.of(1, 2, 3));
      PCollection<Integer> output = input.apply("Map", MapElements.via(fn));
      PCollection<Integer> reappliedOutput = input.apply("ReMap", MapElements.via(fn));
      Map<PCollection<?>, ReplacementOutput> replacementMap =
          factory.mapOutputs(PValues.expandOutput(output), reappliedOutput);
      assertThat(
          replacementMap,
          Matchers.hasEntry(
              reappliedOutput,
              ReplacementOutput.of(
                  TaggedPValue.ofExpandedValue(output),
                  TaggedPValue.ofExpandedValue(reappliedOutput))));
    }
  
    @Test
    public void testMapOutputsMultipleOriginalOutputsFails() {
      PCollection<Integer> input = pipeline.apply(Create.of(1, 2, 3));
      PCollection<Integer> output = input.apply("Map", MapElements.via(fn));
      PCollection<Integer> reappliedOutput = input.apply("ReMap", MapElements.via(fn));
      thrown.expect(IllegalArgumentException.class);
      factory.mapOutputs(
          PValues.expandOutput(PCollectionList.of(output).and(input).and(reappliedOutput)),
          reappliedOutput);
    }
  }
  