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 static org.hamcrest.Matchers.equalTo;
  
  import java.util.Collections;
  import org.apache.beam.sdk.io.GenerateSequence;
  import org.apache.beam.sdk.runners.AppliedPTransform;
  import org.apache.beam.sdk.testing.TestPipeline;
  import org.apache.beam.sdk.transforms.Create;
  import org.apache.beam.sdk.transforms.DoFn;
  import org.apache.beam.sdk.transforms.ParDo;
  import org.apache.beam.sdk.transforms.View;
  import org.apache.beam.sdk.transforms.resourcehints.ResourceHints;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.PCollectionView;
  import org.apache.beam.sdk.values.PValues;
  import org.apache.beam.sdk.values.TupleTag;
  import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.collect.ImmutableMap;
  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 PTransformReplacements}. */
  @RunWith(JUnit4.class)
  public class PTransformReplacementsTest {
    @Rule public TestPipeline pipeline = TestPipeline.create().enableAbandonedNodeEnforcement(false);
    @Rule public ExpectedException thrown = ExpectedException.none();
    private PCollection<Long> mainInput = pipeline.apply(GenerateSequence.from(0));
    private PCollectionView<String> sideInput =
        pipeline.apply(Create.of("foo")).apply(View.asSingleton());
  
    private PCollection<Long> output = mainInput.apply(ParDo.of(new TestDoFn()));
  
    @Test
    public void getMainInputSingleOutputSingleInput() {
      AppliedPTransform<PCollection<Long>, ?, ?> application =
          AppliedPTransform.of(
              "application",
              Collections.singletonMap(new TupleTag<Long>(), mainInput),
              Collections.singletonMap(new TupleTag<Long>(), output),
              ParDo.of(new TestDoFn()),
              ResourceHints.create(),
              pipeline);
      PCollection<Long> input = PTransformReplacements.getSingletonMainInput(application);
      assertThat(input, equalTo(mainInput));
    }
  
    @Test
    public void getMainInputSingleOutputSideInputs() {
      AppliedPTransform<PCollection<Long>, ?, ?> application =
          AppliedPTransform.of(
              "application",
              ImmutableMap.<TupleTag<?>, PCollection<?>>builder()
                  .put(new TupleTag<Long>(), mainInput)
                  .put(sideInput.getTagInternal(), sideInput.getPCollection())
                  .build(),
              Collections.singletonMap(new TupleTag<Long>(), output),
              ParDo.of(new TestDoFn()).withSideInputs(sideInput),
              ResourceHints.create(),
              pipeline);
      PCollection<Long> input = PTransformReplacements.getSingletonMainInput(application);
      assertThat(input, equalTo(mainInput));
    }
  
    @Test
    public void getMainInputExtraMainInputsThrows() {
      PCollection<Long> notInParDo = pipeline.apply("otherPCollection", Create.of(1L, 2L, 3L));
      ImmutableMap<TupleTag<?>, PCollection<?>> inputs =
          ImmutableMap.<TupleTag<?>, PCollection<?>>builder()
              .putAll(PValues.expandInput(mainInput))
              // Not represnted as an input
              .put(new TupleTag<Long>(), notInParDo)
              .put(sideInput.getTagInternal(), sideInput.getPCollection())
              .build();
      AppliedPTransform<PCollection<Long>, ?, ?> application =
          AppliedPTransform.of(
              "application",
              inputs,
              Collections.singletonMap(new TupleTag<Long>(), output),
              ParDo.of(new TestDoFn()).withSideInputs(sideInput),
              ResourceHints.create(),
              pipeline);
      thrown.expect(IllegalArgumentException.class);
      thrown.expectMessage("multiple inputs");
      thrown.expectMessage("not additional inputs");
      thrown.expectMessage(mainInput.toString());
      thrown.expectMessage(notInParDo.toString());
      PTransformReplacements.getSingletonMainInput(application);
    }
  
    @Test
    public void getMainInputNoMainInputsThrows() {
      ImmutableMap<TupleTag<?>, PCollection<?>> inputs =
          ImmutableMap.<TupleTag<?>, PCollection<?>>builder()
              .put(sideInput.getTagInternal(), sideInput.getPCollection())
              .build();
      AppliedPTransform<PCollection<Long>, ?, ?> application =
          AppliedPTransform.of(
              "application",
              inputs,
              Collections.singletonMap(new TupleTag<Long>(), output),
              ParDo.of(new TestDoFn()).withSideInputs(sideInput),
              ResourceHints.create(),
              pipeline);
      thrown.expect(IllegalArgumentException.class);
      thrown.expectMessage("No main input");
      PTransformReplacements.getSingletonMainInput(application);
    }
  
    private static class TestDoFn extends DoFn<Long, Long> {
      @ProcessElement
      public void process(ProcessContext context) {}
    }
  }
  