test/jdk/java/util/stream/test/org/openjdk/tests/java/util/stream/WhileOpTest.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */
 package org.openjdk.tests.java.util.stream;

 import org.testng.annotations.Test;

 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.stream.DefaultMethodStreams;
 import java.util.stream.DoubleStream;
 import java.util.stream.IntStream;
 import java.util.stream.LambdaTestHelpers;
 import java.util.stream.LongStream;
 import java.util.stream.OpTestCase;
 import java.util.stream.Stream;
 import java.util.stream.StreamTestDataProvider;
 import java.util.stream.TestData;

 /*
  * @test
  * @bug 8071597 8193856
  * @run main/timeout=240
  */
 @Test
 public class WhileOpTest extends OpTestCase {

     @Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class,
           groups = { "serialization-hostile" })
     public void testTakeWhileOps(String name, TestData.OfRef<Integer> data) {
         for (int size : sizes(data.size())) {
             setContext("takeWhile", size);

             testWhileMulti(data,
                            whileResultAsserter(data, WhileOp.Take, e -> e < size),
                            s -> s.takeWhile(e -> e < size),
                            s -> s.takeWhile(e -> e < size),
                            s -> s.takeWhile(e -> e < size),
                            s -> s.takeWhile(e -> e < size));


             testWhileMulti(data,
                            whileResultAsserter(data, WhileOp.Take, e -> e < size / 2),
                            s -> s.takeWhile(e -> e < size).takeWhile(e -> e < size / 2),
                            s -> s.takeWhile(e -> e < size).takeWhile(e -> e < size / 2),
                            s -> s.takeWhile(e -> e < size).takeWhile(e -> e < size / 2),
                            s -> s.takeWhile(e -> e < size).takeWhile(e -> e < size / 2));
         }
     }

     @Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class,
           groups = { "serialization-hostile" })
     public void testDropWhileOps(String name, TestData.OfRef<Integer> data) {
         for (int size : sizes(data.size())) {
             setContext("dropWhile", size);

             testWhileMulti(data,
                            whileResultAsserter(data, WhileOp.Drop, e -> e < size),
                            s -> s.dropWhile(e -> e < size),
                            s -> s.dropWhile(e -> e < size),
                            s -> s.dropWhile(e -> e < size),
                            s -> s.dropWhile(e -> e < size));

             testWhileMulti(data,
                            whileResultAsserter(data, WhileOp.Drop, e -> e < size),
                            s -> s.dropWhile(e -> e < size / 2).dropWhile(e -> e < size),
                            s -> s.dropWhile(e -> e < size / 2).dropWhile(e -> e < size),
                            s -> s.dropWhile(e -> e < size / 2).dropWhile(e -> e < size),
                            s -> s.dropWhile(e -> e < size / 2).dropWhile(e -> e < size));
         }
     }

     @Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class,
           groups = { "serialization-hostile" })
     public void testDropTakeWhileOps(String name, TestData.OfRef<Integer> data) {
         for (int size : sizes(data.size())) {
             setContext("dropWhile", size);

             testWhileMulti(data,
                            whileResultAsserter(data, WhileOp.Undefined, null),
                            s -> s.dropWhile(e -> e < size / 2).takeWhile(e -> e < size),
                            s -> s.dropWhile(e -> e < size / 2).takeWhile(e -> e < size),
                            s -> s.dropWhile(e -> e < size / 2).takeWhile(e -> e < size),
                            s -> s.dropWhile(e -> e < size / 2).takeWhile(e -> e < size));
         }
     }

     /**
      * While operation type to be asserted on
      */
     enum WhileOp {
         /**
          * The takeWhile operation
          */
         Take,
         /**
          * The dropWhile operation
          */
         Drop,
         /**
          * The operation(s) are undefined
          */
         Undefined
     }

     /**
      * Create a result asserter for takeWhile or dropWhile operations.
      * <p>
      * If the stream pipeline consists of the takeWhile operation
      * ({@link WhileOp#Take}) or the dropWhile operation ({@link WhileOp#Drop})
      * then specific assertions can be made on the actual result based on the
      * input elements, {@code inputData}, and whether those elements match the
      * predicate, {@code p}, of the operation.
      * <p>
      * If the input elements have an encounter order then the actual result
      * is asserted against the result of operating sequentially on input
      * elements given the predicate and in accordance with the operation
      * semantics. (The actual result whether produced sequentially or in
      * parallel should the same.)
      * <p>
      * If the input elements have no encounter order then an actual result
      * is, for practical purposes, considered non-deterministic.
      * Consider an input list of lists that contains all possible permutations
      * of the input elements, and a output list of lists that is the result of
      * applying the pipeline with the operation sequentially to each input
      * list.
      * Any list in the output lists is a valid result. It's not practical to
      * test in such a manner.
      * For a takeWhile operation the following assertions can be made if
      * only some of the input elements match the predicate (i.e. taking will
      * short-circuit the pipeline):
      * <ol>
      * <li>The set of output elements is a subset of the set of matching
      * input elements</li>
      * <li>The set of output elements and the set of non-matching input
      * element are disjoint</li>
      * </ol>
      * For a dropWhile operation the following assertions can be made:
      * <ol>
      * <li>The set of non-matching input elements is a subset of the set of
      * output elements</li>
      * <li>The set of matching output elements is a subset of the set of
      * matching input elements</li>
      * </ol>
      *
      * @param inputData the elements input into the stream pipeline
      * @param op the operation of the stream pipeline, one of takeWhile,
      * dropWhile, or an undefined set of operations (possibly including
      * two or more takeWhile and/or dropWhile operations, or because
      * the predicate is not stateless).
      * @param p the stateless predicate applied to the operation, ignored if
      * the
      * operation is {@link WhileOp#Undefined}.
      * @param <T> the type of elements
      * @return a result asserter
      */
     private <T> ResultAsserter<Iterable<T>> whileResultAsserter(Iterable<T> inputData,
                                                                 WhileOp op,
                                                                 Predicate<? super T> p) {
         return (act, exp, ord, par) -> {
             if (par & !ord) {
                 List<T> input = new ArrayList<>();
                 inputData.forEach(input::add);

                 List<T> output = new ArrayList<>();
                 act.forEach(output::add);

                 if (op == WhileOp.Take) {
                     List<T> matchingInput = new ArrayList<>();
                     List<T> nonMatchingInput = new ArrayList<>();
                     input.forEach(t -> {
                         if (p.test(t))
                             matchingInput.add(t);
                         else
                             nonMatchingInput.add(t);
                     });

                     // If some, not all, elements are taken
                     if (matchingInput.size() < input.size()) {
                         assertTrue(output.size() <= matchingInput.size(),
                                    "Output is larger than the matching input");

                         // The output must be a subset of the matching input
                         assertTrue(matchingInput.containsAll(output),
                                    "Output is not a subset of the matching input");

                         // The output must not contain any non matching elements
                         for (T nonMatching : nonMatchingInput) {
                             assertFalse(output.contains(nonMatching),
                                         "Output and non-matching input are not disjoint");
                         }
                     }
                 }
                 else if (op == WhileOp.Drop) {
                     List<T> matchingInput = new ArrayList<>();
                     List<T> nonMatchingInput = new ArrayList<>();
                     input.forEach(t -> {
                         if (p.test(t))
                             matchingInput.add(t);
                         else
                             nonMatchingInput.add(t);
                     });

                     // The non matching input must be a subset of output
                     assertTrue(output.containsAll(nonMatchingInput),
                                "Non-matching input is not a subset of the output");

                     // The matching output must be a subset of the matching input
                     List<T> matchingOutput = new ArrayList<>();
                     output.forEach(i -> {
                         if (p.test(i))
                             matchingOutput.add(i);
                     });
                     assertTrue(matchingInput.containsAll(matchingOutput),
                                "Matching output is not a subset of matching input");
                 }

                 // Note: if there is a combination of takeWhile and dropWhile then specific
                 // assertions cannot be performed.
                 // All that can be reliably asserted is the output is a subset of the input

                 assertTrue(input.containsAll(output));
             }
             else {
                 // For specific operations derive expected result from the input
                 if (op == WhileOp.Take) {
                     List<T> takeInput = new ArrayList<>();
                     for (T t : inputData) {
                         if (p.test(t))
                             takeInput.add(t);
                         else
                             break;
                     }

                     LambdaTestHelpers.assertContents(act, takeInput);
                 }
                 else if (op == WhileOp.Drop) {
                     List<T> dropInput = new ArrayList<>();
                     for (T t : inputData) {
                         if (dropInput.size() > 0 || !p.test(t))
                             dropInput.add(t);
                     }

                     LambdaTestHelpers.assertContents(act, dropInput);
                 }

                 LambdaTestHelpers.assertContents(act, exp);
             }
         };
     }

     private Collection<Integer> sizes(int s) {
         Set<Integer> sizes = new LinkedHashSet<>();

         sizes.add(0);
         sizes.add(1);
         sizes.add(s / 4);
         sizes.add(s / 2);
         sizes.add(3 * s / 4);
         sizes.add(Math.max(0, s - 1));
         sizes.add(s);
         sizes.add(Integer.MAX_VALUE);

         return sizes;
     }

     private void testWhileMulti(TestData.OfRef<Integer> data,
                                 ResultAsserter<Iterable<Integer>> ra,
                                 Function<Stream<Integer>, Stream<Integer>> mRef,
                                 Function<IntStream, IntStream> mInt,
                                 Function<LongStream, LongStream> mLong,
                                 Function<DoubleStream, DoubleStream> mDouble) {
         Map<String, Function<Stream<Integer>, Stream<Integer>>> ms = new HashMap<>();
         ms.put("Ref", mRef);
         ms.put("Int", s -> mInt.apply(s.mapToInt(e -> e)).mapToObj(e -> e));
         ms.put("Long", s -> mLong.apply(s.mapToLong(e -> e)).mapToObj(e -> (int) e));
         ms.put("Double", s -> mDouble.apply(s.mapToDouble(e -> e)).mapToObj(e -> (int) e));
         ms.put("Ref using defaults", s -> mRef.apply(DefaultMethodStreams.delegateTo(s)));
         ms.put("Int using defaults", s -> mInt.apply(DefaultMethodStreams.delegateTo(s.mapToInt(e -> e))).mapToObj(e -> e));
         ms.put("Long using defaults", s -> mLong.apply(DefaultMethodStreams.delegateTo(s.mapToLong(e -> e))).mapToObj(e -> (int) e));
         ms.put("Double using defaults", s -> mDouble.apply(DefaultMethodStreams.delegateTo(s.mapToDouble(e -> e))).mapToObj(e -> (int) e));

         testWhileMulti(data, ra, ms);
     }

     private final void testWhileMulti(TestData.OfRef<Integer> data,
                                       ResultAsserter<Iterable<Integer>> ra,
                                       Map<String, Function<Stream<Integer>, Stream<Integer>>> ms) {
         for (Map.Entry<String, Function<Stream<Integer>, Stream<Integer>>> e : ms.entrySet()) {
             setContext("shape", e.getKey());

             withData(data)
                     .stream(e.getValue())
                     .resultAsserter(ra)
                     .exercise();
         }
     }

     @Test(groups = { "serialization-hostile" })
     public void testRefDefaultClose() {
         AtomicBoolean isClosed = new AtomicBoolean();
         Stream<Integer> s = Stream.of(1, 2, 3).onClose(() -> isClosed.set(true));
         try (Stream<Integer> ds = DefaultMethodStreams.delegateTo(s).takeWhile(e -> e < 3)) {
             ds.count();
         }
         assertTrue(isClosed.get());
     }

     @Test(groups = { "serialization-hostile" })
     public void testIntDefaultClose() {
         AtomicBoolean isClosed = new AtomicBoolean();
         IntStream s = IntStream.of(1, 2, 3).onClose(() -> isClosed.set(true));
         try (IntStream ds = DefaultMethodStreams.delegateTo(s).takeWhile(e -> e < 3)) {
             ds.count();
         }
         assertTrue(isClosed.get());
     }

     @Test(groups = { "serialization-hostile" })
     public void testLongDefaultClose() {
         AtomicBoolean isClosed = new AtomicBoolean();
         LongStream s = LongStream.of(1, 2, 3).onClose(() -> isClosed.set(true));
         try (LongStream ds = DefaultMethodStreams.delegateTo(s).takeWhile(e -> e < 3)) {
             ds.count();
         }
         assertTrue(isClosed.get());
     }

     @Test(groups = { "serialization-hostile" })
     public void testDoubleDefaultClose() {
         AtomicBoolean isClosed = new AtomicBoolean();
         DoubleStream s = DoubleStream.of(1, 2, 3).onClose(() -> isClosed.set(true));
         try (DoubleStream ds = DefaultMethodStreams.delegateTo(s).takeWhile(e -> e < 3)) {
             ds.count();
         }
         assertTrue(isClosed.get());
     }

     @Test(groups = { "serialization-hostile" })
     public void testFlatMapThenTake() {
         TestData.OfRef<Integer> range = TestData.Factory.ofSupplier(
                 "range", () -> IntStream.range(0, 100).boxed());

         exerciseOpsMulti(range,
                          // Reference result
                          s -> s.takeWhile(e -> e != 50),
                          // For other results collect into array,
                          // stream the single array (not the elements),
                          // then flat map to stream the array elements
                          s -> Stream.<Integer[]>of(s.toArray(Integer[]::new)).
                                  flatMap(Stream::of).
                                  takeWhile(e -> e != 50),
                          s -> Stream.of(s.mapToInt(e -> e).toArray()).
                                  flatMapToInt(IntStream::of).
                                  takeWhile(e -> e != 50).
                                  mapToObj(e -> e),
                          s -> Stream.of(s.mapToLong(e -> e).toArray()).
                                  flatMapToLong(LongStream::of).
                                  takeWhile(e -> e != 50L).
                                  mapToObj(e -> (int) e),
                          s -> Stream.of(s.mapToDouble(e -> e).toArray()).
                                  flatMapToDouble(DoubleStream::of).
                                  takeWhile(e -> e != 50.0).
                                  mapToObj(e -> (int) e)
                          );
     }
 }
	/*
	* Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package org.openjdk.tests.java.util.stream;

	import org.testng.annotations.Test;

	import java.util.ArrayList;
	import java.util.Collection;
	import java.util.HashMap;
	import java.util.LinkedHashSet;
	import java.util.List;
	import java.util.Map;
	import java.util.Set;
	import java.util.concurrent.atomic.AtomicBoolean;
	import java.util.function.Function;
	import java.util.function.Predicate;
	import java.util.stream.DefaultMethodStreams;
	import java.util.stream.DoubleStream;
	import java.util.stream.IntStream;
	import java.util.stream.LambdaTestHelpers;
	import java.util.stream.LongStream;
	import java.util.stream.OpTestCase;
	import java.util.stream.Stream;
	import java.util.stream.StreamTestDataProvider;
	import java.util.stream.TestData;

	/*
	* @test
	* @bug 8071597 8193856
	* @run main/timeout=240
	*/
	@Test
	public class WhileOpTest extends OpTestCase {

	@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class,
	groups = { "serialization-hostile" })
	public void testTakeWhileOps(String name, TestData.OfRef<Integer> data) {
	for (int size : sizes(data.size())) {
	setContext("takeWhile", size);

	testWhileMulti(data,
	whileResultAsserter(data, WhileOp.Take, e -> e < size),
	s -> s.takeWhile(e -> e < size),
	s -> s.takeWhile(e -> e < size),
	s -> s.takeWhile(e -> e < size),
	s -> s.takeWhile(e -> e < size));


	testWhileMulti(data,
	whileResultAsserter(data, WhileOp.Take, e -> e < size / 2),
	s -> s.takeWhile(e -> e < size).takeWhile(e -> e < size / 2),
	s -> s.takeWhile(e -> e < size).takeWhile(e -> e < size / 2),
	s -> s.takeWhile(e -> e < size).takeWhile(e -> e < size / 2),
	s -> s.takeWhile(e -> e < size).takeWhile(e -> e < size / 2));
	}
	}

	@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class,
	groups = { "serialization-hostile" })
	public void testDropWhileOps(String name, TestData.OfRef<Integer> data) {
	for (int size : sizes(data.size())) {
	setContext("dropWhile", size);

	testWhileMulti(data,
	whileResultAsserter(data, WhileOp.Drop, e -> e < size),
	s -> s.dropWhile(e -> e < size),
	s -> s.dropWhile(e -> e < size),
	s -> s.dropWhile(e -> e < size),
	s -> s.dropWhile(e -> e < size));

	testWhileMulti(data,
	whileResultAsserter(data, WhileOp.Drop, e -> e < size),
	s -> s.dropWhile(e -> e < size / 2).dropWhile(e -> e < size),
	s -> s.dropWhile(e -> e < size / 2).dropWhile(e -> e < size),
	s -> s.dropWhile(e -> e < size / 2).dropWhile(e -> e < size),
	s -> s.dropWhile(e -> e < size / 2).dropWhile(e -> e < size));
	}
	}

	@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class,
	groups = { "serialization-hostile" })
	public void testDropTakeWhileOps(String name, TestData.OfRef<Integer> data) {
	for (int size : sizes(data.size())) {
	setContext("dropWhile", size);

	testWhileMulti(data,
	whileResultAsserter(data, WhileOp.Undefined, null),
	s -> s.dropWhile(e -> e < size / 2).takeWhile(e -> e < size),
	s -> s.dropWhile(e -> e < size / 2).takeWhile(e -> e < size),
	s -> s.dropWhile(e -> e < size / 2).takeWhile(e -> e < size),
	s -> s.dropWhile(e -> e < size / 2).takeWhile(e -> e < size));
	}
	}

	/**
	* While operation type to be asserted on
	*/
	enum WhileOp {
	/**
	* The takeWhile operation
	*/
	Take,
	/**
	* The dropWhile operation
	*/
	Drop,
	/**
	* The operation(s) are undefined
	*/
	Undefined
	}

	/**
	* Create a result asserter for takeWhile or dropWhile operations.
	* <p>
	* If the stream pipeline consists of the takeWhile operation
	* ({@link WhileOp#Take}) or the dropWhile operation ({@link WhileOp#Drop})
	* then specific assertions can be made on the actual result based on the
	* input elements, {@code inputData}, and whether those elements match the
	* predicate, {@code p}, of the operation.
	* <p>
	* If the input elements have an encounter order then the actual result
	* is asserted against the result of operating sequentially on input
	* elements given the predicate and in accordance with the operation
	* semantics. (The actual result whether produced sequentially or in
	* parallel should the same.)
	* <p>
	* If the input elements have no encounter order then an actual result
	* is, for practical purposes, considered non-deterministic.
	* Consider an input list of lists that contains all possible permutations
	* of the input elements, and a output list of lists that is the result of
	* applying the pipeline with the operation sequentially to each input
	* list.
	* Any list in the output lists is a valid result. It's not practical to
	* test in such a manner.
	* For a takeWhile operation the following assertions can be made if
	* only some of the input elements match the predicate (i.e. taking will
	* short-circuit the pipeline):
	* <ol>
	* <li>The set of output elements is a subset of the set of matching
	* input elements</li>
	* <li>The set of output elements and the set of non-matching input
	* element are disjoint</li>
	* </ol>
	* For a dropWhile operation the following assertions can be made:
	* <ol>
	* <li>The set of non-matching input elements is a subset of the set of
	* output elements</li>
	* <li>The set of matching output elements is a subset of the set of
	* matching input elements</li>
	* </ol>
	*
	* @param inputData the elements input into the stream pipeline
	* @param op the operation of the stream pipeline, one of takeWhile,
	* dropWhile, or an undefined set of operations (possibly including
	* two or more takeWhile and/or dropWhile operations, or because
	* the predicate is not stateless).
	* @param p the stateless predicate applied to the operation, ignored if
	* the
	* operation is {@link WhileOp#Undefined}.
	* @param <T> the type of elements
	* @return a result asserter
	*/
	private <T> ResultAsserter<Iterable<T>> whileResultAsserter(Iterable<T> inputData,
	WhileOp op,
	Predicate<? super T> p) {
	return (act, exp, ord, par) -> {
	if (par & !ord) {
	List<T> input = new ArrayList<>();
	inputData.forEach(input::add);

	List<T> output = new ArrayList<>();
	act.forEach(output::add);

	if (op == WhileOp.Take) {
	List<T> matchingInput = new ArrayList<>();
	List<T> nonMatchingInput = new ArrayList<>();
	input.forEach(t -> {
	if (p.test(t))
	matchingInput.add(t);
	else
	nonMatchingInput.add(t);
	});

	// If some, not all, elements are taken
	if (matchingInput.size() < input.size()) {
	assertTrue(output.size() <= matchingInput.size(),
	"Output is larger than the matching input");

	// The output must be a subset of the matching input
	assertTrue(matchingInput.containsAll(output),
	"Output is not a subset of the matching input");

	// The output must not contain any non matching elements
	for (T nonMatching : nonMatchingInput) {
	assertFalse(output.contains(nonMatching),
	"Output and non-matching input are not disjoint");
	}
	}
	}
	else if (op == WhileOp.Drop) {
	List<T> matchingInput = new ArrayList<>();
	List<T> nonMatchingInput = new ArrayList<>();
	input.forEach(t -> {
	if (p.test(t))
	matchingInput.add(t);
	else
	nonMatchingInput.add(t);
	});

	// The non matching input must be a subset of output
	assertTrue(output.containsAll(nonMatchingInput),
	"Non-matching input is not a subset of the output");

	// The matching output must be a subset of the matching input
	List<T> matchingOutput = new ArrayList<>();
	output.forEach(i -> {
	if (p.test(i))
	matchingOutput.add(i);
	});
	assertTrue(matchingInput.containsAll(matchingOutput),
	"Matching output is not a subset of matching input");
	}

	// Note: if there is a combination of takeWhile and dropWhile then specific
	// assertions cannot be performed.
	// All that can be reliably asserted is the output is a subset of the input

	assertTrue(input.containsAll(output));
	}
	else {
	// For specific operations derive expected result from the input
	if (op == WhileOp.Take) {
	List<T> takeInput = new ArrayList<>();
	for (T t : inputData) {
	if (p.test(t))
	takeInput.add(t);
	else
	break;
	}

	LambdaTestHelpers.assertContents(act, takeInput);
	}
	else if (op == WhileOp.Drop) {
	List<T> dropInput = new ArrayList<>();
	for (T t : inputData) {
	if (dropInput.size() > 0 \|\| !p.test(t))
	dropInput.add(t);
	}

	LambdaTestHelpers.assertContents(act, dropInput);
	}

	LambdaTestHelpers.assertContents(act, exp);
	}
	};
	}

	private Collection<Integer> sizes(int s) {
	Set<Integer> sizes = new LinkedHashSet<>();

	sizes.add(0);
	sizes.add(1);
	sizes.add(s / 4);
	sizes.add(s / 2);
	sizes.add(3 * s / 4);
	sizes.add(Math.max(0, s - 1));
	sizes.add(s);
	sizes.add(Integer.MAX_VALUE);

	return sizes;
	}

	private void testWhileMulti(TestData.OfRef<Integer> data,
	ResultAsserter<Iterable<Integer>> ra,
	Function<Stream<Integer>, Stream<Integer>> mRef,
	Function<IntStream, IntStream> mInt,
	Function<LongStream, LongStream> mLong,
	Function<DoubleStream, DoubleStream> mDouble) {
	Map<String, Function<Stream<Integer>, Stream<Integer>>> ms = new HashMap<>();
	ms.put("Ref", mRef);
	ms.put("Int", s -> mInt.apply(s.mapToInt(e -> e)).mapToObj(e -> e));
	ms.put("Long", s -> mLong.apply(s.mapToLong(e -> e)).mapToObj(e -> (int) e));
	ms.put("Double", s -> mDouble.apply(s.mapToDouble(e -> e)).mapToObj(e -> (int) e));
	ms.put("Ref using defaults", s -> mRef.apply(DefaultMethodStreams.delegateTo(s)));
	ms.put("Int using defaults", s -> mInt.apply(DefaultMethodStreams.delegateTo(s.mapToInt(e -> e))).mapToObj(e -> e));
	ms.put("Long using defaults", s -> mLong.apply(DefaultMethodStreams.delegateTo(s.mapToLong(e -> e))).mapToObj(e -> (int) e));
	ms.put("Double using defaults", s -> mDouble.apply(DefaultMethodStreams.delegateTo(s.mapToDouble(e -> e))).mapToObj(e -> (int) e));

	testWhileMulti(data, ra, ms);
	}

	private final void testWhileMulti(TestData.OfRef<Integer> data,
	ResultAsserter<Iterable<Integer>> ra,
	Map<String, Function<Stream<Integer>, Stream<Integer>>> ms) {
	for (Map.Entry<String, Function<Stream<Integer>, Stream<Integer>>> e : ms.entrySet()) {
	setContext("shape", e.getKey());

	withData(data)
	.stream(e.getValue())
	.resultAsserter(ra)
	.exercise();
	}
	}

	@Test(groups = { "serialization-hostile" })
	public void testRefDefaultClose() {
	AtomicBoolean isClosed = new AtomicBoolean();
	Stream<Integer> s = Stream.of(1, 2, 3).onClose(() -> isClosed.set(true));
	try (Stream<Integer> ds = DefaultMethodStreams.delegateTo(s).takeWhile(e -> e < 3)) {
	ds.count();
	}
	assertTrue(isClosed.get());
	}

	@Test(groups = { "serialization-hostile" })
	public void testIntDefaultClose() {
	AtomicBoolean isClosed = new AtomicBoolean();
	IntStream s = IntStream.of(1, 2, 3).onClose(() -> isClosed.set(true));
	try (IntStream ds = DefaultMethodStreams.delegateTo(s).takeWhile(e -> e < 3)) {
	ds.count();
	}
	assertTrue(isClosed.get());
	}

	@Test(groups = { "serialization-hostile" })
	public void testLongDefaultClose() {
	AtomicBoolean isClosed = new AtomicBoolean();
	LongStream s = LongStream.of(1, 2, 3).onClose(() -> isClosed.set(true));
	try (LongStream ds = DefaultMethodStreams.delegateTo(s).takeWhile(e -> e < 3)) {
	ds.count();
	}
	assertTrue(isClosed.get());
	}

	@Test(groups = { "serialization-hostile" })
	public void testDoubleDefaultClose() {
	AtomicBoolean isClosed = new AtomicBoolean();
	DoubleStream s = DoubleStream.of(1, 2, 3).onClose(() -> isClosed.set(true));
	try (DoubleStream ds = DefaultMethodStreams.delegateTo(s).takeWhile(e -> e < 3)) {
	ds.count();
	}
	assertTrue(isClosed.get());
	}

	@Test(groups = { "serialization-hostile" })
	public void testFlatMapThenTake() {
	TestData.OfRef<Integer> range = TestData.Factory.ofSupplier(
	"range", () -> IntStream.range(0, 100).boxed());

	exerciseOpsMulti(range,
	// Reference result
	s -> s.takeWhile(e -> e != 50),
	// For other results collect into array,
	// stream the single array (not the elements),
	// then flat map to stream the array elements
	s -> Stream.<Integer[]>of(s.toArray(Integer[]::new)).
	flatMap(Stream::of).
	takeWhile(e -> e != 50),
	s -> Stream.of(s.mapToInt(e -> e).toArray()).
	flatMapToInt(IntStream::of).
	takeWhile(e -> e != 50).
	mapToObj(e -> e),
	s -> Stream.of(s.mapToLong(e -> e).toArray()).
	flatMapToLong(LongStream::of).
	takeWhile(e -> e != 50L).
	mapToObj(e -> (int) e),
	s -> Stream.of(s.mapToDouble(e -> e).toArray()).
	flatMapToDouble(DoubleStream::of).
	takeWhile(e -> e != 50.0).
	mapToObj(e -> (int) e)
	);
	}
	}