Class IdentityProcessorVerification<T>

java.lang.Object

org.reactivestreams.tck.WithHelperPublisher<T>

org.reactivestreams.tck.IdentityProcessorVerification<T>

All Implemented Interfaces:

PublisherVerificationRules, SubscriberWhiteboxVerificationRules

Direct Known Subclasses:

IdentityFlowProcessorVerification

public abstract class IdentityProcessorVerification<T>
extends WithHelperPublisher<T>
implements SubscriberWhiteboxVerificationRules, PublisherVerificationRules

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	IdentityProcessorVerification.ManualSubscriberWithErrorCollection<A>
class	IdentityProcessorVerification.TestSetup

Field Summary

Fields

Modifier and Type	Field	Description
private final TestEnvironment	env
private final int	processorBufferSize	/////////////// END OF DELEGATED TO SPECS //////////////////
private final PublisherVerification<T>	publisherVerification
private final SubscriberWhiteboxVerification<T>	subscriberVerification	/////////////////// DELEGATED TO SPECS //////////////////////

Constructor Summary

Constructors

Constructor	Description
IdentityProcessorVerification(TestEnvironment env)	Test class must specify the expected time it takes for the publisher to shut itself down when the the last downstream Subscription is cancelled.
IdentityProcessorVerification(TestEnvironment env, long publisherReferenceGCTimeoutMillis)	Test class must specify the expected time it takes for the publisher to shut itself down when the the last downstream Subscription is cancelled.
IdentityProcessorVerification(TestEnvironment env, long publisherReferenceGCTimeoutMillis, int processorBufferSize)	Test class must specify the expected time it takes for the publisher to shut itself down when the the last downstream Subscription is cancelled.

Method Summary

Modifier and Type	Method	Description
long	boundedDepthOfOnNextAndRequestRecursion()	In order to verify rule 3.3 of the reactive streams spec, this number will be used to check if a Subscription actually solves the "unbounded recursion" problem by not allowing the number of recursive calls to exceed the number returned by this method.
abstract Publisher<T>	createFailedPublisher()	By implementing this method, additional TCK tests concerning a "failed" publishers will be run.
abstract Processor<T,T>	createIdentityProcessor(int bufferSize)	This is the main method you must implement in your test incarnation.
Publisher<T>	createPublisher(long elements)	/////////////////// PUBLISHER RULES VERIFICATION ///////////////////////////
Subscriber<T>	createSubscriber(SubscriberWhiteboxVerification.WhiteboxSubscriberProbe<T> probe)	/////////////////// SUBSCRIBER RULES VERIFICATION ///////////////////////////
boolean	doesCoordinatedEmission()	Override this method and return true if the Processor returned by the createIdentityProcessor(int) coordinates its Subscribers request amounts and only delivers onNext signals if all Subscribers have indicated (via their Subscription#request(long)) they are ready to receive elements.
long	maxElementsFromPublisher()	Override and return lower value if your Publisher is only able to produce a known number of elements.
long	maxSupportedSubscribers()	Describes the tested implementation in terms of how many subscribers they can support.
void	mustImmediatelyPassOnOnErrorEventsReceivedFromItsUpstreamToItsDownstream()	/////////////////// OTHER RULE VERIFICATION ///////////////////////////
void	notVerified()	//////////////////// TEST INFRASTRUCTURE //////////////////////
void	notVerified(String message)
void	optional_spec104_mustSignalOnErrorWhenFails()	Asks for an error Publisher that should call onSubscribe exactly once followed by a single call to onError() without receiving any requests and otherwise not throwing any exception.
void	optional_spec105_emptyStreamMustTerminateBySignallingOnComplete()	Asks for an empty Publisher (i.e., length 0) and verifies it completes in a timely manner.
void	optional_spec111_maySupportMultiSubscribe()	Asks for a single-element Publisher and subscribes to it twice, without consuming with either Subscriber instance (i.e., no requests are issued).
void	optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingManyUpfront()	Asks for a short Publisher (length 3), subscribes 3 Subscribers to it, requests more than the length items upfront with each and verifies they all received the same items in the same order (but does not verify they all complete).
void	optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingManyUpfrontAndCompleteAsExpected()	Asks for a short Publisher (length 3), subscribes 3 Subscribers to it, requests more than the length items upfront with each and verifies they all received the same items in the same order followed by an onComplete signal.
void	optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingOneByOne()	Asks for a short Publisher (length 5), subscribes 3 Subscribers to it, requests with different patterns and checks if all 3 received the same events in the same order.
void	optional_spec111_registeredSubscribersMustReceiveOnNextOrOnCompleteSignals()	Asks for a single-element Publisher and subscribes to it twice.
void	optional_spec309_requestNegativeNumberMaySignalIllegalArgumentExceptionWithSpecificMessage()	Asks for a short Publisher (length 10) and issues a random, negative request() call which should trigger an onError call with an IllegalArgumentException.
void	optionalMultipleSubscribersTest(long requiredSubscribersSupport, Function<Long, IdentityProcessorVerification<T>.TestSetup> body)	Test for feature that REQUIRES multiple subscribers to be supported by Publisher.
void	required_createPublisher1MustProduceAStreamOfExactly1Element()	//////////////////// DELEGATED TESTS, A PROCESSOR "IS A" PUBLISHER //////////////////////
void	required_createPublisher3MustProduceAStreamOfExactly3Elements()	Asks for a Publisher that should emit exactly three items and complete (all within a timeout specified by TestEnvironment.defaultTimeoutMillis()).
void	required_exerciseWhiteboxHappyPath()	//////////////////// DELEGATED TESTS, A PROCESSOR "IS A" SUBSCRIBER //////////////////////
void	required_mustRequestFromUpstreamForElementsThatHaveBeenRequestedLongAgo()	Asks for a Processor that supports at least 2 Subscribers at once and checks requests from Subscribers will eventually lead to requests towards the upstream of the Processor.
void	required_spec101_subscriptionRequestMustResultInTheCorrectNumberOfProducedElements()	Asks for a Publisher that responds to a request pattern of 0 (not requesting upfront), 1, 1 and 2 in a timely manner.
void	required_spec102_maySignalLessThanRequestedAndTerminateSubscription()	Asks for a short Publisher and verifies that requesting once and with more than the length (but bounded) results in the correct number of items to be emitted (i.e., length 3 and request 10) followed by an onComplete signal.
void	required_spec104_mustCallOnErrorOnAllItsSubscribersIfItEncountersANonRecoverableError()	Asks for a Processor that supports at least 2 Subscribers at once and checks if two Subscribers receive the same items and a terminal Exception.
void	required_spec105_mustSignalOnCompleteWhenFiniteStreamTerminates()	Asks for a short Publisher (i.e., length 3) and verifies, after requesting one by one, the sequence completes normally.
void	required_spec107_mustNotEmitFurtherSignalsOnceOnCompleteHasBeenSignalled()	Asks for a single-element Publisher and checks if requesting after the terminal event doesn't lead to more items or terminal signals to be emitted.
void	required_spec109_mayRejectCallsToSubscribeIfPublisherIsUnableOrUnwillingToServeThemRejectionMustTriggerOnErrorAfterOnSubscribe()	Asks for an error Publisher that should call onSubscribe exactly once followed by a single call to onError() without receiving any requests.
void	required_spec109_mustIssueOnSubscribeForNonNullSubscriber()	Asks for an empty Publisher and verifies if onSubscribe signal was emitted before any other onNext, onError or onComplete signal.
void	required_spec109_subscribeThrowNPEOnNullSubscriber()	Asks for an empty Publisher and calls subscribe on it with null that should result in a NullPointerException to be thrown.
void	required_spec201_mustSignalDemandViaSubscriptionRequest()
void	required_spec203_mustNotCallMethodsOnSubscriptionOrPublisherInOnComplete()
void	required_spec203_mustNotCallMethodsOnSubscriptionOrPublisherInOnError()
void	required_spec205_mustCallSubscriptionCancelIfItAlreadyHasAnSubscriptionAndReceivesAnotherOnSubscribeSignal()
void	required_spec208_mustBePreparedToReceiveOnNextSignalsAfterHavingCalledSubscriptionCancel()
void	required_spec209_mustBePreparedToReceiveAnOnCompleteSignalWithoutPrecedingRequestCall()
void	required_spec209_mustBePreparedToReceiveAnOnCompleteSignalWithPrecedingRequestCall()
void	required_spec210_mustBePreparedToReceiveAnOnErrorSignalWithoutPrecedingRequestCall()
void	required_spec210_mustBePreparedToReceiveAnOnErrorSignalWithPrecedingRequestCall()
void	required_spec213_onError_mustThrowNullPointerExceptionWhenParametersAreNull()
void	required_spec213_onNext_mustThrowNullPointerExceptionWhenParametersAreNull()
void	required_spec213_onSubscribe_mustThrowNullPointerExceptionWhenParametersAreNull()
void	required_spec302_mustAllowSynchronousRequestCallsFromOnNextAndOnSubscribe()	Asks for a short Publisher (length 6), requests several times from within onSubscribe and then requests one-by-one from onNext.
void	required_spec303_mustNotAllowUnboundedRecursion()	Asks for a Publisher with length equal to the value returned by PublisherVerificationRules.required_validate_boundedDepthOfOnNextAndRequestRecursion() plus 1, calls request(1) externally and then from within onNext and checks if the stack depth did not increase beyond the amount permitted by PublisherVerificationRules.required_validate_boundedDepthOfOnNextAndRequestRecursion().
void	required_spec306_afterSubscriptionIsCancelledRequestMustBeNops()	Asks for a short Publisher (length 3) and verifies that cancelling without requesting anything, then requesting items should result in no signals to be emitted.
void	required_spec307_afterSubscriptionIsCancelledAdditionalCancelationsMustBeNops()	Asks for a single-element Publisher and verifies that without requesting anything, cancelling the sequence multiple times should result in no signals to be emitted and should result in an thrown exception.
void	required_spec308_requestMustRegisterGivenNumberElementsToBeProduced()
void	required_spec309_requestNegativeNumberMustSignalIllegalArgumentException()	Asks for a short Publisher (length 10) and issues a random, negative request() call which should trigger an onError call with an IllegalArgumentException.
void	required_spec309_requestZeroMustSignalIllegalArgumentException()	Asks for a short Publisher (length 10) and issues a request(0) which should trigger an onError call with an IllegalArgumentException.
void	required_spec312_cancelMustMakeThePublisherToEventuallyStopSignaling()	Asks for a short Publisher (length 20), requests some items (less than the length), consumes one item then cancels the sequence and verifies the publisher emitted at most the requested amount and stopped emitting (or terminated).
void	required_spec313_cancelMustMakeThePublisherEventuallyDropAllReferencesToTheSubscriber()	Asks for a short Publisher (length 3) requests and consumes one element from it, cancels the Subscription , calls System.gc() and then checks if all references to the test Subscriber has been dropped (by checking the WeakReference has been emptied).
void	required_spec317_mustNotSignalOnErrorWhenPendingAboveLongMaxValue()	Asks for a very long Publisher (up to Integer.MAX_VALUE), requests Long.MAX_VALUE - 1 after each received item and expects no failure due to a potential overflow in the pending emission count while consuming 10 items and cancelling the sequence.
void	required_spec317_mustSupportACumulativePendingElementCountUpToLongMaxValue()	Asks for a short Publisher (length 3) and requests Long.MAX_VALUE from it in total (split across two Long.MAX_VALUE / 2 and one request(1)), verifying that the Publisher emits all of its items and completes normally.
void	required_spec317_mustSupportAPendingElementCountUpToLongMaxValue()	Asks for a short Publisher (length 3) and requests Long.MAX_VALUE from it, verifying that the Publisher emits all of its items and completes normally and does not keep spinning attempting to fulfill the Long.MAX_VALUE demand by some means.
void	required_validate_boundedDepthOfOnNextAndRequestRecursion()	Validates that the override of PublisherVerification.boundedDepthOfOnNextAndRequestRecursion() returns a positive value.
void	required_validate_maxElementsFromPublisher()	Validates that the override of PublisherVerification.maxElementsFromPublisher() returns a non-negative value.
void	setUp()	/////////////////// TEST ENV CLEANUP /////////////////////////////////////
boolean	skipStochasticTests()	Override and return true in order to skip executing tests marked as Stochastic.
void	stochastic_spec103_mustSignalOnMethodsSequentially()	Asks for a short Publisher (i.e., length 10), repeatedly subscribes to this Publisher, requests items one by one and verifies the Publisher calls the onXXX methods non-overlappingly.
void	untested_spec106_mustConsiderSubscriptionCancelledAfterOnErrorOrOnCompleteHasBeenCalled()	Currently, this test is skipped because it is unclear this rule can be effectively checked on a Publisher instance without looking into or hooking into the implementation of it.
void	untested_spec107_mustNotEmitFurtherSignalsOnceOnErrorHasBeenSignalled()	Currently, this test is skipped, although it is possible to validate an error Publisher along the same lines as PublisherVerificationRules.required_spec107_mustNotEmitFurtherSignalsOnceOnCompleteHasBeenSignalled().
void	untested_spec108_possiblyCanceledSubscriptionShouldNotReceiveOnErrorOrOnCompleteSignals()	Currently, this test is skipped because there was no agreement on how to verify its "eventually" requirement.
void	untested_spec109_subscribeShouldNotThrowNonFatalThrowable()	Currently, this test is skipped because there is no common agreement on what is to be considered a fatal exception and besides, Publisher.subscribe is only allowed throw a NullPointerException and any other exception would require looking into or hooking into the implementation of the Publisher.
void	untested_spec110_rejectASubscriptionRequestIfTheSameSubscriberSubscribesTwice()	Currently, this test is skipped because enforcing rule §1.10 requires unlimited retention and reference-equal checks on all incoming Subscriber which is generally infeasible, plus reusing the same Subscriber instance is better detected (or ignored) inside Subscriber.onSubscribe when the method is called multiple times.
void	untested_spec202_shouldAsynchronouslyDispatch()
void	untested_spec204_mustConsiderTheSubscriptionAsCancelledInAfterRecievingOnCompleteOrOnError()
void	untested_spec206_mustCallSubscriptionCancelIfItIsNoLongerValid()
void	untested_spec207_mustEnsureAllCallsOnItsSubscriptionTakePlaceFromTheSameThreadOrTakeCareOfSynchronization()
void	untested_spec211_mustMakeSureThatAllCallsOnItsMethodsHappenBeforeTheProcessingOfTheRespectiveEvents()
void	untested_spec212_mustNotCallOnSubscribeMoreThanOnceBasedOnObjectEquality_specViolation()
void	untested_spec213_failingOnSignalInvocation()
void	untested_spec301_mustNotBeCalledOutsideSubscriberContext()
void	untested_spec304_requestShouldNotPerformHeavyComputations()	Currently, this test is skipped because a request could enter into a synchronous computation via onNext legally and otherwise there is no common agreement how to detect such heavy computation reliably.
void	untested_spec305_cancelMustNotSynchronouslyPerformHeavyComputation()	Currently, this test is skipped because there is no reliable agreed upon way to detect a heavy computation.
void	untested_spec310_requestMaySynchronouslyCallOnNextOnSubscriber()
void	untested_spec311_requestMaySynchronouslyCallOnCompleteOrOnError()
void	untested_spec314_cancelMayCauseThePublisherToShutdownIfNoOtherSubscriptionExists()
void	untested_spec315_cancelMustNotThrowExceptionAndMustSignalOnError()
void	untested_spec316_requestMustNotThrowExceptionAndMustOnErrorTheSubscriber()

Methods inherited from class WithHelperPublisher

createElement, createHelperPublisher, publisherExecutorService

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

env

private final TestEnvironment env

subscriberVerification

private final SubscriberWhiteboxVerification<T> subscriberVerification

/////////////////// DELEGATED TO SPECS //////////////////////

publisherVerification

private final PublisherVerification<T> publisherVerification

processorBufferSize

private final int processorBufferSize

/////////////// END OF DELEGATED TO SPECS //////////////////

Constructor Details

IdentityProcessorVerification

public IdentityProcessorVerification(TestEnvironment env)

Test class must specify the expected time it takes for the publisher to shut itself down when the the last downstream Subscription is cancelled. The processor will be required to be able to buffer TestEnvironment.TEST_BUFFER_SIZE elements.

IdentityProcessorVerification

public IdentityProcessorVerification(TestEnvironment env,
 long publisherReferenceGCTimeoutMillis)

Test class must specify the expected time it takes for the publisher to shut itself down when the the last downstream Subscription is cancelled. The processor will be required to be able to buffer TestEnvironment.TEST_BUFFER_SIZE elements.

Parameters:

publisherReferenceGCTimeoutMillis - used to determine after how much time a reference to a Subscriber should be already dropped by the Publisher.

IdentityProcessorVerification

public IdentityProcessorVerification(TestEnvironment env,
 long publisherReferenceGCTimeoutMillis,
 int processorBufferSize)

Test class must specify the expected time it takes for the publisher to shut itself down when the the last downstream Subscription is cancelled.

Parameters:

publisherReferenceGCTimeoutMillis - used to determine after how much time a reference to a Subscriber should be already dropped by the Publisher.

processorBufferSize - number of elements the processor is required to be able to buffer.

Method Details

createIdentityProcessor

public abstract Processor<T,T> createIdentityProcessor(int bufferSize)

This is the main method you must implement in your test incarnation. It must create a Processor, which simply forwards all stream elements from its upstream to its downstream. It must be able to internally buffer the given number of elements.

Parameters:

bufferSize - number of elements the processor is required to be able to buffer.

createFailedPublisher

public abstract Publisher<T> createFailedPublisher()

By implementing this method, additional TCK tests concerning a "failed" publishers will be run. The expected behaviour of the Publisher returned by this method is hand out a subscription, followed by signalling onError on it, as specified by Rule 1.9. If you want to ignore these additional tests, return null from this method.

maxElementsFromPublisher

public long maxElementsFromPublisher()

Override and return lower value if your Publisher is only able to produce a known number of elements. For example, if it is designed to return at-most-one element, return 1 from this method. Defaults to Long.MAX_VALUE - 1, meaning that the Publisher can be produce a huge but NOT an unbounded number of elements. To mark your Publisher will *never* signal an onComplete override this method and return Long.MAX_VALUE, which will result in *skipping all tests which require an onComplete to be triggered* (!).

boundedDepthOfOnNextAndRequestRecursion

public long boundedDepthOfOnNextAndRequestRecursion()

In order to verify rule 3.3 of the reactive streams spec, this number will be used to check if a Subscription actually solves the "unbounded recursion" problem by not allowing the number of recursive calls to exceed the number returned by this method.

See Also:

• reactive streams spec, rule 3.3
• PublisherVerification.required_spec303_mustNotAllowUnboundedRecursion()

skipStochasticTests

public boolean skipStochasticTests()

Override and return true in order to skip executing tests marked as Stochastic. Stochastic in this case means that the Rule is impossible or infeasible to deterministically verify— usually this means that this test case can yield false positives ("be green") even if for some case, the given implementation may violate the tested behaviour.

maxSupportedSubscribers

public long maxSupportedSubscribers()

Describes the tested implementation in terms of how many subscribers they can support. Some tests require the Publisher under test to support multiple Subscribers, yet the spec does not require all publishers to be able to do so, thus – if an implementation supports only a limited number of subscribers (e.g. only 1 subscriber, also known as "no fanout") you MUST return that number from this method by overriding it.

doesCoordinatedEmission

public boolean doesCoordinatedEmission()

Override this method and return true if the Processor returned by the createIdentityProcessor(int) coordinates its Subscribers request amounts and only delivers onNext signals if all Subscribers have indicated (via their Subscription#request(long)) they are ready to receive elements.

setUp

@BeforeMethod
public void setUp()
           throws Exception

/////////////////// TEST ENV CLEANUP /////////////////////////////////////

Throws:

Exception

createPublisher

public Publisher<T> createPublisher(long elements)

/////////////////// PUBLISHER RULES VERIFICATION ///////////////////////////

required_validate_maxElementsFromPublisher

public void required_validate_maxElementsFromPublisher()
                                                throws Exception

Description copied from interface: PublisherVerificationRules

Validates that the override of PublisherVerification.maxElementsFromPublisher() returns a non-negative value.

Specified by:

required_validate_maxElementsFromPublisher in interface PublisherVerificationRules

Throws:

Exception

required_validate_boundedDepthOfOnNextAndRequestRecursion

public void required_validate_boundedDepthOfOnNextAndRequestRecursion()
                                                               throws Exception

Description copied from interface: PublisherVerificationRules

Validates that the override of PublisherVerification.boundedDepthOfOnNextAndRequestRecursion() returns a positive value.

Specified by:

required_validate_boundedDepthOfOnNextAndRequestRecursion in interface PublisherVerificationRules

Throws:

Exception

required_createPublisher1MustProduceAStreamOfExactly1Element

public void required_createPublisher1MustProduceAStreamOfExactly1Element()
                                                                  throws Throwable

//////////////////// DELEGATED TESTS, A PROCESSOR "IS A" PUBLISHER //////////////////////

Specified by:

required_createPublisher1MustProduceAStreamOfExactly1Element in interface PublisherVerificationRules

Throws:

Throwable

required_createPublisher3MustProduceAStreamOfExactly3Elements

public void required_createPublisher3MustProduceAStreamOfExactly3Elements()
                                                                   throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a Publisher that should emit exactly three items and complete (all within a timeout specified by TestEnvironment.defaultTimeoutMillis()).

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 3.

The tests requests one-by-one and verifies each single response item arrives in time.

If this test fails, the following could be checked within the Publisher implementation:

• the Publisher.subscribe(Subscriber) method has actual implementation,
• in the Publisher.subscribe(Subscriber) method, if there is an upstream Publisher, that Publisher is actually subscribed to,
• if the Publisher is part of a chain, all elements actually issue a request() call in response to the test subscriber or by default to their upstream,
• in the Publisher.subscribe(Subscriber) method, the Subscriber.onSubscribe is called as part of the preparation process (usually before subscribing to other Publishers),
• if the Publisher implementation works for a subscriber that calls request(1) after consuming an item,
• if the Publisher implementation is able to emit an onComplete without requests.

Specified by:

required_createPublisher3MustProduceAStreamOfExactly3Elements in interface PublisherVerificationRules

Throws:

Throwable

required_spec101_subscriptionRequestMustResultInTheCorrectNumberOfProducedElements

public void required_spec101_subscriptionRequestMustResultInTheCorrectNumberOfProducedElements()
                                                                                        throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a Publisher that responds to a request pattern of 0 (not requesting upfront), 1, 1 and 2 in a timely manner.

Verifies rule: 1.1

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 5.

This test ensures that the Publisher implementation correctly responds to request() calls that in total are less than the number of elements this Publisher could emit (thus the completion event won't be emitted).

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• if the Publisher implementation considers the cumulative request amount it receives,
• if the Publisher doesn't lose any request() signal and the state transition from idle -> emitting or emitting -> keep emitting works properly.

Specified by:

required_spec101_subscriptionRequestMustResultInTheCorrectNumberOfProducedElements in interface PublisherVerificationRules

Throws:

Throwable

required_spec102_maySignalLessThanRequestedAndTerminateSubscription

public void required_spec102_maySignalLessThanRequestedAndTerminateSubscription()
                                                                         throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher and verifies that requesting once and with more than the length (but bounded) results in the correct number of items to be emitted (i.e., length 3 and request 10) followed by an onComplete signal.

Verifies rule: 1.2

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 3.

This test ensures that the Publisher implementation can deal with larger requests than the number of items it can produce.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass.

Specified by:

required_spec102_maySignalLessThanRequestedAndTerminateSubscription in interface PublisherVerificationRules

Throws:

Throwable

stochastic_spec103_mustSignalOnMethodsSequentially

public void stochastic_spec103_mustSignalOnMethodsSequentially()
                                                        throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (i.e., length 10), repeatedly subscribes to this Publisher, requests items one by one and verifies the Publisher calls the onXXX methods non-overlappingly.

Verifies rule: 1.3

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 10.

Note that this test is probabilistic, that is, may not capture any concurrent invocation in a {code Publisher} implementation. Note also that this test is sensitive to cases when a request() call in onSubscribe() triggers an asynchronous call to the other onXXX methods. In contrast, the test allows synchronous call chain of onSubscribe -> request -> onNext.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• if a request() call from onSubscribe() could trigger an asynchronous call to onNext() and if so, make sure such request() calls are deferred until the call to onSubscribe() returns normally.

Specified by:

stochastic_spec103_mustSignalOnMethodsSequentially in interface PublisherVerificationRules

Throws:

Throwable

optional_spec104_mustSignalOnErrorWhenFails

public void optional_spec104_mustSignalOnErrorWhenFails()
                                                 throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for an error Publisher that should call onSubscribe exactly once followed by a single call to onError() without receiving any requests and otherwise not throwing any exception.

Verifies rule: 1.4

The test is not executed if PublisherVerification.createErrorPublisher() returns null.

If this test fails, the following could be checked within the error Publisher implementation:

• the Publisher.subscribe(Subscriber) method has actual implementation,
• in the Publisher.subscribe(Subscriber) method, if there is an upstream Publisher, that Publisher is actually subscribed to,
• if the Publisher implementation does signal an onSubscribe before signalling onError,
• if the Publisher implementation is able to emit an onError without requests,
• if the Publisher is non-empty as this test requires a Publisher to signal an onError eagerly.

Specified by:

optional_spec104_mustSignalOnErrorWhenFails in interface PublisherVerificationRules

Throws:

Throwable

required_spec105_mustSignalOnCompleteWhenFiniteStreamTerminates

public void required_spec105_mustSignalOnCompleteWhenFiniteStreamTerminates()
                                                                     throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (i.e., length 3) and verifies, after requesting one by one, the sequence completes normally.

Verifies rule: 1.5

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 3.

Note that the tests requests 1 after the items have been received and before expecting an onComplete signal.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,

Specified by:

required_spec105_mustSignalOnCompleteWhenFiniteStreamTerminates in interface PublisherVerificationRules

Throws:

Throwable

optional_spec105_emptyStreamMustTerminateBySignallingOnComplete

public void optional_spec105_emptyStreamMustTerminateBySignallingOnComplete()
                                                                     throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for an empty Publisher (i.e., length 0) and verifies it completes in a timely manner.

Verifies rule: 1.5

Note that the tests requests 1 before expecting an onComplete signal.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• if the Publisher is non-empty as this test requires a Publisher without items.

Specified by:

optional_spec105_emptyStreamMustTerminateBySignallingOnComplete in interface PublisherVerificationRules

Throws:

Throwable

untested_spec106_mustConsiderSubscriptionCancelledAfterOnErrorOrOnCompleteHasBeenCalled

public void untested_spec106_mustConsiderSubscriptionCancelledAfterOnErrorOrOnCompleteHasBeenCalled()
                                                                                             throws Throwable

Description copied from interface: PublisherVerificationRules

Currently, this test is skipped because it is unclear this rule can be effectively checked on a Publisher instance without looking into or hooking into the implementation of it.

Verifies rule: 1.6

Specified by:

untested_spec106_mustConsiderSubscriptionCancelledAfterOnErrorOrOnCompleteHasBeenCalled in interface PublisherVerificationRules

Throws:

Throwable

required_spec107_mustNotEmitFurtherSignalsOnceOnCompleteHasBeenSignalled

public void required_spec107_mustNotEmitFurtherSignalsOnceOnCompleteHasBeenSignalled()
                                                                              throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a single-element Publisher and checks if requesting after the terminal event doesn't lead to more items or terminal signals to be emitted.

Verifies rule: 1.7

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 1.

The tests requests more items than the expected Publisher length upfront and some more items after its completion.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• the indication for the terminal state is properly persisted and a request call can't trigger emission of more items or another terminal signal.

Specified by:

required_spec107_mustNotEmitFurtherSignalsOnceOnCompleteHasBeenSignalled in interface PublisherVerificationRules

Throws:

Throwable

untested_spec107_mustNotEmitFurtherSignalsOnceOnErrorHasBeenSignalled

public void untested_spec107_mustNotEmitFurtherSignalsOnceOnErrorHasBeenSignalled()
                                                                           throws Throwable

Description copied from interface: PublisherVerificationRules

Currently, this test is skipped, although it is possible to validate an error Publisher along the same lines as PublisherVerificationRules.required_spec107_mustNotEmitFurtherSignalsOnceOnCompleteHasBeenSignalled().

Verifies rule: 1.7

Specified by:

untested_spec107_mustNotEmitFurtherSignalsOnceOnErrorHasBeenSignalled in interface PublisherVerificationRules

Throws:

Throwable

untested_spec108_possiblyCanceledSubscriptionShouldNotReceiveOnErrorOrOnCompleteSignals

public void untested_spec108_possiblyCanceledSubscriptionShouldNotReceiveOnErrorOrOnCompleteSignals()
                                                                                             throws Throwable

Description copied from interface: PublisherVerificationRules

Currently, this test is skipped because there was no agreement on how to verify its "eventually" requirement.

Verifies rule: 1.8

Specified by:

untested_spec108_possiblyCanceledSubscriptionShouldNotReceiveOnErrorOrOnCompleteSignals in interface PublisherVerificationRules

Throws:

Throwable

untested_spec109_subscribeShouldNotThrowNonFatalThrowable

public void untested_spec109_subscribeShouldNotThrowNonFatalThrowable()
                                                               throws Throwable

Description copied from interface: PublisherVerificationRules

Currently, this test is skipped because there is no common agreement on what is to be considered a fatal exception and besides, Publisher.subscribe is only allowed throw a NullPointerException and any other exception would require looking into or hooking into the implementation of the Publisher.

Verifies rule: 1.9

Specified by:

untested_spec109_subscribeShouldNotThrowNonFatalThrowable in interface PublisherVerificationRules

Throws:

Throwable

required_spec109_subscribeThrowNPEOnNullSubscriber

public void required_spec109_subscribeThrowNPEOnNullSubscriber()
                                                        throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for an empty Publisher and calls subscribe on it with null that should result in a NullPointerException to be thrown.

Verifies rule: 1.9

If this test fails, check if the subscribe() implementation has an explicit null check (or a method dereference on the Subscriber), especially if the incoming Subscriber is wrapped or stored to be used later.

Specified by:

required_spec109_subscribeThrowNPEOnNullSubscriber in interface PublisherVerificationRules

Throws:

Throwable

required_spec109_mayRejectCallsToSubscribeIfPublisherIsUnableOrUnwillingToServeThemRejectionMustTriggerOnErrorAfterOnSubscribe

public void required_spec109_mayRejectCallsToSubscribeIfPublisherIsUnableOrUnwillingToServeThemRejectionMustTriggerOnErrorAfterOnSubscribe()
                                                                                                                                    throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for an error Publisher that should call onSubscribe exactly once followed by a single call to onError() without receiving any requests.

Verifies rule: 1.9

The test is not executed if PublisherVerification.createErrorPublisher() returns null.

The difference between this test and PublisherVerificationRules.optional_spec104_mustSignalOnErrorWhenFails() is that there is no explicit verification if exceptions were thrown in addition to the regular onSubscribe+onError signal pair.

If this test fails, the following could be checked within the error Publisher implementation:

• the Publisher.subscribe(Subscriber) method has actual implementation,
• in the Publisher.subscribe(Subscriber) method, if there is an upstream Publisher, that Publisher is actually subscribed to,
• if the Publisher implementation is able to emit an onError without requests,
• if the Publisher is non-empty as this test expects a Publisher without items.

Specified by:

required_spec109_mayRejectCallsToSubscribeIfPublisherIsUnableOrUnwillingToServeThemRejectionMustTriggerOnErrorAfterOnSubscribe in interface PublisherVerificationRules

Throws:

Throwable

required_spec109_mustIssueOnSubscribeForNonNullSubscriber

public void required_spec109_mustIssueOnSubscribeForNonNullSubscriber()
                                                               throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for an empty Publisher and verifies if onSubscribe signal was emitted before any other onNext, onError or onComplete signal.

Verifies rule: 1.9

Note that this test doesn't request anything, however, an onNext is not considered as a failure.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• the Publisher.subscribe(Subscriber) method has actual implementation,
• in the Publisher.subscribe(Subscriber) method, if there is an upstream Publisher, that Publisher is actually subscribed to,
• in the Publisher.subscribe(Subscriber) method, the Subscriber.onSubscribe is called as part of the preparation process (usually before subscribing to other Publishers).

Specified by:

required_spec109_mustIssueOnSubscribeForNonNullSubscriber in interface PublisherVerificationRules

Throws:

Throwable

untested_spec110_rejectASubscriptionRequestIfTheSameSubscriberSubscribesTwice

public void untested_spec110_rejectASubscriptionRequestIfTheSameSubscriberSubscribesTwice()
                                                                                   throws Throwable

Description copied from interface: PublisherVerificationRules

Currently, this test is skipped because enforcing rule §1.10 requires unlimited retention and reference-equal checks on all incoming Subscriber which is generally infeasible, plus reusing the same Subscriber instance is better detected (or ignored) inside Subscriber.onSubscribe when the method is called multiple times.

Verifies rule: 1.10

Specified by:

untested_spec110_rejectASubscriptionRequestIfTheSameSubscriberSubscribesTwice in interface PublisherVerificationRules

Throws:

Throwable

optional_spec111_maySupportMultiSubscribe

public void optional_spec111_maySupportMultiSubscribe()
                                               throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a single-element Publisher and subscribes to it twice, without consuming with either Subscriber instance (i.e., no requests are issued).

Verifies rule: 1.11

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 1.

Note that this test ignores what signals the Publisher emits. Any exception thrown through non-regular means will indicate a skipped test.

Specified by:

optional_spec111_maySupportMultiSubscribe in interface PublisherVerificationRules

Throws:

Throwable

optional_spec111_registeredSubscribersMustReceiveOnNextOrOnCompleteSignals

public void optional_spec111_registeredSubscribersMustReceiveOnNextOrOnCompleteSignals()
                                                                                throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a single-element Publisher and subscribes to it twice. Each Subscriber requests for 1 element and checks if onNext or onComplete signals was received.

Verifies rule: 1.11, and depends on valid implementation of rule 1.5 in order to verify this.

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 1.

Any exception thrown through non-regular means will indicate a skipped test.

Specified by:

optional_spec111_registeredSubscribersMustReceiveOnNextOrOnCompleteSignals in interface PublisherVerificationRules

Throws:

Throwable

optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingOneByOne

public void optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingOneByOne()
                                                                                                                       throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 5), subscribes 3 Subscribers to it, requests with different patterns and checks if all 3 received the same events in the same order.

Verifies rule: 1.11

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 5.

The request pattern for the first Subscriber is (1, 1, 2, 1); for the second is (2, 3) and for the third is (3, 1, 1).

Note that this test requires a Publisher that always emits the same signals to any Subscriber, regardless of when they subscribe and how they request elements. I.e., a "live" Publisher emitting the current time would not pass this test.

Note that this test is optional and may appear skipped even if the behavior should be actually supported by the Publisher, see the skip message for an indication of this.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• if the Publisher implementation considers the cumulative request amount it receives,
• if the Publisher doesn't lose any request() signal and the state transition from idle -> emitting or emitting -> keep emitting works properly.

Specified by:

optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingOneByOne in interface PublisherVerificationRules

Throws:

Throwable

optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingManyUpfront

public void optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingManyUpfront()
                                                                                                                          throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 3), subscribes 3 Subscribers to it, requests more than the length items upfront with each and verifies they all received the same items in the same order (but does not verify they all complete).

Verifies rule: 1.11

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 3.

Note that this test requires a Publisher that always emits the same signals to any Subscriber, regardless of when they subscribe and how they request elements. I.e., a "live" Publisher emitting the current time would not pass this test.

Note that this test is optional and may appear skipped even if the behavior should be actually supported by the Publisher, see the skip message for an indication of this.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• if the Publisher implementation considers the cumulative request amount it receives,
• if the Publisher doesn't lose any request() signal and the state transition from idle -> emitting or emitting -> keep emitting works properly.

Specified by:

optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingManyUpfront in interface PublisherVerificationRules

Throws:

Throwable

optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingManyUpfrontAndCompleteAsExpected

public void optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingManyUpfrontAndCompleteAsExpected()
                                                                                                                                               throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 3), subscribes 3 Subscribers to it, requests more than the length items upfront with each and verifies they all received the same items in the same order followed by an onComplete signal.

Verifies rule: 1.11

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 3.

Note that this test requires a Publisher that always emits the same signals to any Subscriber, regardless of when they subscribe and how they request elements. I.e., a "live" Publisher emitting the current time would not pass this test.

Note that this test is optional and may appear skipped even if the behavior should be actually supported by the Publisher, see the skip message for an indication of this.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• if the Publisher implementation considers the cumulative request amount it receives,
• if the Publisher doesn't lose any request() signal and the state transition from idle -> emitting or emitting -> keep emitting works properly.

Specified by:

optional_spec111_multicast_mustProduceTheSameElementsInTheSameSequenceToAllOfItsSubscribersWhenRequestingManyUpfrontAndCompleteAsExpected in interface PublisherVerificationRules

Throws:

Throwable

required_spec302_mustAllowSynchronousRequestCallsFromOnNextAndOnSubscribe

public void required_spec302_mustAllowSynchronousRequestCallsFromOnNextAndOnSubscribe()
                                                                               throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 6), requests several times from within onSubscribe and then requests one-by-one from onNext.

Verifies rule: 3.2

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 6.

The request pattern is 3 x 1 from within onSubscribe and one from within each onNext invocation.

The test consumes the Publisher but otherwise doesn't verify the Publisher completes (however, it checks for errors).

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• if the Publisher implementation considers the cumulative request amount it receives,
• if the Publisher doesn't lose any request() signal and the state transition from idle -> emitting or emitting -> keep emitting works properly.

Specified by:

required_spec302_mustAllowSynchronousRequestCallsFromOnNextAndOnSubscribe in interface PublisherVerificationRules

Throws:

Throwable

required_spec303_mustNotAllowUnboundedRecursion

public void required_spec303_mustNotAllowUnboundedRecursion()
                                                     throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a Publisher with length equal to the value returned by PublisherVerificationRules.required_validate_boundedDepthOfOnNextAndRequestRecursion() plus 1, calls request(1) externally and then from within onNext and checks if the stack depth did not increase beyond the amount permitted by PublisherVerificationRules.required_validate_boundedDepthOfOnNextAndRequestRecursion().

Verifies rule: 3.3

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than PublisherVerificationRules.required_validate_boundedDepthOfOnNextAndRequestRecursion() plus 1.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• the implementation doesn't allow unbounded recursion when request() is called from within onNext, i.e., the lack of reentrant-safe state machine around the request amount (such as a for loop with a bound on the parameter n that calls onNext).

Specified by:

required_spec303_mustNotAllowUnboundedRecursion in interface PublisherVerificationRules

Throws:

Throwable

untested_spec304_requestShouldNotPerformHeavyComputations

public void untested_spec304_requestShouldNotPerformHeavyComputations()
                                                               throws Exception

Description copied from interface: PublisherVerificationRules

Currently, this test is skipped because a request could enter into a synchronous computation via onNext legally and otherwise there is no common agreement how to detect such heavy computation reliably.

Verifies rule: 3.4

Specified by:

untested_spec304_requestShouldNotPerformHeavyComputations in interface PublisherVerificationRules

Throws:

Exception

untested_spec305_cancelMustNotSynchronouslyPerformHeavyComputation

public void untested_spec305_cancelMustNotSynchronouslyPerformHeavyComputation()
                                                                        throws Exception

Description copied from interface: PublisherVerificationRules

Currently, this test is skipped because there is no reliable agreed upon way to detect a heavy computation.

Verifies rule: 3.5

Specified by:

untested_spec305_cancelMustNotSynchronouslyPerformHeavyComputation in interface PublisherVerificationRules

Throws:

Exception

required_spec306_afterSubscriptionIsCancelledRequestMustBeNops

public void required_spec306_afterSubscriptionIsCancelledRequestMustBeNops()
                                                                    throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 3) and verifies that cancelling without requesting anything, then requesting items should result in no signals to be emitted.

Verifies rule: 3.6

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 3.

The post-cancellation request pattern is (1, 1, 1).

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• the cancellation indicator flag is properly persisted (may require volatile) and checked as part of the signal emission process.

Specified by:

required_spec306_afterSubscriptionIsCancelledRequestMustBeNops in interface PublisherVerificationRules

Throws:

Throwable

required_spec307_afterSubscriptionIsCancelledAdditionalCancelationsMustBeNops

public void required_spec307_afterSubscriptionIsCancelledAdditionalCancelationsMustBeNops()
                                                                                   throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a single-element Publisher and verifies that without requesting anything, cancelling the sequence multiple times should result in no signals to be emitted and should result in an thrown exception.

Verifies rule: 3.7

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 1.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• the cancellation indicator flag is properly persisted (may require volatile) and checked as part of the signal emission process.

Specified by:

required_spec307_afterSubscriptionIsCancelledAdditionalCancelationsMustBeNops in interface PublisherVerificationRules

Throws:

Throwable

required_spec309_requestZeroMustSignalIllegalArgumentException

public void required_spec309_requestZeroMustSignalIllegalArgumentException()
                                                                    throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 10) and issues a request(0) which should trigger an onError call with an IllegalArgumentException.

Verifies rule: 3.9

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 10.

Note that this test expects the IllegalArgumentException being signalled through onError, not by throwing from request() (which is also forbidden) or signalling the error by any other means (i.e., through the Thread.currentThread().getUncaughtExceptionHandler() for example).

Note also that requesting and emission may happen concurrently and honoring this rule may require extra coordination within the Publisher.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• the Publisher can emit an onError in this particular case, even if there was no prior and legal request call and even if the Publisher would like to emit items first before emitting an onError in general.

Specified by:

required_spec309_requestZeroMustSignalIllegalArgumentException in interface PublisherVerificationRules

Throws:

Throwable

required_spec309_requestNegativeNumberMustSignalIllegalArgumentException

public void required_spec309_requestNegativeNumberMustSignalIllegalArgumentException()
                                                                              throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 10) and issues a random, negative request() call which should trigger an onError call with an IllegalArgumentException.

Verifies rule: 3.9

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 10.

Note that this test expects the IllegalArgumentException being signalled through onError, not by throwing from request() (which is also forbidden) or signalling the error by any other means (i.e., through the Thread.currentThread().getUncaughtExceptionHandler() for example).

Note also that requesting and emission may happen concurrently and honoring this rule may require extra coordination within the Publisher.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• the Publisher can emit an onError in this particular case, even if there was no prior and legal request call and even if the Publisher would like to emit items first before emitting an onError in general.

Specified by:

required_spec309_requestNegativeNumberMustSignalIllegalArgumentException in interface PublisherVerificationRules

Throws:

Throwable

optional_spec309_requestNegativeNumberMaySignalIllegalArgumentExceptionWithSpecificMessage

public void optional_spec309_requestNegativeNumberMaySignalIllegalArgumentExceptionWithSpecificMessage()
                                                                                                throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 10) and issues a random, negative request() call which should trigger an onError call with an IllegalArgumentException.

Verifies rule: 3.9

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 10.

Note that this test expects the IllegalArgumentException being signalled through onError, not by throwing from request() (which is also forbidden) or signalling the error by any other means (i.e., through the Thread.currentThread().getUncaughtExceptionHandler() for example).

Note also that requesting and emission may happen concurrently and honoring this rule may require extra coordination within the Publisher.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• the Publisher can emit an onError in this particular case, even if there was no prior and legal request call and even if the Publisher would like to emit items first before emitting an onError in general.

Specified by:

optional_spec309_requestNegativeNumberMaySignalIllegalArgumentExceptionWithSpecificMessage in interface PublisherVerificationRules

Throws:

Throwable

required_spec312_cancelMustMakeThePublisherToEventuallyStopSignaling

public void required_spec312_cancelMustMakeThePublisherToEventuallyStopSignaling()
                                                                          throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 20), requests some items (less than the length), consumes one item then cancels the sequence and verifies the publisher emitted at most the requested amount and stopped emitting (or terminated).

Verifies rule: 3.12

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 20.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• the cancellation indicator flag is properly persisted (may require volatile) and checked as part of the signal emission process.

Specified by:

required_spec312_cancelMustMakeThePublisherToEventuallyStopSignaling in interface PublisherVerificationRules

Throws:

Throwable

required_spec313_cancelMustMakeThePublisherEventuallyDropAllReferencesToTheSubscriber

public void required_spec313_cancelMustMakeThePublisherEventuallyDropAllReferencesToTheSubscriber()
                                                                                           throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 3) requests and consumes one element from it, cancels the Subscription , calls System.gc() and then checks if all references to the test Subscriber has been dropped (by checking the WeakReference has been emptied).

Verifies rule: 3.13

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 3.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• the cancellation indicator flag is properly persisted (may require volatile) and checked as part of the signal emission process.
• the Publisher stores the Subscriber reference somewhere which is then not cleaned up when the Subscriber is cancelled. Note that this may happen on many code paths in a Publisher, for example in an emission loop that terminates because of the cancel signal or because reaching a terminal state. Note also that eagerly nulling Subscriber references may not be necessary for this test to pass in case there is a self-contained chain of them (i.e., Publisher.subscribe() creates a chain of fresh Subscriber instances where each of them only references their downstream Subscriber thus the chain can get GC'd when the reference to the final Subscriber is dropped).

Specified by:

required_spec313_cancelMustMakeThePublisherEventuallyDropAllReferencesToTheSubscriber in interface PublisherVerificationRules

Throws:

Throwable

required_spec317_mustSupportAPendingElementCountUpToLongMaxValue

public void required_spec317_mustSupportAPendingElementCountUpToLongMaxValue()
                                                                      throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 3) and requests Long.MAX_VALUE from it, verifying that the Publisher emits all of its items and completes normally and does not keep spinning attempting to fulfill the Long.MAX_VALUE demand by some means.

Verifies rule: 3.17

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 3.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• if the Publisher implementation considers the cumulative request amount it receives,
• if the Publisher doesn't lose any request() signal and the state transition from idle -> emitting or emitting -> keep emitting works properly.

Specified by:

required_spec317_mustSupportAPendingElementCountUpToLongMaxValue in interface PublisherVerificationRules

Throws:

Throwable

required_spec317_mustSupportACumulativePendingElementCountUpToLongMaxValue

public void required_spec317_mustSupportACumulativePendingElementCountUpToLongMaxValue()
                                                                                throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a short Publisher (length 3) and requests Long.MAX_VALUE from it in total (split across two Long.MAX_VALUE / 2 and one request(1)), verifying that the Publisher emits all of its items and completes normally.

Verifies rule: 3.17

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than 3.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• if the Publisher implementation considers the cumulative request amount it receives,
• if the Publisher implements adding individual request amounts together properly (not overflowing into zero or negative pending request amounts) or not properly deducing the number of emitted items from the pending amount,
• if the Publisher doesn't lose any request() signal and the state transition from idle -> emitting or emitting -> keep emitting works properly.

Specified by:

required_spec317_mustSupportACumulativePendingElementCountUpToLongMaxValue in interface PublisherVerificationRules

Throws:

Throwable

required_spec317_mustNotSignalOnErrorWhenPendingAboveLongMaxValue

public void required_spec317_mustNotSignalOnErrorWhenPendingAboveLongMaxValue()
                                                                       throws Throwable

Description copied from interface: PublisherVerificationRules

Asks for a very long Publisher (up to Integer.MAX_VALUE), requests Long.MAX_VALUE - 1 after each received item and expects no failure due to a potential overflow in the pending emission count while consuming 10 items and cancelling the sequence.

Verifies rule: 3.17

The test is not executed if PublisherVerification.maxElementsFromPublisher() is less than Integer.MAX_VALUE.

The request pattern is one request(1) upfront and ten request(Long.MAX_VALUE - 1) after.

If this test fails, the following could be checked within the Publisher implementation:

• the TestEnvironment has large enough timeout specified in case the Publisher has some time-delay behavior,
• make sure the PublisherVerificationRules.required_createPublisher1MustProduceAStreamOfExactly1Element() and PublisherVerificationRules.required_createPublisher3MustProduceAStreamOfExactly3Elements() tests pass,
• if the Publisher implementation considers the cumulative request amount it receives,
• if the Publisher implements adding individual request amounts together properly (not overflowing into zero or negative pending request amounts) or not properly deducing the number of emitted items from the pending amount,
• if the Publisher doesn't lose any request() signal and the state transition from idle -> emitting or emitting -> keep emitting works properly.

Specified by:

required_spec317_mustNotSignalOnErrorWhenPendingAboveLongMaxValue in interface PublisherVerificationRules

Throws:

Throwable

required_spec104_mustCallOnErrorOnAllItsSubscribersIfItEncountersANonRecoverableError

public void required_spec104_mustCallOnErrorOnAllItsSubscribersIfItEncountersANonRecoverableError()
                                                                                           throws Throwable

Asks for a Processor that supports at least 2 Subscribers at once and checks if two Subscribers receive the same items and a terminal Exception.

If the Processor requests and/or emits items only when all of its Subscribers have requested, override doesCoordinatedEmission() and return true to indicate this property.

Verifies rule: 1.4 with multiple Subscribers.

The test is not executed if maxSupportedSubscribers() is less than 2.

If this test fails, the following could be checked within the Processor implementation:

• The TestEnvironment has large enough timeout specified in case the Processor has some time-delay behavior.
• The Processor is able to fulfill requests of its Subscribers independently of each other's requests or else override doesCoordinatedEmission() and return true to indicate the test Subscribers both have to request first.

Throws:

Throwable

createSubscriber

public Subscriber<T> createSubscriber(SubscriberWhiteboxVerification.WhiteboxSubscriberProbe<T> probe)

/////////////////// SUBSCRIBER RULES VERIFICATION ///////////////////////////

mustImmediatelyPassOnOnErrorEventsReceivedFromItsUpstreamToItsDownstream

public void mustImmediatelyPassOnOnErrorEventsReceivedFromItsUpstreamToItsDownstream()
                                                                              throws Exception

/////////////////// OTHER RULE VERIFICATION ///////////////////////////

Throws:

Exception

required_exerciseWhiteboxHappyPath

public void required_exerciseWhiteboxHappyPath()
                                        throws Throwable

//////////////////// DELEGATED TESTS, A PROCESSOR "IS A" SUBSCRIBER //////////////////////

Specified by:

required_exerciseWhiteboxHappyPath in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

required_spec201_mustSignalDemandViaSubscriptionRequest

public void required_spec201_mustSignalDemandViaSubscriptionRequest()
                                                             throws Throwable

Specified by:

required_spec201_mustSignalDemandViaSubscriptionRequest in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

untested_spec202_shouldAsynchronouslyDispatch

public void untested_spec202_shouldAsynchronouslyDispatch()
                                                   throws Exception

Specified by:

untested_spec202_shouldAsynchronouslyDispatch in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

required_spec203_mustNotCallMethodsOnSubscriptionOrPublisherInOnComplete

public void required_spec203_mustNotCallMethodsOnSubscriptionOrPublisherInOnComplete()
                                                                              throws Throwable

Specified by:

required_spec203_mustNotCallMethodsOnSubscriptionOrPublisherInOnComplete in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

required_spec203_mustNotCallMethodsOnSubscriptionOrPublisherInOnError

public void required_spec203_mustNotCallMethodsOnSubscriptionOrPublisherInOnError()
                                                                           throws Throwable

Specified by:

required_spec203_mustNotCallMethodsOnSubscriptionOrPublisherInOnError in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

untested_spec204_mustConsiderTheSubscriptionAsCancelledInAfterRecievingOnCompleteOrOnError

public void untested_spec204_mustConsiderTheSubscriptionAsCancelledInAfterRecievingOnCompleteOrOnError()
                                                                                                throws Exception

Specified by:

untested_spec204_mustConsiderTheSubscriptionAsCancelledInAfterRecievingOnCompleteOrOnError in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

required_spec205_mustCallSubscriptionCancelIfItAlreadyHasAnSubscriptionAndReceivesAnotherOnSubscribeSignal

public void required_spec205_mustCallSubscriptionCancelIfItAlreadyHasAnSubscriptionAndReceivesAnotherOnSubscribeSignal()
                                                                                                                throws Throwable

Specified by:

required_spec205_mustCallSubscriptionCancelIfItAlreadyHasAnSubscriptionAndReceivesAnotherOnSubscribeSignal in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

untested_spec206_mustCallSubscriptionCancelIfItIsNoLongerValid

public void untested_spec206_mustCallSubscriptionCancelIfItIsNoLongerValid()
                                                                    throws Exception

Specified by:

untested_spec206_mustCallSubscriptionCancelIfItIsNoLongerValid in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

untested_spec207_mustEnsureAllCallsOnItsSubscriptionTakePlaceFromTheSameThreadOrTakeCareOfSynchronization

public void untested_spec207_mustEnsureAllCallsOnItsSubscriptionTakePlaceFromTheSameThreadOrTakeCareOfSynchronization()
                                                                                                               throws Exception

Specified by:

untested_spec207_mustEnsureAllCallsOnItsSubscriptionTakePlaceFromTheSameThreadOrTakeCareOfSynchronization in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

required_spec208_mustBePreparedToReceiveOnNextSignalsAfterHavingCalledSubscriptionCancel

public void required_spec208_mustBePreparedToReceiveOnNextSignalsAfterHavingCalledSubscriptionCancel()
                                                                                              throws Throwable

Specified by:

required_spec208_mustBePreparedToReceiveOnNextSignalsAfterHavingCalledSubscriptionCancel in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

required_spec209_mustBePreparedToReceiveAnOnCompleteSignalWithPrecedingRequestCall

public void required_spec209_mustBePreparedToReceiveAnOnCompleteSignalWithPrecedingRequestCall()
                                                                                        throws Throwable

Specified by:

required_spec209_mustBePreparedToReceiveAnOnCompleteSignalWithPrecedingRequestCall in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

required_spec209_mustBePreparedToReceiveAnOnCompleteSignalWithoutPrecedingRequestCall

public void required_spec209_mustBePreparedToReceiveAnOnCompleteSignalWithoutPrecedingRequestCall()
                                                                                           throws Throwable

Specified by:

required_spec209_mustBePreparedToReceiveAnOnCompleteSignalWithoutPrecedingRequestCall in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

required_spec210_mustBePreparedToReceiveAnOnErrorSignalWithPrecedingRequestCall

public void required_spec210_mustBePreparedToReceiveAnOnErrorSignalWithPrecedingRequestCall()
                                                                                     throws Throwable

Specified by:

required_spec210_mustBePreparedToReceiveAnOnErrorSignalWithPrecedingRequestCall in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

required_spec210_mustBePreparedToReceiveAnOnErrorSignalWithoutPrecedingRequestCall

public void required_spec210_mustBePreparedToReceiveAnOnErrorSignalWithoutPrecedingRequestCall()
                                                                                        throws Throwable

Specified by:

required_spec210_mustBePreparedToReceiveAnOnErrorSignalWithoutPrecedingRequestCall in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

untested_spec211_mustMakeSureThatAllCallsOnItsMethodsHappenBeforeTheProcessingOfTheRespectiveEvents

public void untested_spec211_mustMakeSureThatAllCallsOnItsMethodsHappenBeforeTheProcessingOfTheRespectiveEvents()
                                                                                                         throws Exception

Specified by:

untested_spec211_mustMakeSureThatAllCallsOnItsMethodsHappenBeforeTheProcessingOfTheRespectiveEvents in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

untested_spec212_mustNotCallOnSubscribeMoreThanOnceBasedOnObjectEquality_specViolation

public void untested_spec212_mustNotCallOnSubscribeMoreThanOnceBasedOnObjectEquality_specViolation()
                                                                                            throws Throwable

Specified by:

untested_spec212_mustNotCallOnSubscribeMoreThanOnceBasedOnObjectEquality_specViolation in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

untested_spec213_failingOnSignalInvocation

public void untested_spec213_failingOnSignalInvocation()
                                                throws Exception

Specified by:

untested_spec213_failingOnSignalInvocation in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

required_spec213_onSubscribe_mustThrowNullPointerExceptionWhenParametersAreNull

public void required_spec213_onSubscribe_mustThrowNullPointerExceptionWhenParametersAreNull()
                                                                                     throws Throwable

Specified by:

required_spec213_onSubscribe_mustThrowNullPointerExceptionWhenParametersAreNull in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

required_spec213_onNext_mustThrowNullPointerExceptionWhenParametersAreNull

public void required_spec213_onNext_mustThrowNullPointerExceptionWhenParametersAreNull()
                                                                                throws Throwable

Specified by:

required_spec213_onNext_mustThrowNullPointerExceptionWhenParametersAreNull in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

required_spec213_onError_mustThrowNullPointerExceptionWhenParametersAreNull

public void required_spec213_onError_mustThrowNullPointerExceptionWhenParametersAreNull()
                                                                                 throws Throwable

Specified by:

required_spec213_onError_mustThrowNullPointerExceptionWhenParametersAreNull in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

untested_spec301_mustNotBeCalledOutsideSubscriberContext

public void untested_spec301_mustNotBeCalledOutsideSubscriberContext()
                                                              throws Exception

Specified by:

untested_spec301_mustNotBeCalledOutsideSubscriberContext in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

required_spec308_requestMustRegisterGivenNumberElementsToBeProduced

public void required_spec308_requestMustRegisterGivenNumberElementsToBeProduced()
                                                                         throws Throwable

Specified by:

required_spec308_requestMustRegisterGivenNumberElementsToBeProduced in interface SubscriberWhiteboxVerificationRules

Throws:

Throwable

untested_spec310_requestMaySynchronouslyCallOnNextOnSubscriber

public void untested_spec310_requestMaySynchronouslyCallOnNextOnSubscriber()
                                                                    throws Exception

Specified by:

untested_spec310_requestMaySynchronouslyCallOnNextOnSubscriber in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

untested_spec311_requestMaySynchronouslyCallOnCompleteOrOnError

public void untested_spec311_requestMaySynchronouslyCallOnCompleteOrOnError()
                                                                     throws Exception

Specified by:

untested_spec311_requestMaySynchronouslyCallOnCompleteOrOnError in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

untested_spec314_cancelMayCauseThePublisherToShutdownIfNoOtherSubscriptionExists

public void untested_spec314_cancelMayCauseThePublisherToShutdownIfNoOtherSubscriptionExists()
                                                                                      throws Exception

Specified by:

untested_spec314_cancelMayCauseThePublisherToShutdownIfNoOtherSubscriptionExists in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

untested_spec315_cancelMustNotThrowExceptionAndMustSignalOnError

public void untested_spec315_cancelMustNotThrowExceptionAndMustSignalOnError()
                                                                      throws Exception

Specified by:

untested_spec315_cancelMustNotThrowExceptionAndMustSignalOnError in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

untested_spec316_requestMustNotThrowExceptionAndMustOnErrorTheSubscriber

public void untested_spec316_requestMustNotThrowExceptionAndMustOnErrorTheSubscriber()
                                                                              throws Exception

Specified by:

untested_spec316_requestMustNotThrowExceptionAndMustOnErrorTheSubscriber in interface SubscriberWhiteboxVerificationRules

Throws:

Exception

required_mustRequestFromUpstreamForElementsThatHaveBeenRequestedLongAgo

public void required_mustRequestFromUpstreamForElementsThatHaveBeenRequestedLongAgo()
                                                                             throws Throwable

Asks for a Processor that supports at least 2 Subscribers at once and checks requests from Subscribers will eventually lead to requests towards the upstream of the Processor.

If the Processor requests and/or emits items only when all of its Subscribers have requested, override doesCoordinatedEmission() and return true to indicate this property.

Verifies rule: 2.1 with multiple Subscribers.

The test is not executed if maxSupportedSubscribers() is less than 2.

If this test fails, the following could be checked within the Processor implementation:

• The TestEnvironment has large enough timeout specified in case the Processor has some time-delay behavior.
• The Processor is able to fulfill requests of its Subscribers independently of each other's requests or else override doesCoordinatedEmission() and return true to indicate the test Subscribers both have to request first.

Throws:

Throwable

notVerified

public void notVerified()

//////////////////// TEST INFRASTRUCTURE //////////////////////

notVerified

public void notVerified(String message)

optionalMultipleSubscribersTest

public void optionalMultipleSubscribersTest(long requiredSubscribersSupport,
 Function<Long, IdentityProcessorVerification<T>.TestSetup> body)
                                     throws Throwable

Test for feature that REQUIRES multiple subscribers to be supported by Publisher.

Throws:

Throwable