Changelog for dejafu-1.0.0.1

Release Notes

All notable changes to this project will be documented in this file.

This project is versioned according to the Package Versioning Policy, the de facto standard Haskell versioning scheme.

1.0.0.1

Date 2017-01-19
Git tag dejafu-1.0.0.1
Hackage https://hackage.haskell.org/package/dejafu-1.0.0.1

Miscellaneous

The upper bound on concurrency was bumped to <1.5.

1.0.0.0

Date 2017-12-23
Git tag dejafu-1.0.0.0
Hackage https://hackage.haskell.org/package/dejafu-1.0.0.0

Test.DejaFu

All testing functions now require a MonadConc, MonadRef, and MonadIO constraint:

It is no longer possible to test things in ST.
All testing functions now take the action to test as the last parameter.
The autocheckIO, dejafuIO, dejafusIO, autocheckWayIO, dejafuWayIO, dejafusWayIO, dejafuDiscardIO, runTestM, and runTestWayM functions are now gone.
The Predicate type has been replaced with a more general ProPredicate type which is a profunctor and (b) can discard results not needed to determine if the predicate passes. (#124)

All testing functions have been generalised to take a ProPredicate instead. The Predicate a type remains as an alias for ProPredicate a a. Passing tests have their resident memory usage significantly decreased.
The Result type no longer includes a number of cases checked, as this is not meaningful with predicates including discard functions.
New alwaysNothing and somewhereNothing functions, like alwaysTrue and somewhereTrue, to lift functions to ProPredicates.
The alwaysTrue2 function is gone, as its behaviour was unintuitive and easy to get wrong, and has been replaced with new alwaysSameOn and alwaysSameBy predicates, which generalise alwaysSame.
The alwaysSame, alwaysSameOn, and alwaysSameBy predicates now gives the simplest execution trace leading to each distinct result.

Test.DejaFu.Common

This module has been split up into new Test.DejaFu.Internal, Types, and Utils modules. (#155)
New ForkOS and IsCurrentThreadBound thread actions. (#126)
New WillForkOS and WillIsCurrentThreadBound lookaheads. (#126)
The TTrace type synonym for [TAction] has been removed.
The preEmpCount function has been removed.
New functions strengthenDiscard and weakenDiscard to combine discard functions.
The Discard type is now defined here and re-exported from Test.DejaFu.SCT.
The ThreadId, CRefId, MVarId, and TVarId types are now newtypes over a common Id type. (#137)

Test.DejaFu.Conc

The ConcST type alias is gone.
The MonadBase IO ConcIO instance is gone.
The MonadIO ConcIO instance is replaces with a more general MonadIO n => MonadIO (ConcT r n) instance.
The runConcurrent function now has a MonadConc constraint.
If bound threads are supported, the main thread when testing is bound. (#126)
Each entry in an execution trace is now in the form (decision, alternatives, action). The chosen thread is no longer in the list of alternatives, which makes raw traces easier to read. (#121)
Due to changes in Test.DejaFu.Schedule, no longer re-exports Decision, NonEmpty, tidOf, or decisionOf.

Test.DejaFu.Refinement

A blocking interference function is no longer reported as a deadlocking execution.

Test.DejaFu.Schedule

No longer re-exports Decision or NonEmpty.
The tidOf and decisionOf functions have moved to Test.DejaFu.Utils.

Test.DejaFu.SCT

All testing functions now require a MonadConc constraint:

It is no longer possible to test things in ST.

Test.DejaFu.STM

This is now an internal module. (#155)

Performance

Significant resident memory reduction for most passing tests.
Improved dependency detection for MVar actions, leading to fewer executions.

Miscellaneous

The minimum supported version of concurrency is now 1.3.0.0.

0.9.1.2

Date 2017-12-12
Git tag dejafu-0.9.1.2
Hackage https://hackage.haskell.org/package/dejafu-0.9.1.2

Miscellaneous

The upper bound on leancheck was bumped to <0.8.

0.9.1.1

Date 2017-12-08
Git tag dejafu-0.9.1.1
Hackage https://hackage.haskell.org/package/dejafu-0.9.1.1

Miscellaneous

Fix an issue where nested masks nested inside unmasks would sometimes not be pre-empted in systematic testing.

0.9.1.0

Date 2017-11-26
Git tag dejafu-0.9.1.0
Hackage https://hackage.haskell.org/package/dejafu-0.9.1.0

Test.DejaFu.Common

Fix some incorrect "@since" haddock comments.
Pretty-printed traces now display a pre-emption following a yield with a little "p".

Test.DejaFu.Conc

Add a missing MonadFail instance.

Test.DejaFu.STM

Add a missing MonadFail instance.

0.9.0.3

Date 2017-11-06
Git tag dejafu-0.9.0.3
Hackage https://hackage.haskell.org/package/dejafu-0.9.0.3

Miscellaneous

Impose a dependency between commits and memory barriers, to make barriers sound (#138).

0.9.0.2

Date 2017-11-02
Git tag dejafu-0.9.0.2
Hackage https://hackage.haskell.org/package/dejafu-0.9.0.2

Miscellaneous

Small improvement to dependency detection of STM transactions.
A fair bound of 0 will now prevent all yields.

0.9.0.1

Date 2017-10-28
Git tag dejafu-0.9.0.1
Hackage https://hackage.haskell.org/package/dejafu-0.9.0.1

Miscellaneous

Fixed an issue where tests with exception handlers would sometimes skip over nested handlers or try to take the tail of an empty list (#139 and #141).

0.9.0.0

Date 2017-10-11
Git tag dejafu-0.9.0.0
Hackage https://hackage.haskell.org/package/dejafu-0.9.0.0

Test.DejaFu.Common

New isInternalError, isAbort, isDeadlock, isUncaughtException, and isIllegalSubconcurrency functions for matching failure types. Also exported from Test.DejaFu.
The UncaughtException Failure constructor now includes the exception.

The Read, Enum, and Bounded instances are gone. The Eq, Ord, and NFData instances use the show of the exception. Pretty-printed failures include the exception text.
New ThreadDelay and WillThreadDelay constructors in ThreadAction and Lookahead. Uses of threadDelay are no longer reported as a use of yield.

0.8.0.0

Date 2017-09-26
Git tag dejafu-0.8.0.0
Hackage https://hackage.haskell.org/package/dejafu-0.8.0.0

Test.DejaFu.Common

Execution traces now only include a single item of lookahead (#120).
STM traces now include IDs of created TVars (#80).

Test.DejaFu.Schedule

Schedulers no longer take the execution trace so far (#106).
The Scheduler type is now a newtype (#122).

0.7.3.0

Date 2017-09-26
Git tag dejafu-0.7.3.0
Hackage https://hackage.haskell.org/package/dejafu-0.7.3.0

Test.DejaFu.Common

A new function threadNames, to get all named threads from a trace.

Miscellaneous

Escaping a mask by raising an exception now correctly restores the masking state (#118).
Named threads which are only started by a pre-emption now show up in the trace (#101).

0.7.2.0

Date 2017-09-16
Git tag dejafu-0.7.2.0
Hackage https://hackage.haskell.org/package/dejafu-0.7.2.0

Test.DejaFu.STM

The STM n r monad now has Alternative and MonadPlus instances, using orElse for the binary operation and retry for the unit.

Miscellaneous

The Eq instance for ThreadId, CRefId, MVarId, and TVarId now only compares the numbers, not the names.

This makes it consistent with the Ord instances, and is also a small performance gain.
Now compatible with concurrency-1.2.0.0.

0.7.1.3

Date 2017-09-08
Git tag dejafu-0.7.1.3
Hackage https://hackage.haskell.org/package/dejafu-0.7.1.3

Miscellaneous

Aborted STM transactions are now rolled back correctly (issue #111).
Slightly improved run-time of systematic testing.

0.7.1.2

Date 2017-08-21
Git tag dejafu-0.7.1.2
Hackage https://hackage.haskell.org/package/dejafu-0.7.1.2

Miscellaneous

Errors thrown with Control.Monad.fail no longer terminate testing, and are now correctly treated as asynchronous exceptions.

0.7.1.1

Date 2017-08-16
Git tag dejafu-0.7.1.1
Hackage https://hackage.haskell.org/package/dejafu-0.7.1.1

Miscellaneous

Significantly reduced memory usage in systematic testing when discarding traces.

Previously this was O(max trace length * number of executions)

Now it's O(max trace length + total size of traces kept)

0.7.1.0

Date 2017-08-10
Git tag dejafu-0.7.1.0
Hackage https://hackage.haskell.org/package/dejafu-0.7.1.0

Test.DejaFu

Exposed the new SCT discard functions through dejafuDiscard and dejafuDiscardIO.

There are no dejafusDiscard and dejafusDiscardIO functions because this would probably be confusing, as the traces are shared.
The Discard type and defaultDiscard function are also exposed.

Test.DejaFu.Defaults

Added a new defaultDiscarder function, which discards nothing.

Test.DejaFu.SCT

Added new SCT functions to selectively discard results or traces, which can be a significant memory saving if you know what sorts of results you are interested in:
- New type: Discard.
- New functions: runSCTDiscard, resultsSetDiscard, sctBoundDiscard, sctUniformRandomDiscard, and sctWeightedRandomDiscard.
- resultsSet and resultsSet' now discard traces as they are produced, rather than all at the end, greatly improving performance when traces are large.

0.7.0.2

Date 2017-06-12
Git tag dejafu-0.7.0.2
Hackage https://hackage.haskell.org/package/dejafu-0.7.0.2

Test.DejaFu.Refinement

Removed unnecessary typeclass constraints from check, check', checkFor, and counterExamples.

Miscellaneous

Removed an unnecessary dependency on monad-loops.

0.7.0.1

Date 2017-06-09
Git tag dejafu-0.7.0.1
Hackage https://hackage.haskell.org/package/dejafu-0.7.0.1

Test.DejaFu.Refinement

check, check', and checkFor are now faster if there are multiple counterexamples.
The above and counterExamples are now faster even if there is only a single counterexample in some cases.

0.7.0.0

Date 2017-06-07
Git tag dejafu-0.7.0.0
Hackage https://hackage.haskell.org/package/dejafu-0.7.0.0

Test.DejaFu

The new Test.DejaFu.Defaults and Test.DejaFu.Refinement modules are re-exported.
The new smart constructors from Test.DejaFu.SCT are exported.

Test.DejaFu.Defaults

The default* values are now defined in the new Test.DejaFu.Defaults module. There is no breaking API change as they are re-exported from Test.DejaFu.

Test.DejaFu.Refinement

A new module for checking observational properties of the side-effects of stateful, concurrent functions.

This is related to my work on CoCo, allowing dejafu to test what CoCo discovers.

Test.DejaFu.SCT

The Way type is now abstract and exposes smart constructor functions:
- systematically, corresponding to the old Systematically.
- randomly, corresponding to the old Randomly,
- uniformly, a new uniform random (as opposed to weighted random) scheduler.
- swarmy, corresponding to the old Randomly and specifying how many executions to use the same weights for.
A new sctUniformRandom function to do uniform (non-weighted) scheduling.
The sctRandom function is now called sctWeightedRandom and can now re-use the same weights for multiple executions.
The sctPreBound, sctFairBound, and sctLengthBound functions have been removed.

Fixed

An issue where subconcurrency would re-use MVar IDs, leading to false reports of deadlock on occasion (issue #81).

0.6.0.0

Date 2017-04-08
Git tag dejafu-0.6.0.0
Hackage https://hackage.haskell.org/package/dejafu-0.6.0.0

Test.DejaFu.Conc

The Conc n r a type is now ConcT r n a, and has been given a MonadTrans instance. Uses of lift appear in the execution trace in the same way as liftBase and liftIO.
- The ConcIO and ConcST aliases have been updated, so this should be an invisible change to most users.

Test.DejaFu.SCT

Way is now a GADT, no longer taking a type parameter. This greatly improves type inference when the Systematically constructor is used.
- The NFData instance for Way is now gone. The alternative was requiring that any RandomGen used also implement NFData, which is very restrictive

Miscellaneous

There is now a changelog.
Test.DejaFu.Common is now considered to form part of the public API of the library.
Every definition and instance now has a Haddock "@since" annotation.

0.5.1.3

Date 2017-04-05
Git tag dejafu-0.5.1.3
Hackage https://hackage.haskell.org/package/dejafu-0.5.1.3

Miscellaneous

The version range on the concurrency package has been changed to 1.1.*.

0.5.1.2

Date 2017-03-04
Git tag dejafu-0.5.1.2
Hackage https://hackage.haskell.org/package/dejafu-0.5.1.2

This version was misnumbered! It should have caused a minor version bump!

Test.DejaFu.Conc

New MonadRef and MonadAtomicRef instances for the Conc type using CRef.

Fixed

A long-standing bug where if the main thread is killed with a throwTo, the throwing neither appears in the trace nor correctly terminates the execution.

Miscellaneous

The maximum supported version of the concurrency package has been changed to 1.1.1.*.

0.5.1.1

Date 2017-02-25
Git tag dejafu-0.5.1.1
Hackage https://hackage.haskell.org/package/dejafu-0.5.1.1

Fixed

The correct scheduler state is now passed to the scheduler immediately after the termination of a subconcurrency action.
SCT of subconcurrency no longer loops infinitely.

0.5.1.0

Date 2017-02-25
Git tag dejafu-0.5.1.0
Hackage https://hackage.haskell.org/package/dejafu-0.5.1.0

Test.DejaFu

A new NFData instance for Result.

Test.DejaFu.Common

New instances:
- NFData for ThreadId, CRefId, MVarId, TVarId, IdSource, ThreadAction, Lookahead, ActionType, TAction, Decision, Failure, and MemType.
- Eq, Ord, and Show instances for IdSource.

Test.DejaFu.SCT

New NFData instances for Way, Bounds, PreemptionBound, FairBound, and LengthBound.
New strict variants of runSCT and resultsSet: runSCT' and resultsSet'.

Test.DejaFu.STM

A new NFData instance for Result.

0.5.0.2

Date 2017-02-22
Git tag dejafu-0.5.0.2
Hackage https://hackage.haskell.org/package/dejafu-0.5.0.2

This version was misnumbered! It should have caused a major version bump!

Test.DejaFu.Common

A new StopSubconcurrency constructor of ThreadAction.

Changed

A StopConcurrency action appears in the execution trace immediately after the end of a subconcurrency action (much like the PopCatching and ResetMasking actions which appear after a catch and mask).
A subconcurrency action now inherits the number of capabilities from the outer computation, rather than being reset to 2 as before.

Miscellaneous

Test.DejaFu.SCT now compiles with MonoLocalBinds enabled (implied by GADTs and TypeFamilies), which may be relevant to hackers.

0.5.0.1

Date 2017-02-21
Git tag dejafu-0.5.0.1
This version was never pushed to hackage, whoops!

Fixed

readMVar is once again considered a "release action" for the purposes of fair-bounding.

0.5.0.0

Date 2017-02-21
Git tag dejafu-0.5.0.0
Hackage https://hackage.haskell.org/package/dejafu-0.5.0.0

Test.DejaFu

All the functions which did take a Bounds now take a Way instead and support random scheduling as well.

Test.DejaFu.Common

New Eq instances for ThreadAction and Lookahead.
A TryReadMVar constructor for ThreadAction and a corresponding WillTryReadMVar constructor for Lookahead.

Test.DejaFu.Conc

A new testing-only subconcurrency function, to run a concurrent action and do something with its result in the same concurrent context, even if it fails.

Test.DejaFu.SCT

An sctRandom function to run a fixed number of randomly-scheduled executions of a program.
The Way type, to abstract over how to run a concurrent program, used by new functions runSCT and resultsSet.

Fixed

Some previously-missed CRef action dependencies are no longer missed.

Miscellaneous

The supported version of the concurrency package was bumped to 1.1.0.0, introducing tryReadMVar.
A bunch of things were called "Var" or "Ref", these are now consistently "MVar" and "CRef".
Significant performance improvements in both time and space.
The dpor package has been merged back into this, as it turned out not to be very generally useful. There is no direct replacement, but I have no intent to update it, so the dpor package is now deprecated.

0.4.0.0

Date 2016-09-10
Git tag dejafu-0.4.0.0
Hackage https://hackage.haskell.org/package/dejafu-0.4.0.0

Test.DejaFu

The autocheck' function now takes the schedule bounds as a parameter.
New runTestM and runTestM' functions, monad-polymorphic variants of the now-removed runTestIO and runTestIO' functions.

Test.DejaFu.Conc

The Conc type no longer has the STM type as a parameter.
A new runConcurrent function, a monad-polymorphic version of the now-removed runConcST and runConcIO functions.

Test.DejaFu.SCT

The ST-specific functions are now monad-polymorphic.
The IO function variants have been removed.

Test.DejaFu.STM

A new runTransaction function, a monad-polymorphic version of the now-removed runTransactionST and runTransactionIO functions.

Changed

The termination of the main thread in execution traces now appears as a single Stop, rather than the sequence Lift, Stop.
Execution traces printed by the helpful functions in Test.DejaFu now include a key of thread names.

Miscellaneous

Remodularisation:
- The Control.* modules have all been split out into a separate "concurrency" package.
- Many definitions from other modules have been moved to the new Test.DejaFu.Common module.
- The Test.DejaFu.Deterministic module has been renamed to Test.DejaFu.Conc

0.3.2.1

Date 2016-07-21
Git tag dejafu-0.3.2.1
Hackage https://hackage.haskell.org/package/dejafu-0.3.2.1

Fixed

The implementation of the STM orElse for STMLike incorrectly handled some state non-associatively, leading to false deadlocks being reported in some cases.

0.3.2.0

Date 2016-06-06
Git tag dejafu-0.3.2.0
Hackage https://hackage.haskell.org/package/dejafu-0.3.2.0

Builds with both dpor-0.1 and dpor-0.2, however some improvements require dpor-0.2.

Fixed

(faster with dpor-0.2) Executions missed due to daemon threads with uninteresting first actions are no longer missed.

Changed

(requires dpor-0.2) Significantly improved dependency inference of exceptions, greatly improving performance of testcases using exceptions.
Significantly improved dependency inference of STM transactions, greatly improving performance of testcases using STM.

0.3.1.1

Date 2016-05-26
Git tag dejafu-0.3.1.1
Hackage https://hackage.haskell.org/package/dejafu-0.3.1.1

Miscellaneous

Now supports GHC 8.

0.3.1.0

Date 2016-05-02
Git tag dejafu-0.3.1.0
Hackage https://hackage.haskell.org/package/dejafu-0.3.1.0

Fixed

Context switches around relaxed memory commit actions could cause the number of pre-emptions in an execution to be miscounted, leading to the pre-emption bounding being too lenient.

0.3.0.0

Date 2016-04-03
Git tag dejafu-0.3.0.0
Hackage https://hackage.haskell.org/package/dejafu-0.3.0.0

The minimum supported version of GHC is now 7.10.

I didn't write proper release notes, and this is so far back I don't really care to dig through the logs.

0.2.0.0

Date 2015-12-01
Git tag 0.2.0.0
Hackage https://hackage.haskell.org/package/dejafu-0.2.0.0

I didn't write proper release notes, and this is so far back I don't really care to dig through the logs.

0.1.0.0

Date 2015-08-27
Git tag 0.1.0.0
Hackage https://hackage.haskell.org/package/dejafu-0.1.0.0

Initial release. Go read the API docs.