barrucadu/dejafu
1
1
Fork 0
mirror of https://github.com/barrucadu/dejafu.git synced 2024-11-22 03:52:12 +03:00
Code Issues Projects Releases Wiki Activity

Redirect old readthedocs site

Browse Source 
I've also added redirects for old links - those are configured in the
admin panel, rather than in code.
This commit is contained in:
Michael Walker 2023-10-19 20:12:30 +01:00
parent a4d31bdaaa
commit 83e391847f
No known key found for this signature in database
22 changed files with 55 additions and 1591 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
.readthedocs.yaml Normal file
View File

@ -0,0 +1,13 @@
version: "2"
build:
os: "ubuntu-22.04"
tools:
python: "3.10"
python:
install:
- requirements: docs/readthedocs/requirements.txt
sphinx:
configuration: docs/readthedocs/source/conf.py

1
doc/.gitignore vendored
View File

@ -1 +0,0 @@
_build

102
doc/advanced.rst
View File

@ -1,102 +0,0 @@
Advanced Usage
==============
Déjà Fu tries to have a sensible set of defaults, but there are some
times when the defaults are not suitable. There are a lot of knobs
provided to tweak how things work.
.. _settings:
Execution settings
------------------
The ``autocheckWithSettings``, ``dejafuWithSettings``, and
``dejafusWithSettings`` let you provide a ``Settings`` value, which
controls some of Déjà Fu's behaviour:
.. code-block:: haskell
dejafuWithSettings mySettings "Assert the thing holds" myPredicate myAction
The available settings are:
* **"Way"**, how to explore the behaviours of the program under test.
* **Length bound**, a cut-off point to terminate an execution even if
it's not done yet.
* **Memory model**, which affects how non-synchronised operations,
such as ``readIORef`` and ``writeIORef`` behave.
* **Discarding**, which allows throwing away uninteresting results,
rather than keeping them around in memory.
* **Early exit**, which allows exiting as soon as a result matching a
predicate is found.
* **Representative traces**, keeping only one execution trace for each
distinct result.
* **Trace simplification**, rewriting execution traces into a simpler
form (particularly effective with the random testing).
* **Safe IO**, pruning needless schedules when your IO is only used to
manage thread-local state.
See the ``Test.DejaFu.Settings`` module for more information.
.. _performance:
Performance tuning
------------------
* Are you happy to trade space for time?
Consider computing the results once and running multiple
predicates over the output: this is what ``dejafus`` /
``testDejafus`` / etc does.
* Can you sacrifice completeness?
Consider using the random testing functionality. See the ``*WithSettings``
functions.
* Would strictness help?
Consider using the strict functions in ``Test.DejaFu.SCT`` (the
ones ending with a ``'``).
* Do you just want the set of results, and don't care about traces?
Consider using ``Test.DejaFu.SCT.resultsSet``.
* Do you know something about the sort of results you care about?
Consider discarding results you *don't* care about. See the
``*WithSettings`` functions in ``Test.DejaFu``, ``Test.DejaFu.SCT``,
and ``Test.{HUnit,Tasty}.DejaFu``.
For example, let's say you want to know if your test case deadlocks,
but you don't care about the execution trace, and you are going to
sacrifice completeness because your possible state-space is huge. You
could do it like this:
.. code-block:: haskell
dejafuWithSettings
( set ldiscard
-- "efa" == "either failure a", discard everything but deadlocks
(Just $ \efa -> Just (if either isDeadlock (const False) efa then DiscardTrace else DiscardResultAndTrace))
. set lway
-- try 10000 executions with random scheduling
(randomly (mkStdGen 42) 10000)
$ defaultSettings
)
-- the name of the test
"Never Deadlocks"
-- the predicate to check
deadlocksNever
-- your test case
testCase

1
doc/changelog_concurrency.rst
View File

@ -1 +0,0 @@
../concurrency/CHANGELOG.rst

1
doc/changelog_dejafu.rst
View File

@ -1 +0,0 @@
../dejafu/CHANGELOG.rst

1
doc/changelog_hunit-dejafu.rst
View File

@ -1 +0,0 @@
../hunit-dejafu/CHANGELOG.rst

1
doc/changelog_tasty-dejafu.rst
View File

@ -1 +0,0 @@
../tasty-dejafu/CHANGELOG.rst

171
doc/conf.py
View File

@ -1,171 +0,0 @@
# -*- coding: utf-8 -*-
#
# Déjà Fu documentation build configuration file, created by
# sphinx-quickstart on Tue Aug 15 19:55:19 2017.
#
# This file is execfile()d with the current directory set to its
# containing dir.
#
# Note that not all possible configuration values are present in this
# autogenerated file.
#
# All configuration values have a default; values that are commented out
# serve to show the default.
# If extensions (or modules to document with autodoc) are in another directory,
# add these directories to sys.path here. If the directory is relative to the
# documentation root, use os.path.abspath to make it absolute, like shown here.
#
# import os
# import sys
# sys.path.insert(0, os.path.abspath('.'))
import os
# -- General configuration ------------------------------------------------
# If your documentation needs a minimal Sphinx version, state it here.
#
# needs_sphinx = '1.0'
# Add any Sphinx extension module names here, as strings. They can be
# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
# ones.
extensions = ['sphinx.ext.extlinks']
# Add any paths that contain templates here, relative to this directory.
templates_path = ['_templates']
# The suffix(es) of source filenames.
# You can specify multiple suffix as a list of string:
source_parsers = {
}
source_suffix = ['.rst']
# The master toctree document.
master_doc = 'index'
# General information about the project.
project = u'Déjà Fu'
copyright = u'2017--2018, Michael Walker'
author = u'Michael Walker'
# External link destinations
_repo = 'https://github.com/barrucadu/dejafu/'
extlinks = {
'commit': (_repo + 'commit/%s', 'commit '),
'issue': (_repo + 'issues/%s', 'issue #'),
'pull': (_repo + 'pull/%s', 'pull request #'),
'tag': (_repo + 'releases/tag/%s', 'tag '),
'github': (_repo + '%s', ''),
'u': ('https://github.com/%s', ''),
'hackage': ('https://hackage.haskell.org/package/%s', ''),
'stackage': ('https://www.stackage.org/package/%s', ''),
}
# The version info for the project you're documenting, acts as replacement for
# |version| and |release|, also used in various other places throughout the
# built documents.
#
# The short X.Y version.
version = u'HEAD'
# The full version, including alpha/beta/rc tags.
release = u'HEAD'
# The language for content autogenerated by Sphinx. Refer to documentation
# for a list of supported languages.
#
# This is also used if you do content translation via gettext catalogs.
# Usually you set "language" from the command line for these cases.
language = None
# List of patterns, relative to source directory, that match files and
# directories to ignore when looking for source files.
# This patterns also effect to html_static_path and html_extra_path
exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store']
# The name of the Pygments (syntax highlighting) style to use.
pygments_style = 'sphinx'
# If true, `todo` and `todoList` produce output, else they produce nothing.
todo_include_todos = False
# -- Options for HTML output ----------------------------------------------
# The theme to use for HTML and HTML Help pages. See the documentation for
# a list of builtin themes.
#
html_theme = os.environ['SPHINX_THEME'] if 'SPHINX_THEME' in os.environ else 'default'
# Theme options are theme-specific and customize the look and feel of a theme
# further. For a list of options available for each theme, see the
# documentation.
#
# html_theme_options = {}
# Add any paths that contain custom static files (such as style sheets) here,
# relative to this directory. They are copied after the builtin static files,
# so a file named "default.css" will overwrite the builtin "default.css".
html_static_path = ['_static']
# -- Options for HTMLHelp output ------------------------------------------
# Output file base name for HTML help builder.
htmlhelp_basename = 'DejaFudoc'
# -- Options for LaTeX output ---------------------------------------------
latex_elements = {
# The paper size ('letterpaper' or 'a4paper').
#
# 'papersize': 'letterpaper',
# The font size ('10pt', '11pt' or '12pt').
#
# 'pointsize': '10pt',
# Additional stuff for the LaTeX preamble.
#
# 'preamble': '',
# Latex figure (float) alignment
#
# 'figure_align': 'htbp',
}
# Grouping the document tree into LaTeX files. List of tuples
# (source start file, target name, title,
# author, documentclass [howto, manual, or own class]).
latex_documents = [
(master_doc, 'DejaFu.tex', u'Déjà Fu Documentation',
u'Michael Walker', 'manual'),
]
# -- Options for manual page output ---------------------------------------
# One entry per manual page. List of tuples
# (source start file, name, description, authors, manual section).
man_pages = [
(master_doc, 'dejafu', u'Déjà Fu Documentation',
[author], 1)
]
# -- Options for Texinfo output -------------------------------------------
# Grouping the document tree into Texinfo files. List of tuples
# (source start file, target name, title, author,
# dir menu entry, description, category)
texinfo_documents = [
(master_doc, 'DejaFu', u'Déjà Fu Documentation',
author, 'DejaFu', 'Concurrency testing for Haskell.',
'Miscellaneous'),
]

219
doc/contributing.rst
View File

@ -1,219 +0,0 @@
Contributing
============
Thanks for caring about Déjà Fu!
Ways to contribute
------------------
Déjà Fu is a project under active development, there's always
something to do. Here's a list of ideas to get you started:
* Submit bug reports.
* Submit feature requests.
* Got a particularly slow test case which you think should be faster?
Open an issue for that too.
* Blog about how and why you use Déjà Fu.
* Check if any bugs which have been open for a while are still bugs.
If you want to contribute code, you could:
* Tackle one of the issues tagged :github:`"good first issue" <labels/good%20first%20issue>`.
* Tackle a bigger issue, perhaps one of the :github:`roadmap issues <labels/roadmap>`!
* Run code coverage and try to fix a gap in the tests.
* Profile the test suite and try to improve a slow function.
:github:`Roadmap issues <labels/roadmap>` are priority issues (in my
opinion), so help with those is especially appreciated.
If you have a support question, you can talk to me on IRC (#haskell on
freenode) or send an email (mike@barrucadu.co.uk) rather than opening
an issue. But maybe your question is a bug report about poor
documentation in disguise!
Making the change
-----------------
1. Talk to me!
I don't bite, and chances are I can quickly tell you where you
should start. It's better to ask what seems like a stupid question
than to waste a lot of time on the wrong approach.
2. Make the change.
Figure out what needs to be changed, how to change it, and do it.
If you're fixing a bug, make sure to add a minimal reproduction to
Cases.Regressions in dejafu-tests.
3. Document the change.
All top-level definitions should have a `Haddock`__ comment
explaining what it does. If you've added or changed a top-level
function, consider commenting its arguments too.
If you've added a top-level definition, or changed one in a
backwards-incompatible way, add an ``@since unreleased`` Haddock
comment to it. This is to help prevent me from missing things when
I update the changelog ahead of a release.
4. Submit a PR.
GitHub Actions will run some checks, which might prompt further
action. You should expect a response from me in a day or two.
Don't worry about your PR being perfect the first time. We'll work
through any issues together, to ensure that Déjà Fu gets the best code
it can.
.. __: https://github.com/aisamanra/haddock-cheatsheet
Coding style
------------
There isn't really a prescribed style. It's not quite the wild west
though; keep these three rules in mind:
1. Be consistent.
2. Run :hackage:`stylish-haskell` to format import lists.
3. Use :hackage:`hlint` and :hackage:`weeder` and fix lints unless you
have a good reason not to.
GitHub Actions runs stylish-haskell and hlint on all PRs.
Coverage
--------
`hpc`__ can generate a coverage report from the execution of
dejafu-tests:
.. code-block:: none
$ stack build --coverage
$ stack exec dejafu-tests
$ stack hpc report --all dejafu-tests.tix
This will print some stats and generate an HTML coverage report:
.. code-block:: none
Generating combined report
52% expressions used (4052/7693)
48% boolean coverage (63/129)
43% guards (46/106), 31 always True, 9 always False, 20 unevaluated
68% 'if' conditions (11/16), 2 always True, 3 unevaluated
85% qualifiers (6/7), 1 unevaluated
61% alternatives used (392/635)
80% local declarations used (210/261)
26% top-level declarations used (280/1063)
The combined report is available at /home/barrucadu/projects/dejafu/.stack-work/install/x86_64-linux/nightly-2016-06-20/8.0.1/hpc/combined/custom/hpc_index.html
The highlighted code in the HTML report emphasises branch coverage:
* Red means a branch was evaluated as always false.
* Green means a branch was evaluated as always true.
* Yellow means an expression was never evaluated.
See also the `stack coverage documentation`__.
.. __: https://wiki.haskell.org/Haskell_program_coverage
.. __: https://docs.haskellstack.org/en/latest/coverage/
Performance
-----------
GHC can generate performance statistics from the execution of
dejafu-tests:
.. code-block:: none
$ stack build --profile
$ stack exec -- dejafu-tests +RTS -p
$ less dejafu-tests.prof
This prints a detailed breakdown of where memory and time are being
spent:
.. code-block:: none
Mon Mar 20 19:26 2017 Time and Allocation Profiling Report (Final)
dejafu-tests +RTS -p -RTS
total time = 105.94 secs (105938 ticks @ 1000 us, 1 processor)
total alloc = 46,641,766,952 bytes (excludes profiling overheads)
COST CENTRE MODULE %time %alloc
findBacktrackSteps.doBacktrack.idxs' Test.DejaFu.SCT.Internal 21.9 12.0
== Test.DejaFu.Common 12.4 0.0
yieldCount.go Test.DejaFu.SCT 12.1 0.0
dependent' Test.DejaFu.SCT 5.1 0.0
runThreads.go Test.DejaFu.Conc.Internal 2.7 4.1
[...]
Be careful, however! Compiling with profiling can significantly
affect the behaviour of a program! Use profiling to get an idea of
where the hot spots are, but make sure to confirm with a non-profiled
build that things are actually getting faster.
If you compile with ``-rtsopts`` you can get some basic stats from a
non-profiled build:
.. code-block:: none
$ stack exec -- dejafu-tests +RTS -s
[...]
86,659,658,504 bytes allocated in the heap
13,057,037,448 bytes copied during GC
13,346,952 bytes maximum residency (4743 sample(s))
127,824 bytes maximum slop
37 MB total memory in use (0 MB lost due to fragmentation)
Tot time (elapsed) Avg pause Max pause
Gen 0 78860 colls, 0 par 32.659s 32.970s 0.0004s 0.0669s
Gen 1 4743 colls, 0 par 3.043s 3.052s 0.0006s 0.0086s
TASKS: 174069 (174065 bound, 4 peak workers (4 total), using -N1)
SPARKS: 0 (0 converted, 0 overflowed, 0 dud, 0 GC'd, 0 fizzled)
INIT time 0.001s ( 0.001s elapsed)
MUT time 98.685s (101.611s elapsed)
GC time 35.702s ( 36.022s elapsed)
EXIT time 0.001s ( 0.007s elapsed)
Total time 134.388s (137.640s elapsed)
Alloc rate 878,145,635 bytes per MUT second
Productivity 73.4% of total user, 73.8% of total elapsed
Heap profiling
--------------
GHC can tell you where the memory is going:
.. code-block:: none
$ stack build --profile
$ stack exec -- dejafu-tests +RTS -hc
$ hp2ps -c dejafu-tests.hp
This will produce a graph of memory usage over time, as a postscript
file, broken down by cost-centre which produced the data. There are a
few different views:
- ``-hm`` breaks down the graph by module
- ``-hd`` breaks down the graph by closure description
- ``-hy`` breaks down the graph by type
I typically find ``-hd`` and ``-hy`` most useful. If you're feeling
particularly brave, you can try ``-hr``, which is intended to help
track down memory leaks caused by unevaluated thunks.

161
doc/getting_started.rst
View File

@ -1,161 +0,0 @@
Getting Started
===============
[Déjà Fu is] A martial art in which the user's limbs move in time
as well as space, […] It is best described as "the feeling that
you have been kicked in the head this way before"
**Terry Pratchett, Thief of Time**
Déjà Fu is a unit-testing library for concurrent Haskell programs.
Tests are deterministic and expressive, making it easy and convenient
to test your threaded code. Available on :github:`GitHub <>`,
:hackage:`Hackage <dejafu>`, and :stackage:`Stackage <dejafu>`.
Features:
* An abstraction over the concurrency functionality in ``IO``
* Deterministic testing of nondeterministic code
* Both complete (slower) and incomplete (faster) modes
* A unit-testing-like approach to writing test cases
* A property-testing-like approach to comparing stateful operations
* Testing of potentially nonterminating programs
* Integration with :hackage:`HUnit` and :hackage:`tasty`
There are a few different packages under the Déjà Fu umbrella:
.. csv-table::
:header: "Package", "Version", "Summary"
":hackage:`concurrency`", "1.11.0.3", "Typeclasses, functions, and data types for concurrency and STM"
":hackage:`dejafu`", "2.4.0.5", "Systematic testing for Haskell concurrency"
":hackage:`hunit-dejafu`", "2.0.0.6", "Déjà Fu support for the HUnit test framework"
":hackage:`tasty-dejafu`", "2.1.0.1", "Déjà Fu support for the tasty test framework"
Installation
------------
Install from Hackage globally:
.. code-block:: none
$ cabal install dejafu
Or add it to your cabal file:
.. code-block:: none
build-depends: ...
, dejafu
Or to your package.yaml:
.. code-block:: none
dependencies:
...
- dejafu
Quick start guide
-----------------
Déjà Fu supports unit testing, and comes with a helper function
called ``autocheck`` to look for some common issues. Let's see it in
action:
.. code-block:: haskell
import Control.Concurrent.Classy
myFunction :: MonadConc m => m String
myFunction = do
var <- newEmptyMVar
fork (putMVar var "hello")
fork (putMVar var "world")
readMVar var
That ``MonadConc`` is a typeclass abstraction over concurrency, but
we'll get onto that shortly. First, the result of testing:
.. code-block:: none
> autocheck myFunction
[pass] Successful
[fail] Deterministic
"hello" S0----S1--S0--
"world" S0----S2--S0--
False
There are no concurrency errors, which is good; but the program is (as
you probably spotted) nondeterministic!
Along with each result, Déjà Fu gives us a representative execution
trace in an abbreviated form. ``Sn`` means that thread ``n`` started
executing, and ``Pn`` means that thread ``n`` pre-empted the
previously running thread.
Why Déjà Fu?
------------
Testing concurrent programs is difficult, because in general they are
nondeterministic. This leads to people using work-arounds like
running their testsuite many thousands of times; or running their
testsuite while putting their machine under heavy load.
These approaches are inadequate for a few reasons:
* **How many runs is enough?** When you are just hopping to spot a bug
by coincidence, how do you know to stop?
* **How do you know if you've fixed a bug you saw previously?**
Because the scheduler is a black box, you don't know if the
previously buggy schedule has been re-run.
* **You won't actually get that much scheduling variety!** Operating
systems and language runtimes like to run threads for long periods
of time, which reduces the variety you get (and so drives up the
number of runs you need).
Déjà Fu addresses these points by offering *complete* testing. You
can run a test case and be guaranteed to find all results with some
bounds. These bounds can be configured, or even disabled! The
underlying approach used is smarter than merely trying all possible
executions, and will in general explore the state-space quickly.
If your test case is just too big for complete testing, there is also
a random scheduling mode, which is necessarily *incomplete*. However,
Déjà Fu will tend to produce much more scheduling variety than just
running your test case in ``IO`` a bunch of times, and so bugs will
tend to crop up sooner. Furthermore, as you get execution traces out,
you can be certain that a bug has been fixed by following the trace by
eye.
**If you'd like to get involved with Déjà Fu**, check out :github:`the
"good first issue" label on the issue tracker
<issues?q=is%3Aissue+is%3Aopen+label%3A%22good+first+issue%22>`.
Questions, feedback, discussion
-------------------------------
* For general help talk to me in IRC (barrucadu in #haskell) or shoot
me an email (mike@barrucadu.co.uk)
* For bugs, issues, or requests, please :issue:`file an issue <>`.
Bibliography
------------
Déjà Fu has been produced as part of my Ph.D work, and wouldn't be
possible without prior research. Here are the core papers:
* Bounded partial-order reduction, K. Coons, M. Musuvathi,
and K. McKinley (2013)
* Dynamic Partial Order Reduction for Relaxed Memory
Models, N. Zhang, M. Kusano, and C. Wang (2015)
* Concurrency Testing Using Schedule Bounding: an Empirical
Study, P. Thompson, A. Donaldson, and A. Betts (2014)
* On the Verification of Programs on Relaxed Memory
Models, A. Linden (2014)

70
doc/ghc.rst
View File

@ -1,70 +0,0 @@
Supported GHC Versions
======================
Déjà Fu supports the latest four GHC releases, at least. For testing
purposes, we use Stackage snapshots as a proxy for GHC versions. The
currently supported versions are:
.. csv-table::
:header: "GHC", "Stackage", "base"
"9.6", "Nightly 2021-07-01", "4.18.0.0"
"9.4", "LTS 21.0", "4.17.0.0"
"9.2", "LTS 20.0", "4.16.0.0"
"9.0", "LTS 19.0", "4.15.0.0"
"8.10", "LTS 17.0", "4.14.1.0"
"8.8", "LTS 15.0", "4.13.0.0"
"8.6", "LTS 14.0", "4.12.0.0"
"8.4", "LTS 12.0", "4.11.0.0"
"8.2", "LTS 10.0", "4.10.1.0"
In practice, we may *compile with* older versions of GHC, but keeping
them working is not a priority.
Adding new GHC releases
-----------------------
When a new version of GHC is released, we need to make some changes
for everything to go smoothly. In general, these changes should only
cause a **patch level version bump**.
1. Bump the upper bound of :hackage:`base` and set up any needed
conditional compilation
2. Add the GHC and base versions to the table.
3. Remove any unsupported versions from the table.
4. Make a patch release.
A new GHC release won't get a Stackage snapshot for little while. When it
does:
1. Add the snapshot to the GitHub Actions configuration.
2. Update the resolver in the stack.yaml.
3. Put the snapshot in the table.
Dropping old GHC releases
-------------------------
When we want to drop an unsupported version of GHC, we need to bump
the version bound on :hackage:`base` to preclude it. This is a
backwards-incompatible change which causes a **major version bump**.
1. Remove the dropped GHC version from the GitHub Actions
configuration.
2. Bump the lower bound of :hackage:`base`.
3. Look through the other dependencies. Some may not work with our
new lower bound on :hackage:`base`, so we should bump those too.
4. Remove any now-irrelevant conditional compilation (mostly CPP, but
there may also be some cabal file bits).
5. Make whatever change required the bump.
6. Make a major release.
GHC versions shouldn't be dropped just because we can, but here are
some good reasons to do it:
* We want to bump the lower bounds of a dependency to a version which
doesn't support that GHC.
* We want to add a new dependency which doesn't support that GHC.
* The conditional compilation needed to keep that GHC working is
getting confusing.

42
doc/index.rst
View File

@ -1,42 +0,0 @@
This is Déjà Fu
===============
[Déjà Fu is] A martial art in which the user's limbs move in time
as well as space, […] It is best described as "the feeling that
you have been kicked in the head this way before"
**Terry Pratchett, Thief of Time**
.. toctree::
:maxdepth: 2
:caption: User Documentation
getting_started
typeclass
unit_testing
refinement_testing
advanced
.. toctree::
:maxdepth: 2
:caption: Migration Guides
migration_1x_2x
migration_0x_1x
.. toctree::
:maxdepth: 2
:caption: Developer Documentation
contributing
ghc
release_process
.. toctree::
:maxdepth: 2
:caption: Release Notes
concurrency <changelog_concurrency>
dejafu <changelog_dejafu>
hunit-dejafu <changelog_hunit-dejafu>
tasty-dejafu <changelog_tasty-dejafu>

117
doc/migration_0x_1x.rst
View File

@ -1,117 +0,0 @@
0.x to 1.x
==========
:hackage:`dejafu-1.0.0.0` is a super-major release which breaks
compatibility with :hackage:`dejafu-0.x <dejafu-0.9.1.1>` quite
significantly, but brings with it support for bound threads, and
significantly improves memory usage in the general case.
Highlights reel:
* Most predicates now only need to keep around the failures, rather
than all results.
* Support for bound threads (with :hackage:`concurrency-1.3.0.0`).
* The ``ST`` / ``IO`` interface duplication is gone, everything is now
monadic.
* Function parameter order is closer to other testing libraries.
* Much improved API documentation.
See the changelogs for the full details.
``ST`` and ``IO`` functions
---------------------------
There is only one set of functions now. Testing bound threads
requires being able to fork actual threads, so testing with ``ST`` is
no longer possible. The ``ConcST`` type is gone, there is only
``ConcIO``.
For :hackage:`dejafu` change:
* ``autocheckIO`` to ``autocheck``
* ``dejafuIO`` to ``dejafu``
* ``dejafusIO`` to ``dejafus``
* ``autocheckWayIO`` to ``autocheckWay``
* ``dejafuWayIO`` to ``dejafuWay``
* ``dejafusWayIO`` to ``dejafusWay``
* ``dejafuDiscardIO`` to ``dejafuDiscard``
* ``runTestM`` to ``runTest``
* ``runTestWayM`` to ``runTestWay``
If you relied on being able to get a pure result from the ``ConcST``
functions, you can no longer do this.
For :hackage:`hunit-dejafu` and :hackage:`tasty-dejafu` change:
* ``testAutoIO`` to ``testAuto``
* ``testDejafuIO`` to ``testDejafu``
* ``testDejafusIO`` to ``testDejafus``
* ``testAutoWayIO`` to ``testAutoWay``
* ``testDejafuWayIO`` to ``testDejafuWay``
* ``testDejafusWayIO`` to ``testDejafusWay``
* ``testDejafuDiscardIO`` to ``testDejafuDiscard``
Function parameter order
------------------------
Like :hackage:`HUnit`, the monadic action to test is now the last
parameter of the testing functions. This makes it convenient to write
tests without needing to define the action elsewhere.
For :hackage:`dejafu` change:
* ``dejafu ma (s, p)`` to ``dejafu s p ma``
* ``dejafus ma ps`` to ``dejafus ps ma``
* ``dejafuWay way mem ma (s, p)`` to ``dejafuWay way mem s p ma``
* ``dejafusWay way mem ma ps`` to ``dejafuWay way mem ps ma``
* ``dejafuDiscard d way mem ma (s, p)`` to ``dejafuDiscard d way mem s p ma``
For :hackage:`hunit-dejafu` and :hackage:`tasty-dejafu` change:
* ``testDejafu ma s p`` to ``testDejafu s p ma``
* ``testDejafus ma ps`` to ``testDejafus ps ma``
* ``testDejafuWay way mem ma s p`` to ``testDejafuWay way mem s p ma``
* ``testDejafusWay way mem ma ps`` to ``testDejafusWay way mem ps ma``
* ``testDejafuDiscard d way mem ma s p`` to ``testDejafuDiscard d way mem s p ma``
Predicates
----------
The ``Predicate a`` type is now an alias for ``ProPredicate a a``,
defined like so:
.. code-block:: haskell
data ProPredicate a b = ProPredicate
{ pdiscard :: Either Failure a -> Maybe Discard
-- ^ Selectively discard results before computing the result.
, peval :: [(Either Failure a, Trace)] -> Result b
-- ^ Compute the result with the un-discarded results.
}
If you use the predicate helper functions to construct a predicate,
you do not need to change anything (and should get a nice reduction in
your resident memory usage). If you supply a function directly, you
can recover the old behaviour like so:
.. code-block:: haskell
old :: ([(Either Failure a, Trace)] -> Result a) -> ProPredicate a a
old p = ProPredicate
{ pdiscard = const Nothing
, peval = p
}
The ``alwaysTrue2`` helper function is gone. If you use it, use
``alwaysSameOn`` or ``alwaysSameBy`` instead.
Need help?
----------
* For general help talk to me in IRC (barrucadu in #haskell) or shoot
me an email (mike@barrucadu.co.uk)
* For bugs, issues, or requests, please :issue:`file an issue <>`.

116
doc/migration_1x_2x.rst
View File

@ -1,116 +0,0 @@
1.x to 2.x
==========
:hackage:`dejafu-2.0.0.0` is a super-major release which breaks
compatibility with :hackage:`dejafu-1.x <dejafu-1.12.0.0>`.
Highlights reel:
* Test cases are written in terms of a new ``Program`` type.
* The ``Failure`` type has been replaced with a ``Condition`` type
(actually in 1.12).
* Random testing takes an optional length bound.
* Atomically-checked invariants over shared mutable state.
See the changelogs for the full details.
The ``Program`` type
--------------------
The ``ConcT`` type is now an alias for ``Program Basic``.
A ``Program Basic`` has all the instances ``ConcT`` did, defined using
the ``~`` instance trick, so this shouldn't be a breaking change:
.. code-block:: haskell
instance (pty ~ Basic) => MonadTrans (Program pty)
instance (pty ~ Basic) => MonadCatch (Program pty n)
instance (pty ~ Basic) => MonadThrow (Program pty n)
instance (pty ~ Basic) => MonadMask (Program pty n)
instance (pty ~ Basic, Monad n) => MonadConc (Program pty n)
instance (pty ~ Basic, MonadIO n) => MonadIO (Program pty n)
The ``dontCheck`` function has been removed in favour of
``withSetup``:
.. code-block:: haskell
do x <- dontCheck setup
action x
-- becomes
withSetup setup action
The ``subconcurrency`` function has been removed in favour of
``withSetupAndTeardown``:
.. code-block:: haskell
do x <- setup
y <- subconcurrency (action x)
teardown x y
-- becomes
withSetupAndTeardown setup teardown action
The ``dontCheck`` and ``subconcurrency`` functions used to throw
runtime errors if nested. This is not possible with ``withSetup`` and
``withSetupAndTeardown`` due to their types:
.. code-block:: haskell
withSetup
:: Program Basic n x
-- ^ Setup action
-> (x -> Program Basic n a)
-- ^ Main program
-> Program (WithSetup x) n a
withSetupAndTeardown
:: Program Basic n x
-- ^ Setup action
-> (x -> Either Condition y -> Program Basic n a)
-- ^ Teardown action
-> (x -> Program Basic n y)
-- ^ Main program
-> Program (WithSetupAndTeardown x y) n a
Previously, multiple calls to ``subconcurrency`` could be sequenced in
the same test case. This is not possible using
``withSetupAndTeardown``. If you rely on this behaviour, please
:issue:`file an issue <>`.
The ``Condition`` type
----------------------
This is a change in :hackage:`dejafu-1.12.0.0`, but the alias
``Failure = Condition`` is removed in :hackage:`dejafu-2.0.0.0`.
* The ``STMDeadlock`` and ``Deadlock`` constructors have been merged.
* Internal errors have been split into the ``Error`` type and are
raised as exceptions, instead of being returned as conditions.
The name "failure" has been a recurring source of confusion, because
an individual execution can "fail" without the predicate as a whole
failing. My hope is that the more neutral "condition" will prevent
this confusion.
Deprecated functions
--------------------
All the deprecated special-purpose functions have been removed. Use
more general ``*WithSettings`` functions instead.
Need help?
----------
* For general help talk to me in IRC (barrucadu in #haskell) or shoot
me an email (mike@barrucadu.co.uk)
* For bugs, issues, or requests, please :issue:`file an issue <>`.

152
doc/refinement_testing.rst
View File

@ -1,152 +0,0 @@
Refinement Testing
==================
Déjà Fu also supports a form of property-testing where you can check
things about the side-effects of stateful operations. For example, we
can assert that ``readMVar`` is equivalent to sequencing ``takeMVar``
and ``putMVar`` like so:
.. code-block:: haskell
prop_mvar_read_take_put =
sig readMVar `equivalentTo` sig (\v -> takeMVar v >>= putMVar v)
Given the signature function, ``sig``, defined in the next section.
If we check this, our property fails!
.. code-block:: none
> check prop_mvar_read_take_put
*** Failure: (seed Just 0)
left: [(Nothing,Just 0)]
right: [(Nothing,Just 0),(Just Deadlock,Just 0)]
False
This is because ``readMVar`` is atomic, whereas sequencing
``takeMVar`` with ``putMVar`` is not, and so another thread can
interfere with the ``MVar`` in the middle. The ``check`` and
``equivalentTo`` functions come from ``Test.DejaFu.Refinement`` (also
re-exported from ``Test.DejaFu``).
Signatures
----------
A signature tells the property-tester something about the state your
operation acts upon, it has a few components:
.. code-block:: haskell
data Sig s o x = Sig
{ initialise :: x -> ConcIO s
, observe :: s -> x -> ConcIO o
, interfere :: s -> x -> ConcIO ()
, expression :: s -> ConcIO ()
}
* ``s`` is the **state type**, it's the thing which your operations
mutate. For ``readMVar``, the state is some ``MVar a``.
* ``o`` is the **observation type**, it's some pure (and comparable)
proxy for a snapshot of your mutable state. For ``MVar a``, the
observation is probably a ``Maybe a``.
* ``x`` is the **seed type**, it's some pure value used to construct
the initial mutable state. For ``MVar a``, the seed is probably a
``Maybe a``.
* ``ConcIO`` is just one of the instances of ``MonadConc`` that Déjà
Fu defines for testing purposes. Just write code polymorphic in the
monad as usual, and all will work.
The ``initialise``, ``observe``, and ``expression`` functions should
be self-explanatory, but the ``interfere`` one may not be. It's the
job of the ``interfere`` function to change the state in some way;
it's run concurrently with the expression, to simulate the
nondeterministic action of other threads.
Here's a concrete example for our ``MVar`` example:
.. code-block:: haskell
sig :: (MVar ConcIO Int -> ConcIO a) -> Sig (MVar ConcIO Int) (Maybe Int) (Maybe Int)
sig e = Sig
{ initialise = maybe newEmptyMVar newMVar
, observe = \v _ -> tryTakeMVar v
, interfere = \v s -> tryTakeMVar v >> maybe (pure ()) (\x -> void $ tryPutMVar v (x * 1000)) s
, expression = void . e
}
The ``observe`` function should be deterministic, but as it is run
after the normal execution ends, it may have side-effects on the
state. The ``interfere`` function can do just about anything [#]_,
but a poor one may result in the property-checker being unable to
distinguish between atomic and nonatomic expressions.
.. [#] There are probably some concrete rules for a good function, but
I haven't figured them out yet.
Properties
----------
A property is a pair of signatures linked by one of three provided
functions. These functions are:
.. csv-table::
:header: "Function", "Operator", "Checks that..."
"``equivalentTo``", "``===``", "... the left and right have exactly the same behaviours"
"``refines``", "``=>=``", "... every behaviour of the left is also a behaviour of the right"
"``strictlyRefines``", "``->-``", "... ``left =>= right`` holds but ``left === right`` does not"
The signatures can have different state types, as long as the seed and
observation types are the same. This lets you compare different
implementations of the same idea: for example, comparing a concurrent
stack implemented using ``MVar`` with one implemented using ``IORef``.
Properties can have parameters, given in the obvious way:
.. code-block:: haskell
check $ \a b c -> sig1 ... `op` sig2 ...
Under the hood, seed and parameter values are generated using the
:hackage:`leancheck` package, an enumerative property-based testing
library. This means that any types you use will need to have a
``Listable`` instance.
You can also think about the three functions in terms of sets of
results, where a result is a ``(Maybe Failure, o)`` value. A
``Failure`` is something like deadlocking, or being killed by an
exception; ``o`` is the observation type. An observation is always
made, even if execution of the expression fails.
.. csv-table::
:header: "Function", "Result-set operation"
"``refines``", "For all seed and parameter assignments, subset-or-equal"
"``strictlyRefines``", "For at least one seed and parameter assignment, proper subset; for all others, subset-or-equal"
"``equivalentTo``", "For all seed and parameter assignments, equality"
Finally, there is an ``expectFailure`` function, which inverts the
expected result of a property.
The Déjà Fu testsuite has :github:`a collection of refinement
properties
<blob/2a15549d97c2fa12f5e8b92ab918fdb34da78281/dejafu-tests/Cases/Refinement.hs>`,
which may help you get a feel for this sort of testing.
Using HUnit and Tasty
---------------------
As for unit testing, :hackage:`HUnit` and :hackage:`tasty` integration
is provided for refinement testing in the :hackage:`hunit-dejafu` and
:hackage:`tasty-dejafu` packages.
The ``testProperty`` function is used to check properties. Our example from the start becomes:
.. code-block:: haskell
testProperty "Read is equivalent to Take then Put" prop_mvar_read_take_put

64
doc/release_process.rst
View File

@ -1,64 +0,0 @@
Release Process
===============
1. Figure out what the next version number is. See the PVP_ page if
unsure.
2. Update version numbers in the relevant cabal files:
* Update the ``version`` field
* Update the ``tag`` in the ``source-repository`` block
3. Fill in all ``@since unreleased`` Haddock comments with the
relevant version number.
4. Update version numbers in the tables in the README and the Getting
Started page.
5. Ensure the relevant CHANGELOG files have all the entries they
should.
6. Add the release information to the relevant CHANGELOG files:
* Change the ``unreleased`` title to the version number
* Add the current date
**If it's early in the year (like January or February), make sure
you don't put down the wrong year.**
* Add the git tag name
* Add the Hackage URL
* Add the contributors list
7. Commit.
8. Push to GitHub and wait for GitHub Actions to confirm everything is
OK. If it's not OK, fix what is broken before continuing.
9. Merge the PR.
10. Tag the merge commit. Tags are in the form
``<package>-<version>``, and the message is the changelog entry.
11. Push tags to GitHub.
When the merge commit successfully builds on ``master`` the updated
packages will be pushed to Hackage by Concourse.
Pro tips
--------
* If a release would have a combination of breaking and non-breaking
changes, if possible make two releases: the non-breaking ones first,
and then a major release with the breaking ones.
This makes it possible for users who don't want the breaking changes
to still benefit from the non-breaking improvements.
* Before uploading to Hackage, check you have no changes to the files
(for example, temporarily changing the GHC options, or adding
``trace`` calls, for debugging reasons).
``stack upload`` will upload the files on the disk, not the files in
version control, so your unwanted changes will be published!

115
doc/typeclass.rst
View File

@ -1,115 +0,0 @@
Typeclasses
===========
We don't use the regular ``Control.Concurrent`` and
``Control.Exception`` modules, we use typeclass-generalised ones
instead from the :hackage:`concurrency` and :hackage:`exceptions`
packages.
Porting guide
-------------
If you want to test some existing code, you'll need to port it to the
appropriate typeclass. The typeclass is necessary, because we can't
peek inside ``IO`` and ``STM`` values, so we need to able to plug in
an alternative implementation when testing.
Fortunately, this tends to be a fairly mechanical and type-driven
process:
1. Import ``Control.Concurrent.Classy.*`` instead of
``Control.Concurrent.*``
2. Import ``Control.Monad.Catch`` instead of ``Control.Exception``
3. Change your monad type:
* ``IO a`` becomes ``MonadConc m => m a``
* ``STM a`` becomes ``MonadSTM stm => stm a``
4. Parameterise your state types by the monad:
* ``TVar`` becomes ``TVar stm``
* ``MVar`` becomes ``MVar m``
* ``IORef`` becomes ``IORef m``
5. Some functions are renamed:
* ``forkIO*`` becomes ``fork*``
* ``atomicModifyIORefCAS*`` becomes ``modifyIORefCAS*``
6. Fix the type errors
If you're lucky enough to be starting a new concurrent Haskell
project, you can just program against the ``MonadConc`` interface.
What if I really need I/O?
--------------------------
You can use ``MonadIO`` and ``liftIO`` with ``MonadConc``, for
instance if you need to talk to a database (or just use some existing
library which needs real I/O).
To test ``IO``-using code, there are some rules you need to follow:
1. Given the same set of scheduling decisions, your ``IO`` code must
be deterministic [#]_
2. As dejafu can't inspect ``IO`` values, they should be kept small;
otherwise dejafu may miss buggy interleavings
3. You absolutely cannot block on the action of another thread inside
``IO``, or the test execution will just deadlock.
.. [#] This is only essential if you're using the systematic testing
(the default). Nondeterministic ``IO`` won't break the random
testing, it'll just make things more confusing.
Deriving your own instances
---------------------------
There are ``MonadConc`` and ``MonadSTM`` instances for many common
monad transformers. In the simple case, where you want an instance
for a newtype wrapper around a type that has an instance, you may be
able to derive it. For example:
.. code-block:: haskell
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE StandaloneDeriving #-}
{-# LANGUAGE UndecidableInstances #-}
data Env = Env
newtype MyMonad m a = MyMonad { runMyMonad :: ReaderT Env m a }
deriving (Functor, Applicative, Monad)
deriving instance MonadThrow m => MonadThrow (MyMonad m)
deriving instance MonadCatch m => MonadCatch (MyMonad m)
deriving instance MonadMask m => MonadMask (MyMonad m)
deriving instance MonadConc m => MonadConc (MyMonad m)
``MonadSTM`` needs a slightly different set of classes:
.. code-block:: haskell
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE StandaloneDeriving #-}
{-# LANGUAGE UndecidableInstances #-}
data Env = Env
newtype MyMonad m a = MyMonad { runMyMonad :: ReaderT Env m a }
deriving (Functor, Applicative, Monad, Alternative, MonadPlus)
deriving instance MonadThrow m => MonadThrow (MyMonad m)
deriving instance MonadCatch m => MonadCatch (MyMonad m)
deriving instance MonadSTM m => MonadSTM (MyMonad m)
Don't be put off by the use of ``UndecidableInstances``, it's safe
here.

250
doc/unit_testing.rst
View File

@ -1,250 +0,0 @@
Unit Testing
============
Writing tests with Déjà Fu is a little different to traditional unit
testing, as your test case may have multiple results. A "test" is a
combination of your code, and a predicate which says something about
the set of allowed results.
Most tests will look something like this:
.. code-block:: haskell
dejafu "Assert the thing holds" myPredicate myAction
The ``dejafu`` function comes from ``Test.DejaFu``. Another useful
function is ``dejafuWithSettings``; see :ref:`settings`.
Actions
-------
An action is just something with the type ``MonadConc m => m a``, or
``(MonadConc m, MonadIO m) => m a`` for some ``a`` that your chosen
predicate can deal with.
For example, some users on Reddit found a couple of apparent bugs in
the :hackage:`auto-update` package a while ago (`thread here`__). As
the package is simple and self-contained, I translated it to the
``MonadConc`` abstraction and wrote a couple of tests to replicate the
bugs. Here they are:
.. code-block:: haskell
deadlocks :: MonadConc m => m ()
deadlocks = do
auto <- mkAutoUpdate defaultUpdateSettings
auto
nondeterministic :: forall m. MonadConc m => m Int
nondeterministic = do
var <- newIORef 0
let settings = (defaultUpdateSettings :: UpdateSettings m ())
{ updateAction = atomicModifyIORef var (\x -> (x+1, x)) }
auto <- mkAutoUpdate settings
auto
auto
.. __: https://www.reddit.com/r/haskell/comments/2i5d7m/updating_autoupdate/
These actions action could be tested with ``autocheck``, and the
issues would be revealed. The use of ``ScopedTypeVariables`` in the
second is an unfortunate example of what can happen when everything
becomes more polymorphic. But other than that, note how there is no
special mention of Déjà Fu in the actions: it's just normal concurrent
Haskell, simply written against a different interface.
The modified package is included :github:`in the test suite
<blob/2a15549d97c2fa12f5e8b92ab918fdb34da78281/dejafu-tests/Examples/AutoUpdate.hs>`,
if you want to see the full code. [#]_
.. [#] The predicates in dejafu-tests are a little confusing, as
they're the opposite of what you would normally write! These
predicates are checking that the bug is found, not that the
code is correct.
If the RTS supports bound threads (the ``-threaded`` flag was passed
to GHC when linking), then the main thread of an action given to Déjà
Fu will be bound, and further bound threads can be forked with the
``forkOS`` functions. If not, then attempting to fork a bound thread
will raise an error.
Conditions
----------
When a concurrent program of type ``MonadConc m => m a`` is executed,
it may produce a value of type ``a``, or it may experience a
**condition** such as deadlock.
A condition does not necessarily cause your test to fail. It's
important to be aware of what exactly your test is testing, to avoid
drawing the wrong conclusions from a passing (or failing) test.
Setup and Teardown
------------------
Because dejafu drives the execution of the program under test, there
are some tricks available to you which are not possible using normal
concurrent Haskell.
If your test does some set-up work which is required for your test to
work, but which is not the actual thing you are testing, you can
define that as a **setup action**:
.. code-block:: haskell
withSetup
:: Program Basic n x
-- ^ Setup action
-> (x -> Program Basic n a)
-- ^ Main program
-> Program (WithSetup x) n a
dejafu will save the state at the end of the setup action, and
efficiently restore that state in subsequent runs of the same test
with a different schedule. This can be much more efficient than
dejafu running the setup action normally every single time.
If you want to examine some state you created in your setup action
even if your actual test case deadlocks or something, you can define a
**teardown action**:
.. code-block:: haskell
withSetupAndTeardown
:: Program Basic n x
-- ^ Setup action
-> (x -> Either Condition y -> Program Basic n a)
-- ^ Teardown action
-> (x -> Program Basic n y)
-- ^ Main program
-> Program (WithSetupAndTeardown x y) n a
The teardown action is always executed.
Finally, if you want to ensure that some invariant holds over some
shared state, you can define invariants in the setup action, which are
checked atomically during the main action:
.. code-block:: haskell
-- slightly contrived example
let setup = do
var <- newEmptyMVar
registerInvariant $ do
value <- inspectMVar var
when (x == Just 1) (throwM Overflow)
pure var
in withSetup setup $ \var -> do
fork $ putMVar var 0
fork $ putMVar var 1
tryReadMVar var
If the main action violates the invariant, it is terminated with an
``InvariantFailure`` condition, and any teardown action is run.
Predicates
----------
There are a few predicates built in, and some helpers to define your
own.
.. csv-table::
:widths: 25, 75
``abortsNever``,"checks that the computation never aborts"
``abortsAlways``,"checks that the computation always aborts"
``abortsSometimes``,"checks that the computation aborts at least once"
An **abort** is where the scheduler chooses to terminate execution
early. If you see it, it probably means that a test didn't terminate
before it hit the execution length limit. Aborts are hidden unless
you use explicitly enable them, see :ref:`settings`.
.. csv-table::
:widths: 25, 75
``deadlocksNever``,"checks that the computation never deadlocks"
``deadlocksAlways``,"checks that the computation always deadlocks"
``deadlocksSometimes``,"checks that the computation deadlocks at least once"
**Deadlocking** is where every thread becomes blocked. This can be,
for example, if every thread is trying to read from an ``MVar`` that
has been emptied.
.. csv-table::
:widths: 25, 75
``exceptionsNever``,"checks that the main thread is never killed by an exception"
``exceptionsAlways``,"checks that the main thread is always killed by an exception"
``exceptionsSometimes``,"checks that the main thread is killed by an exception at least once"
An uncaught **exception** in the main thread kills the process. These
can be synchronous (thrown in the main thread) or asynchronous (thrown
to it from a different thread).
.. csv-table::
:widths: 25, 75
``alwaysSame``,"checks that the computation is deterministic and always produces a value"
``alwaysSameOn f``,"is like ``alwaysSame``, but transforms the results with ``f`` first"
``alwaysSameBy f``,"is like ``alwaysSame``, but uses ``f`` instead of ``(==)`` to compare"
``notAlwaysSame``,"checks that the computation is nondeterministic"
``notAlwaysSameOn f``,"is like ``notAlwaysSame``, but transforms the results with ``f`` first"
``notAlwaysSameBy f``,"is like ``notAlwaysSame``, but uses ``f`` instead of ``(==)`` to compare"
Checking for **determinism** will also find nondeterministic failures:
deadlocking (for instance) is still a result of a test!
.. csv-table::
:widths: 25, 75
``alwaysTrue p``,"checks that ``p`` is true for every result"
``somewhereTrue p``,"checks that ``p`` is true for at least one result"
These can be used to check custom predicates. For example, you might
want all your results to be less than five.
.. csv-table::
:widths: 25, 75
``gives xs``,"checks that the set of results is exactly ``xs`` (which may include conditions)"
``gives' xs``,"checks that the set of results is exactly ``xs`` (which may not include conditions)"
These let you say exactly what you want the results to be. Your test
will fail if it has any extra results, or misses a result.
You can check multiple predicates against the same collection of
results using the ``dejafus`` and ``dejafusWithSettings`` functions.
These avoid recomputing the results, and so may be faster than
multiple ``dejafu`` / ``dejafuWithSettings`` calls; see
:ref:`performance`.
Using HUnit and Tasty
---------------------
By itself, Déjà Fu has no framework in place for named test groups and
parallel execution or anything like that. It does one thing and does
it well, which is running test cases for concurrent programs.
:hackage:`HUnit` and :hackage:`tasty` integration is provided to get
more of the features you'd expect from a testing framework.
The integration is provided by the :hackage:`hunit-dejafu` and
:hackage:`tasty-dejafu` packages.
There's a simple naming convention used: the ``Test.DejaFu`` function
``dejafuFoo`` is wrapped in the appropriate way and exposed as
``testDejafuFoo`` from ``Test.HUnit.DejaFu`` and
``Test.Tasty.DejaFu``.
Our example from the start becomes:
.. code-block:: haskell
testDejafu "Assert the thing holds" myPredicate myAction
The ``autocheck`` function is exposed as ``testAuto``.

12
doc/Makefile → docs/readthedocs/Makefile
View File

@ -1,12 +1,12 @@
# Minimal makefile for Sphinx documentation
#
# You can set these variables from the command line.
SPHINXOPTS =
SPHINXBUILD = sphinx-build
SPHINXPROJ = DjFu
SOURCEDIR = .
BUILDDIR = _build
# You can set these variables from the command line, and also
# from the environment for the first two.
SPHINXOPTS ?=
SPHINXBUILD ?= sphinx-build
SOURCEDIR = source
BUILDDIR = build
# Put it first so that "make" without argument is like "make help".
help:

2
docs/readthedocs/requirements.txt Normal file
View File

@ -0,0 +1,2 @@
sphinx==7.1.2
sphinx-rtd-theme==1.3.0rc1

23
docs/readthedocs/source/conf.py Normal file
View File

@ -0,0 +1,23 @@
# Configuration file for the Sphinx documentation builder.
# -- Project information
project = 'Déjà Fu'
copyright = 'Michael Walker (barrucadu)'
author = 'Michael Walker (barrucadu)'
release = 'HEAD'
version = 'HEAD'
# -- General configuration
extensions = []
templates_path = ['_templates']
# -- Options for HTML output
html_theme = 'sphinx_rtd_theme'
# -- Options for EPUB output
epub_show_urls = 'footnote'

10
docs/readthedocs/source/index.rst Normal file
View File

@ -0,0 +1,10 @@
The Déjà Fu documentation has moved!
====================================
[Déjà Fu is] A martial art in which the user's limbs move in time
as well as space, […] It is best described as "the feeling that
you have been kicked in the head this way before"
**Terry Pratchett, Thief of Time**
`Visit the new documentation website <https://dejafu.docs.barrucadu.co.uk/>`.