deal.II has a testsuite with thousands of small programs that we run every time
we make a change to make sure
that no existing functionality is broken. It is located in the tests/
directory of the development repository. The expected output for
every test is stored in an *.output
next to the .cc
file,
and when running a test, you are notified if the output differs from the expected
output.
These days, every time we add a significant piece of functionality, we add at least one new test to the testsuite, and we also do so if we fix a bug, in both cases to make sure that future changes do not break this functionality (again). Machines running the testsuite submit the results to our cdash CDash instance, a webpage showing the status of our regression tests.
The testsuite is part of the development sources of deal.II and located
under the tests
subdirectory. The easiest way to obtain
both of them is to check out the current development sources via git:
$ git clone https://github.com/dealii/dealii
To enable the testsuite for a given build directory, ensure that deal.II is successfully configured and built (installation is not necessary). After that you can set up the testsuite via the "setup_tests" target:
$ make setup_testsThis will set up all tests supported by the current configuration. The testsuite can now be run in the current build directory as described below.
The setup can be fine-tuned using the following commands:
$ make prune_tests - removes all testsuite subprojects
In addition, when setting up the testsuite, the following environment
variables can be used to override default behavior when
calling make setup_tests
:
TEST_TIME_LIMIT - The time limit (in seconds) a single test is allowed to take. Defaults to 180 seconds TEST_PICKUP_REGEX - A regular expression to select only a subset of tests during setup. An empty string is interpreted as a catchall (this is the default).For example,
TEST_PICKUP_REGEX="umfpack" make setup_testswill only enable tests which match the string "umfpack" in category or name.
The testsuite can also be set up for an already installed library
(starting with version 8.3). For this, create a build directory for
the testsuite and run cmake pointing to the tests
subdirectory, e.g.,
$ mkdir tests_for_installed_dealii $ cd tests_for_installed_dealii $ cmake -DDEAL_II_DIR=/path/to/installed/dealii /path/to/dealii_source/testsAfter that the same configuration targets as described above are available.
The testsuite can now be run in the build directory via
$ ctest [-j N]Here,
N
is the number of concurrent tests that should be
run, in the same way as you can say make -jN
. The testsuite
is huge and will need around 12h on current computers
running single threaded.
If you only want to run a subset of tests matching a regular expression, or if you want to exclude tests matching a regular expression, you can use
$ ctest [-j N] -R '<positive regular expression>' $ ctest [-j N] -E '<negative regular expression>'
Note:
Not all tests succeed on every machine even if all computations are
correct, because your machine generates slightly different floating
point outputs. To increase the number of tests that work correctly,
install the
numdiff tool that compares
stored and newly created output files based on floating point
tolerances. To use it, simply export where the numdiff
executable can be found via the PATH
environment variable so that it can be found during
make setup_tests
.
A typical output of a ctest
invocation looks like:
$ ctest -j4 -R "base/thread_validity" Test project /tmp/trunk/build Start 747: base/thread_validity_01.debug Start 748: base/thread_validity_01.release Start 775: base/thread_validity_05.debug Start 776: base/thread_validity_05.release 1/24 Test #776: base/thread_validity_05.release ... Passed 1.89 sec 2/24 Test #748: base/thread_validity_01.release ... Passed 1.89 sec Start 839: base/thread_validity_03.debug Start 840: base/thread_validity_03.release 3/24 Test #747: base/thread_validity_01.debug ..... Passed 2.68 sec [...] Start 1077: base/thread_validity_08.debug Start 1078: base/thread_validity_08.release 16/24 Test #1078: base/thread_validity_08.release ...***Failed 2.86 sec 18/24 Test #1077: base/thread_validity_08.debug .....***Failed 3.97 sec [...] 92% tests passed, 2 tests failed out of 24 Total Test time (real) = 20.43 sec The following tests FAILED: 1077 - base/thread_validity_08.debug (Failed) 1078 - base/thread_validity_08.release (Failed) Errors while running CTestIf a test failed (like
base/thread_validity_08.debug
in above
example output), you might want to find out what exactly went wrong. To
this end, you can search
through Testing/Temporary/LastTest.log
for the exact output
of the test, or you can rerun this one test, specifying -V
to select verbose output of tests:
$ ctest -V -R "base/thread_validity_08.debug" [...] test 1077 Start 1077: base/thread_validity_08.debug 1077: Test command: [...] 1077: Test timeout computed to be: 600 1077: Test base/thread_validity_08.debug: RUN 1077: =============================== OUTPUT BEGIN =============================== 1077: Built target thread_validity_08.debug 1077: Generating thread_validity_08.debug/output 1077: terminate called without an active exception 1077: /bin/sh: line 1: 18030 Aborted [...]/thread_validity_08.debug 1077: base/thread_validity_08.debug: BUILD successful. 1077: base/thread_validity_08.debug: RUN failed. Output: 1077: DEAL::OK. 1077: gmake[3]: *** [thread_validity_08.debug/output] Error 1 1077: gmake[2]: *** [CMakeFiles/thread_validity_08.debug.diff.dir/all] Error 2 1077: gmake[1]: *** [CMakeFiles/thread_validity_08.debug.diff.dir/rule] Error 2 1077: gmake: *** [thread_validity_08.debug.diff] Error 2 1077: 1077: 1077: base/thread_validity_08.debug: ****** RUN failed ******* 1077: 1077: =============================== OUTPUT END ===============================So this specific test aborted in the
RUN
stage.
The general output for a successful test <test>
in
category <category>
for build type
<build>
is
xx: Test <category>/<test>.<build>: PASSED xx: =============================== OUTPUT BEGIN =============================== xx: [...] xx: <category>/<test>.<build>: PASSED. xx: =============================== OUTPUT END ===============================And for a test that fails in stage
<stage>
:
xx: Test <category>/<test>.<build>: <stage> xx: =============================== OUTPUT BEGIN =============================== xx: [...] xx: <category>/<test>.<build>: <stage> failed. [...] xx: xx: <category>/<test>.<build>: ****** <stage> failed ******* xx: =============================== OUTPUT END ===============================Hereby,
<stage>
indicates the stage in which the
test failed:
CONFIGURE
: only for test in the "build_tests"
category: The test project failed in the configuration stage
BUILD
: compilation error occurred
RUN
: the test executable could not be run / aborted
DIFF
: the test output differs from the reference output
PASSED
: the test run successful
The testsuite can also be run using valgrind to check for memory corruption in the library.
You can do so by invoking
ctest -DMEMORYCHECK=ON <...> -S ../tests/run_testsuite.cmakewhen running the testsuite, or directly by
ctest <...> -S ../tests/run_memorycheck.cmake
At the end of all of this, results will be shown in a separate section "Dynamic Analysis" at the deal.II cdash site.
The testsuite can also be used to provide coverage information, i.e., data that shows which lines of the library are executed how many times by running through all of the tests in the testsuite. This is of interest in finding places in the library that are not covered by the testsuite and, consequently, are prone to the inadvertent introduction of bugs since existing functionality is not subject to existing tests.
To run the testsuite in this mode, essentially, you have to do three things:
cmake -DCMAKE_BUILD_TYPE=Debug -DDEAL_II_SETUP_COVERAGE=ON <...>You can then build the library and run the tests as usual.
For the last point, one can in principal use whatever tool one wants. That said, the deal.II ctest driver already has builtin functionality to gather all profiling files and submit them to cdash where we already gather testsuite results (see below). You can do so by invoking
ctest -DCOVERAGE=ON <...> -S ../tests/run_testsuite.cmakewhen running the testsuite, or directly by
ctest <...> -S ../tests/run_coverage.cmake
At the end of all of this, results will be shown in a separate section
"Coverage" at the
deal.II cdash site.
In case you download the coverage report uploader for Codecov via
contrib/utilities/download_codecov
, the coverage
report will also be uploaded to the
Codecov dashboard.
The following outlines what you need to know if you want to understand how the testsuite actually works, for example because you may want to add tests along with the functionality you are currently developing.
A test usually consists of a source file and an output file for
comparison (under the testsuite directory tests
):
category/test.cc category/test.output
category
will be one of the existing subdirectory
under tests/
, e.g., lac/
, base/
,
or mpi/
. Historically, we have grouped tests into the
directories base/, lac/, deal.II/
depending on their
functionality, and bits/
if they were small unit tests, but
in practice we have not always followed this rigidly. There are also
more specialized directories trilinos/, petsc/,
serialization/, mpi/
etc, whose meaning is more obvious.
test.cc
must be a regular executable (i.e. having an
int main()
routine). It will be compiled, linked and
run. The executable should not output anything to cout
(at least under normal circumstances, i.e. no error condition),
instead the executable should output to a file output
in the current working directory. In practice, we rarely write the
source files completely from scratch, but we find an existing test that
already does something similar and copy/modify it to fit our needs.
For a normal test, ctest
will typically run the following 3
stages:
BUILD
: The build stage generates an executable in
BUILD_DIR/tests/<category>/<test>
.
RUN
: The run stage then invokes the executable in
the directory where it is located. By convention, each test
either prints its test results directly to stdout
,
or directly into a file called output
(in the
current working directory). The latter takes precedence.
The output (via stdout or file) will then be located in
BUILD_DIR/tests/<category>/<test>/output
.
If the run fails (e.g. because the program aborts with an error
code) the file output
is renamed to
failing_output
.
DIFF
: As a last stage the generated output file will
be compared to
SOURCE_DIR/tests/<category>/<test>[...].output
.
and stored in
BUILD_DIR/tests/<category>/<test>/diff
.
If the diff fails the file diff
is renamed to
failing_diff
.
Comparison file can actually be named in a more complex way than
just category/test.output
. In pseudo code:
category/test.[with_<string>(<=|>=|=|<|>)<on|off|version>.]* [mpirun=<x>.][expect=<y>.][binary.][<debug|release>.]outputNormally, a test will be set up so that it runs twice, once in debug and once in release configuration. If a specific test can only be run in debug or release configurations but not in both it is possible to restrict the setup by prepending
.debug
or .release
directly before
.output
, e.g.:
category/test.debug.outputThis way, the test will only be set up to build and run against the debug library. If a test should run in both configurations but, for some reason, produces different output (e.g., because it triggers an assertion in debug mode), then you can just provide two different output files:
category/test.debug.output category/test.release.output
In a similar vain as for build configurations, it is possible to restrict tests to specific feature configurations, e.g.,
category/test.with_umfpack=on.output, or category/test.with_zlib=off.outputThese tests will only be set up if the specified feature was configured. It is possible to provide different output files for disabled/enabled features, e.g.,
category/test.with_64bit_indices=on.output category/test.with_64bit_indices=off.outputFurthermore, a test can be restricted to be run only if specific versions of a feature are available. For example
category/test.with_trilinos.geq.11.14.1.outputwill only be run if (a) trilinos is available, i.e.,
DEAL_II_WITH_TRILINOS=TRUE
and (b) if trilinos is at least
of version 11.14.1. Supported operators are
=
, .le.;
, .ge.
, .leq.
,
.geq.
.
It is also possible to declare multiple constraints subsequently, e.g.
category/test.with_umfpack=on.with_zlib=on.output
Note: The tests in some subdirectories of tests/
are
automatically run only if some feature is enabled. In this case a
feature constraint encoded in the output file name is redundant and
should be avoided. In particular, this holds for subdirectories
distributed_grids
, lapack
,
metis
, petsc
, slepc
,
trilinos
, umfpack
, gla
, and
mpi
If a test should be run with MPI in parallel, the number of MPI
processes N
with which a program needs to be run for
comparison with a given output file is specified as follows:
category/test.mpirun=N.outputIt is quite typical for an MPI-enabled test to have multiple output files for different numbers of MPI processes.
Sometimes it is necessary to provide multiple comparison files for a
single test, for example because you want to test code on multiple
platforms that produce different output files that, nonetheless, all
should be considered correct. An example would be tests that use the
rand()
function that is implemented differently on
different platforms. Additional comparison files have the same path
as the main comparison file (in this case test.output
)
followed by a dot and a variant description:
category/test.output category/test.output.2 category/test.output.3 category/test.output.4The testsuite will try to match the output against all variants in alphabetical order starting with the main output file.
Warning: This mechanism is only meant as a last resort for tests where no alternative approach is viable. Especially, consider first to
Note: The main comparison file (i.e., the one ending in
output
is mandatory. Otherwise, no test will be
configured.
Normally a test is considered to be successful if all test stages
could be run and the test reached the PASSED
stage (see
the output description section for details).
If (for some reason) the test should succeed ending at a specific
test stage different than PASSED
you can specify it via
expect=<stage>
, e.g.:
category/test.expect=run.output
We typically add one or more new tests every time we add new functionality to the library or fix a bug. If you want to contribute code to the library, you should do this as well. Here's how: you need a testcase and a file with the expected output.
For the testcase, we usually start from one of the existing tests, copy and modify it to where it does what we'd like to test. Alternatively, you can also start from a template like this:
// --------------------------------------------------------------------- // // Copyright (C) 2015 - 2020 by the deal.II Authors // // This file is part of the deal.II library. // // The deal.II library is free software; you can use it, redistribute // it, and/or modify it under the terms of the GNU Lesser General // Public License as published by the Free Software Foundation; either // version 2.1 of the License, or (at your option) any later version. // The full text of the license can be found in the file LICENSE.md at // the top level directory of deal.II. // // --------------------------------------------------------------------- // a short (a few lines) description of what the program does #include "../tests.h" // all include files you need here int main () { // Initialize deallog for test output. // This also reroutes deallog output to a file "output". initlog(); // your testcode here: int i = 0; deallog << i << std::endl; return 0; }
This code opens an output file output
in the current working
directory and then writes all output you generate to it, through the
deallog
stream. The deallog
stream works like
any other std::ostream
except that it does a few more
things behind the scenes that are helpful in this context. In above
case, we only write a zero to the output file. Most tests of course
write computed data to the output file to make sure that whatever we
compute is what we got when the test was first written.
There are a number of directories where you can put a new test.
Extensive tests of individual classes or groups of classes
have traditionally been into the base/
,
lac/
, deal.II/
, fe/
,
hp/
, or multigrid/
directories, depending on
where the classes that are tested are located. More atomic tests often go
into bits/
. There are also
directories for PETSc and Trilinos wrapper functionality.
In order to run your new test, copy it to an appropriate category and create an empty comparison file for it:
category/my_new_test.cc category/my_new_test.outputNow, rerun
$ make setup_testsso that your new test is picked up. After that it is possible to invoke it with
$ ctest -V -R "category/my_new_test"
If you run your new test executable this way, the test should compile
and run successfully but fail in the diff stage (because of the empty
comparison file). You will get an output file
BUILD_DIR/category/my_new_test/output
. Take a look at it to
make sure that the output is what you had expected. (For complex tests,
it may sometimes be impossible to say whether the output is correct, and
in this case we sometimes just take it to make
sure that future invocations of the test yield the same results.)
The next step is to copy and rename this output file to the source directory and replace the original comparison file with it:
category/my_new_test.outputAt this point running the test again should be successful:
$ ctest -V -R "category/my_new_test"
If you want to create a new category in the testsuite, create an new
folder under CMakeLists.txt
file into it containing
CMAKE_MINIMUM_REQUIRED(VERSION 2.8.12) INCLUDE(../setup_testsubproject.cmake) PROJECT(testsuite CXX) INCLUDE(${DEAL_II_TARGET_CONFIG}) DEAL_II_PICKUP_TESTS()
To submit test results to our CDash
instance just invoke ctest within a build directory (or designated
build directory) with the -S
option pointing to the
run_testsuite.cmake
script (assuming here for the
moment that your build directory is a sub-directory of the
source directory):
$ ctest [...] -V -S ../tests/run_testsuite.cmakeThe script will run configure, build and ctest and submit the results to the CDash server. It does not matter whether the configure, build or ctest stages were run before that. Also in script mode, you can specify the same options for
ctest
as explained above.
Note: For also building the tests in parallel you have to provide suitable flags using MAKEOPTS as well, i.e. you would typically use
$ ctest -DMAKEOPTS="-j N" -j N [...] -V -S ../tests/run_testsuite.cmakefor compiling the library and running the tests in parallel, where
N
is the number of jobs you want to
simultaneously execute on your machine; you would typically
choose N
equal to the number of processor cores you
have in your machine, or maybe somewhere around one half to
three quarters if you don't want to overload it or are short on
memory.
It is possible to run tests and submit results for an already installed library by
mkdir build && cd build cp $DEAL_II_SOURCE_DIR/CTestConfig.cmake . ctest \ -DCTEST_SOURCE_DIRECTORY=$DEAL_II_SOURCE_DIR/tests \ -DDEAL_II_DIR=$DEAL_II_DIR \ [...] -S $DEAL_II_SOURCE_DIR/tests/run_testsuite.cmake -V
Note: The default output in script mode is very minimal.
Therefore, it is recommended to specify -V
which will
give the same level of verbosity as the non-script mode.
Note: The following variables can be set to via
ctest -D<variable>=<value> [...]to control the behaviour of the
run_testsuite.cmake
script:
CTEST_SOURCE_DIRECTORY - The source directory of deal.II - If unspecified, "../" relative to the location of this script is used. If this is not a source directory, an error is thrown. CTEST_BINARY_DIRECTORY - The designated build directory (already configured, empty, or non existent - see the information about TRACKs what will happen) - If unspecified the current directory is used. If the current directory is equal to CTEST_SOURCE_DIRECTORY or the "tests" directory, an error is thrown. CTEST_CMAKE_GENERATOR - The CMake Generator to use (e.g. "Unix Makefiles", or "Ninja", see $ man cmake) - If unspecified the generator of a configured build directory will be used, otherwise "Unix Makefiles". TRACK - The track the test should be submitted to. Defaults to "Experimental". Possible values are: "Experimental" - all tests that are not specifically "build" or "regression" tests should go into this track "Build Tests" - Build tests that configure and build in a clean directory (without actually running the testsuite) "Regression Tests" - Reserved for the "official" regression tester "Continuous" - Reserved for the "official" regression tester CONFIG_FILE - A configuration file (see doc/users/config.sample) that will be used during the configuration stage (invokes $ cmake -C ${CONFIG_FILE}). This only has an effect if CTEST_BINARY_DIRECTORY is empty. DESCRIPTION - A string that is appended to CTEST_BUILD_NAME COVERAGE - If set to ON deal.II will be configured with DEAL_II_SETUP_COVERAGE=ON, CMAKE_BUILD_TYPE=Debug and the CTEST_COVERAGE() stage will be run. Test results must go into the "Experimental" section. MAKEOPTS - Additional options that will be passed directly to make (or ninja).Furthermore, the variables TEST_TIME_LIMIT and TEST_PICKUP_REGEX (as described above), DIFF_DIR, and NUMDIFF_DIR can also be set and will be handed automatically down to
cmake
. For more details on the different tracks, see
the
Testing Infrastructure Wiki page.
Build tests are used to check that deal.II can be compiled on different systems and with different compilers as well as different configuration options. Results are collected in the "Build Tests" track in CDash.
Running the build test suite is simple and we encourage deal.II
users with configurations not found on the CDash page to
participate. Assuming you checked out deal.II into the directory
dealii
, running it is as simple as:
mkdir dealii/build cd dealii/build ctest -j4 -S ../tests/run_buildtest.cmake
What this does is to compile and build deal.II in the directory
build
(which includes building all configurable tutorial
programs as well) but does not run the full testsuite. The results
are sent to the CDash instance.
Note: Build tests require the designated build directory to be completely empty. If you want to specify a build configuration for cmake use a configuration file to preseed the cache as explained above:
$ ctest -DCONFIG_FILE="[...]/config.sample" [...]
Build tests work best if they run automatically and periodically. There is a detailed example for such dedicated build tests on the wiki.