ATF-TEST-CASE(4) BSD Kernel Interfaces Manual ATF-TEST-CASE(4)NAMEatf-test-case — generic description of test cases
DESCRIPTION
A test case is a piece of code that stress-tests a specific feature of
the software. This feature is typically self-contained enough, either in
the amount of code that implements it or in the general idea that
describes it, to warrant its independent testing. Given this, test cases
are very fine-grained, but they attempt to group similar smaller tests
which are semantically related.
A test case is defined by three components regardless of the language it
is implemented in: a header, a body and a cleanup routine. The header
is, basically, a declarative piece of code that defines several proper‐
ties to describe what the test case does and how it behaves. In other
words: it defines the test case's meta-data, further described in the
Meta-data section. The body is the test case itself. It executes all
actions needed to reproduce the test, and checks for failures. This body
is only executed if the abstract conditions specified by the header are
met. The cleanup routine routine is a piece of code always executed
after the body, regardless of the exit status of the test case. It can
be used to undo side-effects of the test case. Note that almost all
side-effects of a test case are automatically cleaned up by the library;
this is explained in more detail in the rest of this document.
It is extremely important to keep the separation between a test case's
header and body well-defined, because the header is always parsed,
whereas the body is only executed when the conditions defined in the
header are met and when the user specifies that test case.
At last, test cases are always contained into test programs. The test
programs act as a front-end to them, providing a consistent interface to
the user and several APIs to ease their implementation.
Results
Upon termination, a test case reports a status and, optionally, a textual
reason describing why the test reported such status. The caller must
ensure that the test case really performed the task that its status
describes, as the test program may be bogus and therefore providing a
misleading result (e.g. providing a result that indicates success but the
error code of the program says otherwise).
The possible exit status of a test case are one of the following:
expected_death The test case expects to terminate abruptly.
expected_exit The test case expects to exit cleanly.
expected_failure The test case expects to exit with a controller
fatal/non-fatal failure. If this happens, the test
program exits with a success error code.
expected_signal The test case expects to receive a signal that makes
it terminate.
expected_timeout The test case expects to execute for longer than its
timeout.
passed The test case was executed successfully. The test
program exits with a success error code.
skipped The test case could not be executed because some pre‐
conditions were not met. This is not a failure
because it can typically be resolved by adjusting the
system to meet the necessary conditions. This is
always accompanied by a reason, a message describing
why the test was skipped. The test program exits
with a success error code.
failed An error appeared during the execution of the test
case. This is always accompanied by a reason, a mes‐
sage describing why the test failed. The test pro‐
gram exits with a failure error code.
The usefulness of the ‘expected_*’ results comes when writing test cases
that verify known failures caused, in general, due to programming errors
(aka bugs). Whenever the faulty condition that the expectation is trying
to convery is fixed, then the test case will be reported as ‘failed’ and
the developer will have to adjust it to match its new condition.
It is important to note that all ‘expected_*’ results are only provided
as a hint to the caller; the caller must verify that the test case did
actually terminate as the expected condition says.
Input/output
Test cases are free to print whatever they want to their stdout(4) and
stderr(4) file descriptors. They are, in fact, encouraged to print sta‐
tus information as they execute to keep the user informed of their
actions. This is specially important for long test cases.
Test cases will log their results to an auxiliary file, which is then
collected by the test program they are contained in. The developer need
not care about this as long as he uses the correct APIs to implement the
test cases.
The standard input of the test cases is unconditionally connected to
‘/dev/zero’.
Meta-data
The following list describes all meta-data properties interpreted inter‐
nally by ATF. You are free to define new properties in your test cases
and use them as you wish, but non-standard properties must be prefixed by
‘X-’.
descr Type: textual. Required.
A brief textual description of the test case's pur‐
pose. Will be shown to the user in reports. Also
good for documentation purposes.
has.cleanup Type: boolean. Optional.
If set to true, specifies that the test case has a
cleanup routine that has to be executed by atf-run(1)
during the cleanup phase of the execution. This prop‐
erty is automatically set by the framework when defin‐
ing a test case with a cleanup routine, so it should
never be set by hand.
ident Type: textual. Required.
The test case's identifier. Must be unique inside the
test program and should be short but descriptive.
require.arch Type: textual. Optional.
A whitespace separated list of architectures that the
test case can be run under without causing errors due
to an architecture mismatch.
require.config Type: textual. Optional.
A whitespace separated list of configuration variables
that must be defined to execute the test case. If any
of the required variables is not defined, the test
case is skipped.
require.files Type: textual. Optional.
A whitespace separated list of files that must be
present to execute the test case. The names of these
files must be absolute paths. If any of the required
files is not found, the test case is skipped.
require.machine Type: textual. Optional.
A whitespace separated list of machine types that the
test case can be run under without causing errors due
to a machine type mismatch.
require.memory Type: integer. Optional. Specifies the minimum
amount of physical memory needed by the test. The
value can have a size suffix such as ‘K’, ‘M’, ‘G’ or
‘T’ to make the amount of bytes easier to type and
read.
require.progs Type: textual. Optional.
A whitespace separated list of programs that must be
present to execute the test case. These can be given
as plain names, in which case they are looked in the
user's PATH, or as absolute paths. If any of the
required programs is not found, the test case is
skipped.
require.user Type: textual. Optional.
The required privileges to execute the test case. Can
be one of ‘root’ or ‘unprivileged’.
If the test case is running as a regular user and this
property is ‘root’, the test case is skipped.
If the test case is running as root and this property
is ‘unprivileged’, atf-run(1) will automatically drop
the privileges if the ‘unprivileged-user’ configura‐
tion property is set; otherwise the test case is
skipped.
timeout Type: integral. Optional; defaults to ‘300’.
Specifies the maximum amount of time the test case can
run. This is particularly useful because some tests
can stall either because they are incorrectly coded or
because they trigger an anomalous behavior of the pro‐
gram. It is not acceptable for these tests to stall
the whole execution of the test program.
Can optionally be set to zero, in which case the test
case has no run-time limit. This is discouraged.
Environment
Every time a test case is executed, several environment variables are
cleared or reseted to sane values to ensure they do not make the test
fail due to unexpected conditions. These variables are:
HOME Set to the work directory's path.
LANG Undefined.
LC_ALL Undefined.
LC_COLLATE Undefined.
LC_CTYPE Undefined.
LC_MESSAGES Undefined.
LC_MONETARY Undefined.
LC_NUMERIC Undefined.
LC_TIME Undefined.
TZ Hardcoded to ‘UTC’.
Work directories
The test program always creates a temporary directory and switches to it
before running the test case's body. This way the test case is free to
modify its current directory as it wishes, and the runtime engine will be
able to clean it up later on in a safe way, removing any traces of its
execution from the system. To do so, the runtime engine will perform a
recursive removal of the work directory without crossing mount points; if
a mount point is found, the file system will be unmounted (if possible).
File creation mode mask (umask)
Test cases are always executed with a file creation mode mask (umask) of
‘0022’. The test case's code is free to change this during execution.
SEE ALSOatf-run(1), atf-test-program(1), atf-formats(5), atf(7)BSD January 13, 2011 BSD
