path: root/unit/atf-src/doc/atf-test-case.4

.\" Copyright (c) 2007 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND
.\" CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
.\" IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY
.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
.\" GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
.\" IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
.\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
.\" IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.Dd October 5, 2014
.Dt ATF-TEST-CASE 4
.Os
.Sh NAME
.Nm atf-test-case
.Nd generic description of test cases
.Sh DESCRIPTION
A
.Em 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.
.Pp
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
.Em header
is, basically, a declarative piece of code that defines several
properties to describe what the test case does and how it behaves.
In other words: it defines the test case's
.Em meta-data ,
further described in the
.Sx Meta-data
section.
The
.Em 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
.Em cleanup
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.
.Pp
It is extremely important to keep the separation between a test case's
header and body well-defined, because the header is
.Em 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.
.Pp
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.
.Ss 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).
.Pp
The possible exit status of a test case are one of the following:
.Bl -tag -width expectedXfailureXX
.It expected_death
The test case expects to terminate abruptly.
.It expected_exit
The test case expects to exit cleanly.
.It 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.
.It expected_signal
The test case expects to receive a signal that makes it terminate.
.It expected_timeout
The test case expects to execute for longer than its timeout.
.It passed
The test case was executed successfully.
The test program exits with a success error code.
.It skipped
The test case could not be executed because some preconditions 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
.Em reason ,
a message describing why the test was skipped.
The test program exits with a success error code.
.It failed
An error appeared during the execution of the test case.
This is always accompanied by a
.Em reason ,
a message describing why the test failed.
The test program exits with a failure error code.
.El
.Pp
The usefulness of the
.Sq 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
.Sq expected_*
result is trying to cover is fixed, then the test case will be reported as
.Sq failed
and the developer will have to adjust it to match its new condition.
.Pp
It is important to note that all
.Sq expected_*
results are only provided as a
.Em hint
to the caller; the caller must verify that the test case did actually terminate
as the expected condition says.
.Ss Input/output
Test cases are free to print whatever they want to their
.Xr stdout 4
and
.Xr stderr 4
file descriptors.
They are, in fact, encouraged to print status information as they execute
to keep the user informed of their actions.
This is specially important for long test cases.
.Pp
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.
.Pp
The standard input of the test cases is unconditionally connected to
.Sq /dev/zero .
.Ss Meta-data
The following list describes all meta-data properties interpreted
internally 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
.Sq X- .
.Bl -tag -width requireXmachineXX
.It descr
Type: textual.
Required.
.Pp
A brief textual description of the test case's purpose.
Will be shown to the user in reports.
Also good for documentation purposes.
.It has.cleanup
Type: boolean.
Optional.
.Pp
If set to true, specifies that the test case has a cleanup routine that has
to be executed by the runtime engine during the cleanup phase of the execution.
This property is automatically set by the framework when defining a test case
with a cleanup routine, so it should never be set by hand.
.It ident
Type: textual.
Required.
.Pp
The test case's identifier.
Must be unique inside the test program and should be short but descriptive.
.It require.arch
Type: textual.
Optional.
.Pp
A whitespace separated list of architectures that the test case can be run
under without causing errors due to an architecture mismatch.
.It require.config
Type: textual.
Optional.
.Pp
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
.Em skipped .
.It require.diskspace
Type: integer.
Optional.
Specifies the minimum amount of available disk space needed by the test.
The value can have a size suffix such as
.Sq K ,
.Sq M ,
.Sq G
or
.Sq T
to make the amount of bytes easier to type and read.
.It require.files
Type: textual.
Optional.
.Pp
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
.Em skipped .
.It require.machine
Type: textual.
Optional.
.Pp
A whitespace separated list of machine types that the test case can be run
under without causing errors due to a machine type mismatch.
.It 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
.Sq K ,
.Sq M ,
.Sq G
or
.Sq T
to make the amount of bytes easier to type and read.
.It require.progs
Type: textual.
Optional.
.Pp
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
.Ev PATH ,
or as absolute paths.
If any of the required programs is not found, the test case is
.Em skipped .
.It require.user
Type: textual.
Optional.
.Pp
The required privileges to execute the test case.
Can be one of
.Sq root
or
.Sq unprivileged .
.Pp
If the test case is running as a regular user and this property is
.Sq root ,
the test case is
.Em skipped .
.Pp
If the test case is running as root and this property is
.Sq unprivileged ,
the runtime engine will automatically drop the privileges if the
.Sq unprivileged-user
configuration property is set; otherwise the test case is
.Em skipped .
.It timeout
Type: integral.
Optional; defaults to
.Sq 300 .
.Pp
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
program.
It is not acceptable for these tests to stall the whole execution of the
test program.
.Pp
Can optionally be set to zero, in which case the test case has no run-time
limit.
This is discouraged.
.El
.Ss 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:
.Bl -tag -width LCXMESSAGESXX
.It Ev HOME
Set to the work directory's path.
.It Ev LANG
Undefined.
.It Ev LC_ALL
Undefined.
.It Ev LC_COLLATE
Undefined.
.It Ev LC_CTYPE
Undefined.
.It Ev LC_MESSAGES
Undefined.
.It Ev LC_MONETARY
Undefined.
.It Ev LC_NUMERIC
Undefined.
.It Ev LC_TIME
Undefined.
.It Ev TZ
Hardcoded to
.Sq UTC .
.El
.Ss 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).
.Ss File creation mode mask (umask)
Test cases are always executed with a file creation mode mask (umask) of
.Sq 0022 .
The test case's code is free to change this during execution.
.Sh SEE ALSO
.Xr atf-test-program 1