Provided by: libatf-dev_0.21-1build1_amd64 
NAME
atf-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 properties 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 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 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 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 message describing why the test failed. The
test program 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 ‘expected_*’ result is trying to cover 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 status 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 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 ‘X-’.
descr Type: textual. Required.
A brief textual description of the test case's purpose. 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 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.
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.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 ‘K’,
‘M’, ‘G’ or ‘T’ to make the amount of bytes easier to type and read.
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’,
the runtime engine will automatically drop the privileges if the
‘unprivileged-user’ configuration 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
program. 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 ALSO
atf-test-program(1)