ATF-SH-API(3) BSD Library Functions Manual ATF-SH-API(3)NAME
atf_add_test_case, atf_check, atf_check_equal, atf_config_get,
atf_config_has, atf_expect_death, atf_expect_exit, atf_expect_fail,
atf_expect_pass, atf_expect_signal, atf_expect_timeout, atf_fail,
atf_get, atf_get_srcdir, atf_pass, atf_require_prog, atf_set, atf_skip,
atf_test_case — POSIX shell API to write ATF-based test programs
SYNOPSISatf_add_test_case(name);
atf_check(command);
atf_check_equal(expr1, expr2);
atf_config_get(var_name);
atf_config_has(var_name);
atf_expect_death(reason, ...);
atf_expect_exit(exitcode, reason, ...);
atf_expect_fail(reason, ...);
atf_expect_pass();
atf_expect_signal(signo, reason, ...);
atf_expect_timeout(reason, ...);
atf_fail(reason);
atf_get(var_name);
atf_get_srcdir();
atf_pass();
atf_require_prog(prog_name);
atf_set(var_name, value);
atf_skip(reason);
atf_test_case(name, cleanup);
DESCRIPTION
ATF provides a simple but powerful interface to easily write test pro‐
grams in the POSIX shell language. These are extremely helpful given
that they are trivial to write due to the language simplicity and the
great deal of available external tools, so they are often ideal to test
other applications at the user level.
Test programs written using this library must be run using the atf-sh(1)
interpreter by putting the following on their very first line:
#! /usr/bin/env atf-sh
Shell-based test programs always follow this template:
atf_test_case tc1
tc1_head() {
... first test case's header ...
}
tc1_body() {
... first test case's body ...
}
atf_test_case tc2 cleanup
tc2_head() {
... second test case's header ...
}
tc2_body() {
... second test case's body ...
}
tc2_cleanup() {
... second test case's cleanup ...
}
... additional test cases ...
atf_init_test_cases() {
atf_add_test_case tc1
atf_add_test_case tc2
... add additional test cases ...
}
Definition of test cases
Test cases have an identifier and are composed of three different parts:
the header, the body and an optional cleanup routine, all of which are
described in atf-test-case(4). To define test cases, one can use the
atf_test_case() function, which takes a first parameter specifiying the
test case's name and instructs the library to set things up to accept it
as a valid test case. The second parameter is optional and, if provided,
must be ‘cleanup’; providing this parameter allows defining a cleanup
routine for the test case. It is important to note that this function
does not set the test case up for execution when the program is run. In
order to do so, a later registration is needed through the
atf_add_test_case() function detailed in Program initialization.
Later on, one must define the three parts of the body by providing two or
three functions (remember that the cleanup routine is optional). These
functions are named after the test case's identifier, and are
<id>_head(), <id>_body() and <id>_cleanup.() None of these take parame‐
ters when executed.
Program initialization
The test program must define an atf_init_test_cases() function, which is
in charge of registering the test cases that will be executed at run time
by using the atf_add_test_case() function, which takes the name of a test
case as its single parameter. This main function should not do anything
else, except maybe sourcing auxiliary source files that define extra
variables and functions.
Configuration variables
The test case has read-only access to the current configuration variables
through the atf_config_has() and atf_config_get() methods. The former
takes a single parameter specifying a variable name and returns a boolean
indicating whether the variable is defined or not. The latter can take
one or two parameters. If it takes only one, it specifies the variable
from which to get the value, and this variable must be defined. If it
takes two, the second one specifies a default value to be returned if the
variable is not available.
Access to the source directory
It is possible to get the path to the test case's source directory from
anywhere in the test program by using the atf_get_srcdir() function. It
is interesting to note that this can be used inside atf_init_test_cases()
to silently include additional helper files from the source directory.
Requiring programs
Aside from the require.progs meta-data variable available in the header
only, one can also check for additional programs in the test case's body
by using the atf_require_prog() function, which takes the base name or
full path of a single binary. Relative paths are forbidden. If it is
not found, the test case will be automatically skipped.
Test case finalization
The test case finalizes either when the body reaches its end, at which
point the test is assumed to have passed, or at any explicit call to
atf_pass(), atf_fail() or atf_skip(). These three functions terminate
the execution of the test case immediately. The cleanup routine will be
processed afterwards in a completely automated way, regardless of the
test case's termination reason.
atf_pass() does not take any parameters. atf_fail() and atf_skip() take
a single string parameter that describes why the test case failed or was
skipped, respectively. It is very important to provide a clear error
message in both cases so that the user can quickly know why the test did
not pass.
Expectations
Everything explained in the previous section changes when the test case
expectations are redefined by the programmer.
Each test case has an internal state called ‘expect’ that describes what
the test case expectations are at any point in time. The value of this
property can change during execution by any of:
atf_expect_death(reason, ...)
Expects the test case to exit prematurely regardless of the
nature of the exit.
atf_expect_exit(exitcode, reason, ...)
Expects the test case to exit cleanly. If exitcode is not ‘-1’,
atf-run(1) will validate that the exit code of the test case
matches the one provided in this call. Otherwise, the exact
value will be ignored.
atf_expect_fail(reason)
Any failure raised in this mode is recorded, but such failures do
not report the test case as failed; instead, the test case final‐
izes cleanly and is reported as ‘expected failure’; this report
includes the provided reason as part of it. If no error is
raised while running in this mode, then the test case is reported
as ‘failed’.
This mode is useful to reproduce actual known bugs in tests.
Whenever the developer fixes the bug later on, the test case will
start reporting a failure, signaling the developer that the test
case must be adjusted to the new conditions. In this situation,
it is useful, for example, to set reason as the bug number for
tracking purposes.
atf_expect_pass()
This is the normal mode of execution. In this mode, any failure
is reported as such to the user and the test case is marked as
‘failed’.
atf_expect_signal(signo, reason, ...)
Expects the test case to terminate due to the reception of a sig‐
nal. If signo is not ‘-1’, atf-run(1) will validate that the
signal that terminated the test case matches the one provided in
this call. Otherwise, the exact value will be ignored.
atf_expect_timeout(reason, ...)
Expects the test case to execute for longer than its timeout.
Helper functions for common checks
atf_check([options], command, [args])
This function wraps the execution of the atf-check tool and makes the
test case fail if the tool reports failure. You should always use this
function instead of the tool in your scripts. For more details on the
parameters of this function, refer to atf-check(1).
atf_check_equal(expr1, expr2)
This function takes two expressions, evaluates them and, if their results
differ, aborts the test case with an appropriate failure message.
EXAMPLES
The following shows a complete test program with a single test case that
validates the addition operator:
atf_test_case addition
addition_head() {
atf_set "descr" "Sample tests for the addition operator"
}
addition_body() {
atf_check_equal $((0 + 0)) 0
atf_check_equal $((0 + 1)) 1
atf_check_equal $((1 + 0)) 0
atf_check_equal $((1 + 1)) 2
atf_check_equal $((100 + 200)) 300
}
atf_init_test_cases() {
atf_add_test_case addition
}
This other example shows how to include a file with extra helper func‐
tions in the test program:
... definition of test cases ...
atf_init_test_cases() {
. $(atf_get_srcdir)/helper_functions.sh
atf_add_test_case foo1
atf_add_test_case foo2
}
This example demonstrates the use of the very useful atf_check() func‐
tion:
# Check for silent output
atf_check 'true' 0 null null
# Check for silent output and failure
atf_check 'false' 1 null null
# Check for known stdout and silent stderr
echo foo >expout
atf_check 'echo foo' 0 expout null
# Generate a file for later inspection
atf_check 'ls' 0 stdout null
grep foo ls || atf_fail "foo file not found in listing"
SEE ALSOatf-sh(1), atf-test-program(1), atf-test-case(4), atf(7)BSD June 28, 2010 BSD
