linux/lib/kunit/kunit-example-test.c
Daniel Latypov 1cdba21db2 kunit: add ability to specify suite-level init and exit functions
KUnit has support for setup/cleanup logic for each test case in a suite.
But it lacks the ability to specify setup/cleanup for the entire suite
itself.

This can be used to do setup that is too expensive or cumbersome to do
for each test.
Or it can be used to do simpler things like log debug information after
the suite completes.
It's a fairly common feature, so the lack of it is noticeable.

Some examples in other frameworks and languages:
* https://docs.python.org/3/library/unittest.html#setupclass-and-teardownclass
* https://google.github.io/googletest/reference/testing.html#Test::SetUpTestSuite

Meta:
This is very similar to this patch here: https://lore.kernel.org/linux-kselftest/20210805043503.20252-3-bvanassche@acm.org/
The changes from that patch:
* pass in `struct kunit *` so users can do stuff like
  `kunit_info(suite, "debug message")`
* makes sure the init failure is bubbled up as a failure
* updates kunit-example-test.c to use a suite init
* Updates kunit/usage.rst to mention the new support
* some minor cosmetic things
  * use `suite_{init,exit}` instead of `{init/exit}_suite`
  * make suite init error message more consistent w/ test init
  * etc.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-05-02 12:35:51 -06:00

180 lines
5.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Example KUnit test to show how to use KUnit.
*
* Copyright (C) 2019, Google LLC.
* Author: Brendan Higgins <brendanhiggins@google.com>
*/
#include <kunit/test.h>
/*
* This is the most fundamental element of KUnit, the test case. A test case
* makes a set EXPECTATIONs and ASSERTIONs about the behavior of some code; if
* any expectations or assertions are not met, the test fails; otherwise, the
* test passes.
*
* In KUnit, a test case is just a function with the signature
* `void (*)(struct kunit *)`. `struct kunit` is a context object that stores
* information about the current test.
*/
static void example_simple_test(struct kunit *test)
{
/*
* This is an EXPECTATION; it is how KUnit tests things. When you want
* to test a piece of code, you set some expectations about what the
* code should do. KUnit then runs the test and verifies that the code's
* behavior matched what was expected.
*/
KUNIT_EXPECT_EQ(test, 1 + 1, 2);
}
/*
* This is run once before each test case, see the comment on
* example_test_suite for more information.
*/
static int example_test_init(struct kunit *test)
{
kunit_info(test, "initializing\n");
return 0;
}
/*
* This is run once before all test cases in the suite.
* See the comment on example_test_suite for more information.
*/
static int example_test_init_suite(struct kunit_suite *suite)
{
kunit_info(suite, "initializing suite\n");
return 0;
}
/*
* This test should always be skipped.
*/
static void example_skip_test(struct kunit *test)
{
/* This line should run */
kunit_info(test, "You should not see a line below.");
/* Skip (and abort) the test */
kunit_skip(test, "this test should be skipped");
/* This line should not execute */
KUNIT_FAIL(test, "You should not see this line.");
}
/*
* This test should always be marked skipped.
*/
static void example_mark_skipped_test(struct kunit *test)
{
/* This line should run */
kunit_info(test, "You should see a line below.");
/* Skip (but do not abort) the test */
kunit_mark_skipped(test, "this test should be skipped");
/* This line should run */
kunit_info(test, "You should see this line.");
}
/*
* This test shows off all the types of KUNIT_EXPECT macros.
*/
static void example_all_expect_macros_test(struct kunit *test)
{
/* Boolean assertions */
KUNIT_EXPECT_TRUE(test, true);
KUNIT_EXPECT_FALSE(test, false);
/* Integer assertions */
KUNIT_EXPECT_EQ(test, 1, 1); /* check == */
KUNIT_EXPECT_GE(test, 1, 1); /* check >= */
KUNIT_EXPECT_LE(test, 1, 1); /* check <= */
KUNIT_EXPECT_NE(test, 1, 0); /* check != */
KUNIT_EXPECT_GT(test, 1, 0); /* check > */
KUNIT_EXPECT_LT(test, 0, 1); /* check < */
/* Pointer assertions */
KUNIT_EXPECT_NOT_ERR_OR_NULL(test, test);
KUNIT_EXPECT_PTR_EQ(test, NULL, NULL);
KUNIT_EXPECT_PTR_NE(test, test, NULL);
KUNIT_EXPECT_NULL(test, NULL);
KUNIT_EXPECT_NOT_NULL(test, test);
/* String assertions */
KUNIT_EXPECT_STREQ(test, "hi", "hi");
KUNIT_EXPECT_STRNEQ(test, "hi", "bye");
/*
* There are also ASSERT variants of all of the above that abort test
* execution if they fail. Useful for memory allocations, etc.
*/
KUNIT_ASSERT_GT(test, sizeof(char), 0);
/*
* There are also _MSG variants of all of the above that let you include
* additional text on failure.
*/
KUNIT_EXPECT_GT_MSG(test, sizeof(int), 0, "Your ints are 0-bit?!");
KUNIT_ASSERT_GT_MSG(test, sizeof(int), 0, "Your ints are 0-bit?!");
}
/*
* Here we make a list of all the test cases we want to add to the test suite
* below.
*/
static struct kunit_case example_test_cases[] = {
/*
* This is a helper to create a test case object from a test case
* function; its exact function is not important to understand how to
* use KUnit, just know that this is how you associate test cases with a
* test suite.
*/
KUNIT_CASE(example_simple_test),
KUNIT_CASE(example_skip_test),
KUNIT_CASE(example_mark_skipped_test),
KUNIT_CASE(example_all_expect_macros_test),
{}
};
/*
* This defines a suite or grouping of tests.
*
* Test cases are defined as belonging to the suite by adding them to
* `kunit_cases`.
*
* Often it is desirable to run some function which will set up things which
* will be used by every test; this is accomplished with an `init` function
* which runs before each test case is invoked. Similarly, an `exit` function
* may be specified which runs after every test case and can be used to for
* cleanup. For clarity, running tests in a test suite would behave as follows:
*
* suite.suite_init(suite);
* suite.init(test);
* suite.test_case[0](test);
* suite.exit(test);
* suite.init(test);
* suite.test_case[1](test);
* suite.exit(test);
* suite.suite_exit(suite);
* ...;
*/
static struct kunit_suite example_test_suite = {
.name = "example",
.init = example_test_init,
.suite_init = example_test_init_suite,
.test_cases = example_test_cases,
};
/*
* This registers the above test suite telling KUnit that this is a suite of
* tests that need to be run.
*/
kunit_test_suites(&example_test_suite);
MODULE_LICENSE("GPL v2");