// SPDX-License-Identifier: GPL-2.0
/*
* Example KUnit test to show how to use KUnit.
*
* Copyright (C) 2019, Google LLC.
* Author: Brendan Higgins <[email protected]>
*/
#include <kunit/test.h>
#include <kunit/static_stub.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 after each test case, see the comment on
* example_test_suite for more information.
*/
static void example_test_exit(struct kunit *test)
{
kunit_info(test, "cleaning up\n");
}
/*
* 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 is run once after all test cases in the suite.
* See the comment on example_test_suite for more information.
*/
static void example_test_exit_suite(struct kunit_suite *suite)
{
kunit_info(suite, "exiting suite\n");
}
/*
* 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)
{
const u32 array1[] = { 0x0F, 0xFF };
const u32 array2[] = { 0x1F, 0xFF };
/* 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");
/* Memory block assertions */
KUNIT_EXPECT_MEMEQ(test, array1, array1, sizeof(array1));
KUNIT_EXPECT_MEMNEQ(test, array1, array2, sizeof(array1));
/*
* 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?!");
}
/* This is a function we'll replace with static stubs. */
static int add_one(int i)
{
/* This will trigger the stub if active. */
KUNIT_STATIC_STUB_REDIRECT(add_one, i);
return i + 1;
}
/* This is used as a replacement for the above function. */
static int subtract_one(int i)
{
/* We don't need to trigger the stub from the replacement. */
return i - 1;
}
/*
* If the function to be replaced is static within a module it is
* useful to export a pointer to that function instead of having
* to change the static function to a non-static exported function.
*
* This pointer simulates a module exporting a pointer to a static
* function.
*/
static int (* const add_one_fn_ptr)(int i) = add_one;
/*
* This test shows the use of static stubs.
*/
static void example_static_stub_test(struct kunit *test)
{
/* By default, function is not stubbed. */
KUNIT_EXPECT_EQ(test, add_one(1), 2);
/* Replace add_one() with subtract_one(). */
kunit_activate_static_stub(test, add_one, subtract_one);
/* add_one() is now replaced. */
KUNIT_EXPECT_EQ(test, add_one(1), 0);
/* Return add_one() to normal. */
kunit_deactivate_static_stub(test, add_one);
KUNIT_EXPECT_EQ(test, add_one(1), 2);
}
/*
* This test shows the use of static stubs when the function being
* replaced is provided as a pointer-to-function instead of the
* actual function. This is useful for providing access to static
* functions in a module by exporting a pointer to that function
* instead of having to change the static function to a non-static
* exported function.
*/
static void example_static_stub_using_fn_ptr_test(struct kunit *test)
{
/* By default, function is not stubbed. */
KUNIT_EXPECT_EQ(test, add_one(1), 2);
/* Replace add_one() with subtract_one(). */
kunit_activate_static_stub(test, add_one_fn_ptr, subtract_one);
/* add_one() is now replaced. */
KUNIT_EXPECT_EQ(test, add_one(1), 0);
/* Return add_one() to normal. */
kunit_deactivate_static_stub(test, add_one_fn_ptr);
KUNIT_EXPECT_EQ(test, add_one(1), 2);
}
static const struct example_param {
int value;
} example_params_array[] = {
{ .value = 3, },
{ .value = 2, },
{ .value = 1, },
{ .value = 0, },
};
static void example_param_get_desc(const struct example_param *p, char *desc)
{
snprintf(desc, KUNIT_PARAM_DESC_SIZE, "example value %d", p->value);
}
KUNIT_ARRAY_PARAM(example, example_params_array, example_param_get_desc);
/*
* This test shows the use of params.
*/
static void example_params_test(struct kunit *test)
{
const struct example_param *param = test->param_value;
/* By design, param pointer will not be NULL */
KUNIT_ASSERT_NOT_NULL(test, param);
/* Test can be skipped on unsupported param values */
if (!is_power_of_2(param->value))
kunit_skip(test, "unsupported param value %d", param->value);
/* You can use param values for parameterized testing */
KUNIT_EXPECT_EQ(test, param->value % param->value, 0);
}
/*
* This test shows the use of test->priv.
*/
static void example_priv_test(struct kunit *test)
{
/* unless setup in suite->init(), test->priv is NULL */
KUNIT_ASSERT_NULL(test, test->priv);
/* but can be used to pass arbitrary data to other functions */
test->priv = kunit_kzalloc(test, 1, GFP_KERNEL);
KUNIT_EXPECT_NOT_NULL(test, test->priv);
KUNIT_ASSERT_PTR_EQ(test, test->priv, kunit_get_current_test()->priv);
}
/*
* This test should always pass. Can be used to practice filtering attributes.
*/
static void example_slow_test(struct kunit *test)
{
KUNIT_EXPECT_EQ(test, 1 + 1, 2);
}
/*
* 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),
KUNIT_CASE(example_static_stub_test),
KUNIT_CASE(example_static_stub_using_fn_ptr_test),
KUNIT_CASE(example_priv_test),
KUNIT_CASE_PARAM(example_params_test, example_gen_params),
KUNIT_CASE_SLOW(example_slow_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,
.exit = example_test_exit,
.suite_init = example_test_init_suite,
.suite_exit = example_test_exit_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);
static int __init init_add(int x, int y)
{
return (x + y);
}
/*
* This test should always pass. Can be used to test init suites.
*/
static void __init example_init_test(struct kunit *test)
{
KUNIT_EXPECT_EQ(test, init_add(1, 1), 2);
}
/*
* The kunit_case struct cannot be marked as __initdata as this will be
* used in debugfs to retrieve results after test has run
*/
static struct kunit_case __refdata example_init_test_cases[] = {
KUNIT_CASE(example_init_test),
{}
};
/*
* The kunit_suite struct cannot be marked as __initdata as this will be
* used in debugfs to retrieve results after test has run
*/
static struct kunit_suite example_init_test_suite = {
.name = "example_init",
.test_cases = example_init_test_cases,
};
/*
* This registers the test suite and marks the suite as using init data
* and/or functions.
*/
kunit_test_init_section_suites(&example_init_test_suite);
MODULE_DESCRIPTION("Example KUnit test suite");
MODULE_LICENSE("GPL v2");
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