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Diffstat (limited to 'lib/kunit/kunit-example-test.c')
| -rw-r--r-- | lib/kunit/kunit-example-test.c | 377 |
1 files changed, 377 insertions, 0 deletions
diff --git a/lib/kunit/kunit-example-test.c b/lib/kunit/kunit-example-test.c new file mode 100644 index 000000000000..798924f7cc86 --- /dev/null +++ b/lib/kunit/kunit-example-test.c @@ -0,0 +1,377 @@ +// 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> +#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_LICENSE("GPL v2"); |