1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Example KUnit test to show how to use KUnit.
4 *
5 * Copyright (C) 2019, Google LLC.
6 * Author: Brendan Higgins <brendanhiggins@google.com>
7 */
8
9 #include <kunit/test.h>
10
11 /*
12 * This is the most fundamental element of KUnit, the test case. A test case
13 * makes a set EXPECTATIONs and ASSERTIONs about the behavior of some code; if
14 * any expectations or assertions are not met, the test fails; otherwise, the
15 * test passes.
16 *
17 * In KUnit, a test case is just a function with the signature
18 * `void (*)(struct kunit *)`. `struct kunit` is a context object that stores
19 * information about the current test.
20 */
example_simple_test(struct kunit * test)21 static void example_simple_test(struct kunit *test)
22 {
23 /*
24 * This is an EXPECTATION; it is how KUnit tests things. When you want
25 * to test a piece of code, you set some expectations about what the
26 * code should do. KUnit then runs the test and verifies that the code's
27 * behavior matched what was expected.
28 */
29 KUNIT_EXPECT_EQ(test, 1 + 1, 2);
30 }
31
32 /*
33 * This is run once before each test case, see the comment on
34 * example_test_suite for more information.
35 */
example_test_init(struct kunit * test)36 static int example_test_init(struct kunit *test)
37 {
38 kunit_info(test, "initializing\n");
39
40 return 0;
41 }
42
43 /*
44 * Here we make a list of all the test cases we want to add to the test suite
45 * below.
46 */
47 static struct kunit_case example_test_cases[] = {
48 /*
49 * This is a helper to create a test case object from a test case
50 * function; its exact function is not important to understand how to
51 * use KUnit, just know that this is how you associate test cases with a
52 * test suite.
53 */
54 KUNIT_CASE(example_simple_test),
55 {}
56 };
57
58 /*
59 * This defines a suite or grouping of tests.
60 *
61 * Test cases are defined as belonging to the suite by adding them to
62 * `kunit_cases`.
63 *
64 * Often it is desirable to run some function which will set up things which
65 * will be used by every test; this is accomplished with an `init` function
66 * which runs before each test case is invoked. Similarly, an `exit` function
67 * may be specified which runs after every test case and can be used to for
68 * cleanup. For clarity, running tests in a test suite would behave as follows:
69 *
70 * suite.init(test);
71 * suite.test_case[0](test);
72 * suite.exit(test);
73 * suite.init(test);
74 * suite.test_case[1](test);
75 * suite.exit(test);
76 * ...;
77 */
78 static struct kunit_suite example_test_suite = {
79 .name = "example",
80 .init = example_test_init,
81 .test_cases = example_test_cases,
82 };
83
84 /*
85 * This registers the above test suite telling KUnit that this is a suite of
86 * tests that need to be run.
87 */
88 kunit_test_suites(&example_test_suite);
89
90 MODULE_LICENSE("GPL v2");
91
