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 */
 21static 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 */
 36static int example_test_init(struct kunit *test)
 37{
 38	kunit_info(test, "initializing\n");
 39
 40	return 0;
 41}
 42
 43/*
 44 * This is run once before all test cases in the suite.
 45 * See the comment on example_test_suite for more information.
 46 */
 47static int example_test_init_suite(struct kunit_suite *suite)
 48{
 49	kunit_info(suite, "initializing suite\n");
 50
 51	return 0;
 52}
 53
 54/*
 55 * This test should always be skipped.
 56 */
 57static void example_skip_test(struct kunit *test)
 58{
 59	/* This line should run */
 60	kunit_info(test, "You should not see a line below.");
 61
 62	/* Skip (and abort) the test */
 63	kunit_skip(test, "this test should be skipped");
 64
 65	/* This line should not execute */
 66	KUNIT_FAIL(test, "You should not see this line.");
 67}
 68
 69/*
 70 * This test should always be marked skipped.
 71 */
 72static void example_mark_skipped_test(struct kunit *test)
 73{
 74	/* This line should run */
 75	kunit_info(test, "You should see a line below.");
 76
 77	/* Skip (but do not abort) the test */
 78	kunit_mark_skipped(test, "this test should be skipped");
 79
 80	/* This line should run */
 81	kunit_info(test, "You should see this line.");
 82}
 83
 84/*
 85 * This test shows off all the types of KUNIT_EXPECT macros.
 86 */
 87static void example_all_expect_macros_test(struct kunit *test)
 88{
 89	const u32 array1[] = { 0x0F, 0xFF };
 90	const u32 array2[] = { 0x1F, 0xFF };
 91
 92	/* Boolean assertions */
 93	KUNIT_EXPECT_TRUE(test, true);
 94	KUNIT_EXPECT_FALSE(test, false);
 95
 96	/* Integer assertions */
 97	KUNIT_EXPECT_EQ(test, 1, 1); /* check == */
 98	KUNIT_EXPECT_GE(test, 1, 1); /* check >= */
 99	KUNIT_EXPECT_LE(test, 1, 1); /* check <= */
100	KUNIT_EXPECT_NE(test, 1, 0); /* check != */
101	KUNIT_EXPECT_GT(test, 1, 0); /* check >  */
102	KUNIT_EXPECT_LT(test, 0, 1); /* check <  */
103
104	/* Pointer assertions */
105	KUNIT_EXPECT_NOT_ERR_OR_NULL(test, test);
106	KUNIT_EXPECT_PTR_EQ(test, NULL, NULL);
107	KUNIT_EXPECT_PTR_NE(test, test, NULL);
108	KUNIT_EXPECT_NULL(test, NULL);
109	KUNIT_EXPECT_NOT_NULL(test, test);
110
111	/* String assertions */
112	KUNIT_EXPECT_STREQ(test, "hi", "hi");
113	KUNIT_EXPECT_STRNEQ(test, "hi", "bye");
114
115	/* Memory block assertions */
116	KUNIT_EXPECT_MEMEQ(test, array1, array1, sizeof(array1));
117	KUNIT_EXPECT_MEMNEQ(test, array1, array2, sizeof(array1));
118
119	/*
120	 * There are also ASSERT variants of all of the above that abort test
121	 * execution if they fail. Useful for memory allocations, etc.
122	 */
123	KUNIT_ASSERT_GT(test, sizeof(char), 0);
124
125	/*
126	 * There are also _MSG variants of all of the above that let you include
127	 * additional text on failure.
128	 */
129	KUNIT_EXPECT_GT_MSG(test, sizeof(int), 0, "Your ints are 0-bit?!");
130	KUNIT_ASSERT_GT_MSG(test, sizeof(int), 0, "Your ints are 0-bit?!");
131}
132
133/*
134 * Here we make a list of all the test cases we want to add to the test suite
135 * below.
136 */
137static struct kunit_case example_test_cases[] = {
138	/*
139	 * This is a helper to create a test case object from a test case
140	 * function; its exact function is not important to understand how to
141	 * use KUnit, just know that this is how you associate test cases with a
142	 * test suite.
143	 */
144	KUNIT_CASE(example_simple_test),
145	KUNIT_CASE(example_skip_test),
146	KUNIT_CASE(example_mark_skipped_test),
147	KUNIT_CASE(example_all_expect_macros_test),
148	{}
149};
150
151/*
152 * This defines a suite or grouping of tests.
153 *
154 * Test cases are defined as belonging to the suite by adding them to
155 * `kunit_cases`.
156 *
157 * Often it is desirable to run some function which will set up things which
158 * will be used by every test; this is accomplished with an `init` function
159 * which runs before each test case is invoked. Similarly, an `exit` function
160 * may be specified which runs after every test case and can be used to for
161 * cleanup. For clarity, running tests in a test suite would behave as follows:
162 *
163 * suite.suite_init(suite);
164 * suite.init(test);
165 * suite.test_case[0](test);
166 * suite.exit(test);
167 * suite.init(test);
168 * suite.test_case[1](test);
169 * suite.exit(test);
170 * suite.suite_exit(suite);
171 * ...;
172 */
173static struct kunit_suite example_test_suite = {
174	.name = "example",
175	.init = example_test_init,
176	.suite_init = example_test_init_suite,
177	.test_cases = example_test_cases,
178};
179
180/*
181 * This registers the above test suite telling KUnit that this is a suite of
182 * tests that need to be run.
183 */
184kunit_test_suites(&example_test_suite);
185
186MODULE_LICENSE("GPL v2");