lib/test_sort: add a testcase to ensure code coverage

The addition of an if statement in lib/sort to handle the final unsorted 2
or 3 elements is not covered by existing test cases, leading to incomplete
test coverage.  To ensure comprehensive testing and maintain 100% code
coverage, add a new testcase for scenarios where the if statement is
triggered.

Since the if statement is only triggered when the array length is odd and
the first element is greater than the second element, a testcase is
created using an array length of TEST_LEN - 1 and a suitable random seed
to maintain full code coverage.

Link: https://lkml.kernel.org/r/20240527203011.1644280-5-visitorckw@gmail.com
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Cc: Ching-Chun (Jim) Huang <jserv@ccns.ncku.edu.tw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/lib/test_sort.c b/lib/test_sort.c
index be02e3a098cf55699b4f2a15523cd3454f639111..da44951250970b6b64e03fe174f88d4cd03ec912 100644 (file)
--- a/lib/test_sort.c
+++ b/lib/test_sort.c
@@ -29,7 +29,19 @@ static void test_sort(struct kunit *test)
 
        sort(a, TEST_LEN, sizeof(*a), cmpint, NULL);
 
-       for (i = 0; i < TEST_LEN-1; i++)
+       for (i = 0; i < TEST_LEN - 1; i++)
+               KUNIT_ASSERT_LE(test, a[i], a[i + 1]);
+
+       r = 48;
+
+       for (i = 0; i < TEST_LEN - 1; i++) {
+               r = (r * 725861) % 6599;
+               a[i] = r;
+       }
+
+       sort(a, TEST_LEN - 1, sizeof(*a), cmpint, NULL);
+
+       for (i = 0; i < TEST_LEN - 2; i++)
                KUNIT_ASSERT_LE(test, a[i], a[i + 1]);
 }