On Mon, Feb 7, 2022 at 8:02 PM David Gow <davidgow@xxxxxxxxxx> wrote: > > list_is_head() was added recently[1], and didn't have a KUnit test. The > implementation is trivial, so it's not a particularly exciting test, but > it'd be nice to get back to full coverage of the list functions. > > [1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/include/linux/list.h?id=0425473037db40d9e322631f2d4dc6ef51f97e88 > > Signed-off-by: David Gow <davidgow@xxxxxxxxxx> Acked-by: Daniel Latypov <dlatypov@xxxxxxxxxx> One very optional suggestion below. > --- > > Changes since v1: > https://lore.kernel.org/linux-kselftest/20220205061539.273330-2-davidgow@xxxxxxxxxx/ > - Test both non-head elements of the same list and head elements of > different lists. > > --- > lib/list-test.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/lib/list-test.c b/lib/list-test.c > index 976e9ae1f3c5..1960615d1a9f 100644 > --- a/lib/list-test.c > +++ b/lib/list-test.c > @@ -252,6 +252,23 @@ static void list_test_list_bulk_move_tail(struct kunit *test) > KUNIT_EXPECT_EQ(test, i, 2); > } > > +static void list_test_list_is_head(struct kunit *test) > +{ > + struct list_head a, b, c; > + > + /* Two lists: [a] -> b, [c] */ > + INIT_LIST_HEAD(&a); > + INIT_LIST_HEAD(&c); > + list_add_tail(&b, &a); > + > + KUNIT_EXPECT_TRUE(test, list_is_head(&a, &a)); > + /* Non-head element of same list */ > + KUNIT_EXPECT_FALSE(test, list_is_head(&a, &b)); > + /* Head element of different list */ > + KUNIT_EXPECT_FALSE(test, list_is_head(&a, &c)); very optional, KUNIT_EXPECT_FALSE_MSG(test, list_is_head(&a, &c), "Head of a different list"); It goes over 80 char, so probably needs to be line-wrapped, and thus doesn't reduce # of lines. Given the simplicity of this function (checks that its args are equal), I highly doubt it should ever fail, and so better error messages aren't really much of a bonus.
