[PATCH v7 0/3] scanf: convert self-test to KUnit

Tamir Duberstein
2025-02-11T15:13:39Z

This is one of just 3 remaining "Test Module" kselftests (the others
being bitmap and printf), the rest having been converted to KUnit. In
addition to the enclosed patch, please consider this an RFC on the
removal of the "Test Module" kselftest machinery.

I tested this using:

$ tools/testing/kunit/kunit.py run --arch arm64 --make_options LLVM=1 scanf

Signed-off-by: Tamir Duberstein <tamird@gmail.com>
---
Changes in v7:
- Remove redundant debug logs. (Petr Mladek)
- Drop Petr's Acked-by.
- Use original test assertions as KUNIT_*_EQ_MSG produces hard-to-parse
messages. The new failure output is:

vsscanf("0 1e 3e43 31f0 0 0 5797 9c70", "%1hx %2hx %4hx %4hx %1hx %1hx %4hx %4hx", ...) expected 837828163 got 1044578334
not ok 1 " "
# numbers_list_field_width_val_width: ASSERTION FAILED at lib/scanf_kunit.c:92
vsscanf("dc2:1c:0:3531:2621:5172:1:7", "%3hx:%2hx:%1hx:%4hx:%4hx:%4hx:%1hx:%1hx", ...) expected 892403712 got 28
not ok 2 ":"
# numbers_list_field_width_val_width: ASSERTION FAILED at lib/scanf_kunit.c:92
vsscanf("e083,8f6e,b,70ca,1,1,aab1,10e4", "%4hx,%4hx,%1hx,%4hx,%1hx,%1hx,%4hx,%4hx", ...) expected 1892286475 got 757614
not ok 3 ","
# numbers_list_field_width_val_width: ASSERTION FAILED at lib/scanf_kunit.c:92
vsscanf("2e72-8435-1-2fc-7cbd-c2f1-7158-2b41", "%4hx-%4hx-%1hx-%3hx-%4hx-%4hx-%4hx-%4hx", ...) expected 50069505 got 99381
not ok 4 "-"
# numbers_list_field_width_val_width: ASSERTION FAILED at lib/scanf_kunit.c:92
vsscanf("403/0/17/1/11e7/1/1fe8/34ba", "%3hx/%1hx/%2hx/%1hx/%4hx/%1hx/%4hx/%4hx", ...) expected 65559 got 1507328
not ok 5 "/"
# numbers_list_field_width_val_width: pass:0 fail:5 skip:0 total:5
not ok 4 numbers_list_field_width_val_width
# numbers_slice: ASSERTION FAILED at lib/scanf_kunit.c:92
vsscanf("3c87eac0f4afa1f9231da52", "%1hx%4hx%4hx%4hx%1hx%4hx%4hx%1hx", ...) expected 1257942031 got 2886715518

- Link to v6: https://lore.kernel.org/r/20250210-scanf-kunit-convert-v6-0-4d583d07f92d@gmail.com

Changes in v6:
- s/at boot/at runtime/ for consistency with the printf series.
- Go back to kmalloc. (Geert Uytterhoeven)
- Link to v5: https://lore.kernel.org/r/20250210-scanf-kunit-convert-v5-0-8e64f3a7de99@gmail.com

Changes in v5:
- Remove extraneous trailing newlines from failure messages.
- Replace `pr_debug` with `kunit_printk`.
- Use static char arrays instead of kmalloc.
- Drop KUnit boilerplate from CONFIG_SCANF_KUNIT_TEST help text.
- Drop arch changes.
- Link to v4: https://lore.kernel.org/r/20250207-scanf-kunit-convert-v4-0-a23e2afaede8@gmail.com

Changes in v4:
- Bake `test` into various macros, greatly reducing diff noise.
- Revert control flow changes.
- Link to v3: https://lore.kernel.org/r/20250204-scanf-kunit-convert-v3-0-386d7c3ee714@gmail.com

Changes in v3:
- Reduce diff noise in lib/Makefile. (Petr Mladek)
- Split `scanf_test` into a few test cases. New output:
: =================== scanf (10 subtests) ====================
: [PASSED] numbers_simple
: ====================== numbers_list =======================
: [PASSED] delim=" "
: [PASSED] delim=":"
: [PASSED] delim=","
: [PASSED] delim="-"
: [PASSED] delim="/"
: ================== [PASSED] numbers_list ===================
: ============ numbers_list_field_width_typemax =============
: [PASSED] delim=" "
: [PASSED] delim=":"
: [PASSED] delim=","
: [PASSED] delim="-"
: [PASSED] delim="/"
: ======== [PASSED] numbers_list_field_width_typemax =========
: =========== numbers_list_field_width_val_width ============
: [PASSED] delim=" "
: [PASSED] delim=":"
: [PASSED] delim=","
: [PASSED] delim="-"
: [PASSED] delim="/"
: ======= [PASSED] numbers_list_field_width_val_width ========
: [PASSED] numbers_slice
: [PASSED] numbers_prefix_overflow
: [PASSED] test_simple_strtoull
: [PASSED] test_simple_strtoll
: [PASSED] test_simple_strtoul
: [PASSED] test_simple_strtol
: ====================== [PASSED] scanf ======================
: ============================================================
: Testing complete. Ran 22 tests: passed: 22
: Elapsed time: 5.517s total, 0.001s configuring, 5.440s building, 0.067s running
- Link to v2: https://lore.kernel.org/r/20250203-scanf-kunit-convert-v2-1-277a618d804e@gmail.com

Changes in v2:
- Rename lib/{test_scanf.c => scanf_kunit.c}. (Andy Shevchenko)
- Link to v1: https://lore.kernel.org/r/20250131-scanf-kunit-convert-v1-1-0976524f0eba@gmail.com

---
Tamir Duberstein (3):
scanf: remove redundant debug logs
scanf: convert self-test to KUnit
scanf: break kunit into test cases

MAINTAINERS | 2 +-
lib/Kconfig.debug | 12 +-
lib/Makefile | 2 +-
lib/{test_scanf.c => scanf_kunit.c} | 270 +++++++++++++++++------------------
tools/testing/selftests/lib/Makefile | 2 +-
tools/testing/selftests/lib/config | 1 -
tools/testing/selftests/lib/scanf.sh | 4 -
7 files changed, 143 insertions(+), 150 deletions(-)
---
base-commit: a64dcfb451e254085a7daee5fe51bf22959d52d3
change-id: 20250131-scanf-kunit-convert-f70dc33bb34c

Best regards,
--
Tamir Duberstein <tamird@gmail.com>