Re: [Tarantool-patches] [PATCH luajit 1/2] test: introduce asserts assert_str{_not}_equal

[Sergey Bronnikov via Tarantool-patches <tarantool-patches@dev.tarantool.org>]

Hi, Igor

On 11/1/23 11:28, Igor Munkin via Tarantool-patches wrote:
> Sergey,
>
> On 01.11.23, Sergey Kaplun via Tarantool-patches wrote:
>> Hi, Sergey!
> <snipped>
>
>> If some test fails we got the following output:
>>
>> | TAP version 13
>> | 1..1
>> | not ok 1 - lua_concat_testcase
>> |   ---
>> |   location:     /home/burii/reviews/luajit/lj-881-lua-concat/test/tarantool-c-tests/lj-881-fix-lua-concat.test.c:81
>> |   failed_assertion:     assert_str_equal
>> |   got: 1652880104
>> |   expected: -1138225337
>> |   ...
>> | # Failed 1 tests out of 1
>>
>> Failed assertion field is incorrect (see the comment above).
>> But the most important is "got" and "expected" fields, that returns the
>> addresses of strings, which isn't very meaningful.
>>
>> I suggest dumping the strings instead if they are not long enough (less
>> than 128 symbols, I suppose). The maxdump string length should be
>> a customizeable parameter. I suggest defining a macro `MAX_DUMP_STRLEN`
>> inside the <test.h> header. So the user can redefine it before the
>> `assert_str_{not_}equal()` and use a custom value.
>>
>> If the string is too long, we should dump the offset of the mismatched
>> symbol. Or maybe it's better to always dump it.
>>
>> Thoughts?
> What if the different part starts after 128 symbols? I believe the most
> valuable part is the one where the difference starts, so you have to
> dump the beginning (for convenience), the difference and some numeric
> parameters (length, offset where strings differ, etc).
>
> Furthermore, I suggest implementing <*_str_*> helpers for nul-terminated
> strings and <*_mem_*> helpers for length limited memory blobs.
I would postpone implementation of  <*_mem_*> helpers until we will need 
them in tests.
>
>> Side note:
>>
>> Also, this comparing "by eye" isn't very convenient if values aren't
>> aligned, so maybe it is better to use spaces instead of tabs to align
>> values? This may be added within the separate patch series later.
> I believe, this is quite minor thing (at least for now).
>
> <snipped>
>
>> -- 
>> Best regards,
>> Sergey Kaplun