Re: [PATCH 02/11] t8001/t8002: blame: demonstrate -L bounds checking bug

> Eric Sunshine <sunshine@sunshineco.com> writes:
>
>> A bounds checking bug allows the X in -LX to extend one line past the
>> end of file. For example, given a file with 5 lines, -L6 is accepted as
>> valid. Demonstrate this problem.
>>
>> While here, also add tests to check that the remaining cases of X and Y
>> in -LX,Y are handled correctly at and in the vicinity of end-of-file.
>>
>> Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
>> ---
>>  t/annotate-tests.sh | 22 ++++++++++++++++++++++
>>  1 file changed, 22 insertions(+)
>>
>> diff --git a/t/annotate-tests.sh b/t/annotate-tests.sh
>> index 3524eaf..02fbbf1 100644
>> --- a/t/annotate-tests.sh
>> +++ b/t/annotate-tests.sh
>> @@ -225,10 +225,32 @@ test_expect_success 'blame -L /RE/,-N' '
>>       check_count -L/99/,-3 B 1 B2 1 D 1
>>  '
>>
>> +# 'file' ends with an incomplete line, so 'wc' reports one fewer lines than
>> +# git-blame sees, hence the last line is actually $(wc...)+1.
>> +test_expect_success 'blame -L X (X == nlines)' '
>> +     n=$(expr $(wc -l <file) + 1) &&
>> +     check_count -L$n C 1
>> +'
>> +
>> +test_expect_failure 'blame -L X (X == nlines + 1)' '
>> +     n=$(expr $(wc -l <file) + 2) &&
>> +     test_must_fail $PROG -L$n file
>> +'
>> +
>>  test_expect_success 'blame -L X (X > nlines)' '
>>       test_must_fail $PROG -L12345 file
>>  '
>> +test_expect_success 'blame -L ,Y (Y == nlines)' '
>> +     n=$(expr $(wc -l <file) + 1) &&
>> +     check_count -L,$n A 1 B 1 B1 1 B2 1 "A U Thor" 1 C 1 D 1 E 1
>> +'
>> +
>> +test_expect_success 'blame -L ,Y (Y == nlines + 1)' '
>> +     n=$(expr $(wc -l <file) + 2) &&
>> +     test_must_fail $PROG -L,$n file
>> +'
>> +
>
> This is somewhat curious.
>
> Does the problem triggers only on a file that ends with an
> incomplete line, or the test was inserted at this location only
> because it was convenient and the problem exists with or without the
> incomplete final line?
>
> I am guessing that it is the latter.