Re: [PATCH v2 1/2] t7508: add tests capturing racy timestamp handling

[Marc Strapetz <marc.strapetz@syntevo.com>]

On 05/01/2022 21:59, Junio C Hamano wrote:
>> From: Marc Strapetz <marc.strapetz@syntevo.com>
>>   
>> +test_expect_success 'racy timestamps will be fixed for clean worktree' '
>> +	echo content >racy-dirty &&
>> +	echo content >racy-racy &&
>> +	git add racy* &&
>> +	git commit -m "racy test files" &&
>> +	# let status rewrite the index, if necessary; after that we expect
>> +	# no more index writes unless caused by racy timestamps; note that
>> +	# timestamps may already be racy now (depending on previous tests)
>> +	git status &&
>> +	test-tool chmtime =1234567890 .git/index &&
>> +	test-tool chmtime --get .git/index >out &&
>> +	grep ^1234567890 out &&
> 
> If file contents were 1234567890999, this will still hit, but I do
> not think that is what you wanted to see.  Perhaps
> 
> 	git status &&
> 	echo 1234567890 >expect &&
> 	test-tool chmtime=$(cat expect) .git/index &&
> 	test-tool chmtime --get .git/index >actual &&
> 	test_cmp expect actual
> 
> or something?  But I think you inherited this bogosity from the
> previous test, so I am OK to add a few more copies of the same
> bogosity to the test.
> 
> Somebody later has to step in and clean them all up, though.  When
> that happens, we should document how the magic 1234567890 timestamp
> was chosen near its first use.

It seems like this pattern was used only once before my changes, hence I 
will extract to test-lib-functions.sh and fix the bogosity for the next 
version of my patch.

-Marc