bug#58842: 29.0.50/tramp; copy-file KEEP-TIME gives the target earlier time

[Sam Steingold]

Hi Michael,

> * Michael Albinus <zvpunry.nyovahf@tzk.qr> [2022-10-30 16:42:21 +0100]:
>
> Sam Steingold <sds@gnu.org> writes:
>
>> One property of `copy-file' that I came to expect is:
>>
>> (copy-file src dst ...) is successful
>> ==>
>> (file-newer-than-file-p src dst) is false
>>
>> This ensures that the same file is not copied over and over.
>>
>> Alas, this does not hold in the following corner case:
>>
>> 1. src is local on mac
>> 2. dst is remote on linux
>> 3. KEEP-TIME is passed to `copy-file'
>>
>> In this case, after `(copy-file src dst t t)`,
>>
>> (file-attribute-modification-time (file-attributes dst))
>> => (25435 65247 0 0)
>> (file-attribute-modification-time (file-attributes src))
>> => (25435 65247 279367 729000)
>>
>
> Well, another fix would be to teach file-newer-than-file-p to use only
> seconds w/o fractions. Does the appended patch works for you?
>

Yes, thank you, it does appear to fix the issue.
Please note a typo in the comment in your patch.


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