one byte change to file not detected ?

[Matt Nordhoff]

BuraphaLinux Server wrote:
> The attached script shows that on my system, mercurial cannot detect a
> 1 byte difference in a file.  Sometimes the script works, but most of
> the time it fails.  I wonder if mercurial is using the file size and
> time to skip doing a real byte-by-byte comparison, and my clock
> granularity is not fine enough?  I am willing to pay the penalty of
> the slowdown if I can force a byte-by-byte comparison of every file
> every time, but I don't know how to turn that on.
> 
> If I add a line 'sleep 1' after the first commit, then the script
> correctly works and I get 2 revisions instead of the dreaded 'nothing
> changed' message.
> 
> Is this a known issue?  Should I make a wrapper for hg that just
> always does a sleep after each operation?
> 
> I ran the tests with this:
> 
> for x in $(seq 1 10); do ./PANIC; done

Exactly. Hg doesn't do a byte-by-byte comparison if the size and
modification time haven't changed. I don't believe there's a way to
change that ATM. It would probably be easy to hack that bit out of the code.

(I didn't read the script.)
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